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Sample records for nonlinear crystal yielded

  1. Nonlinear Photonic Crystal Fibers

    DEFF Research Database (Denmark)

    Hansen, Kim Per

    2004-01-01

    , leading to reduced mode confinement and dispersion flexibility. In this thesis, we treat the nonlinear photonic crystal fiber – a special sub-class of photonic crystal fibers, the core of which has a diameter comparable to the wavelength of the light guided in the fiber. The small core results in a large...... nonlinear coefficient and in various applications, it is therefore possible to reduce the required fiber lengths quite dramatically, leading to increased stability and efficiency. Furthermore, it is possible to design these fibers with zero-dispersion at previously unreachable wavelengths, paving the way...... for completely new applications, especially in and near the visible wavelength region. One such application is supercontinuum generation. Supercontinuum generation is extreme broadening of pulses in a nonlinear medium (in this case a small-core fiber), and depending on the dispersion of the fiber, it is possible...

  2. Handbook of nonlinear optical crystals

    CERN Document Server

    Dmitriev, Valentin G; Nikogosyan, David N

    1991-01-01

    This Handbook of Nonlinear Optical Crystals provides a complete description of the properties and applications of nonlinear crystals In addition, it presents the most important equations for calculating the main parameters of nonlinear frequency converters This comprehensive reference work will be of great value to all scientists and engineers working in nonlinear optics, quantum electronics and laser physics

  3. Spatial solitons in nonlinear photonic crystals

    DEFF Research Database (Denmark)

    Corney, Joel Frederick; Bang, Ole

    2000-01-01

    We study solitons in one-dimensional quadratic nonlinear photonic crystals with periodic linear and nonlinear susceptibilities. We show that such crystals support stable bright and dark solitons, even when the effective quadratic nonlinearity is zero.......We study solitons in one-dimensional quadratic nonlinear photonic crystals with periodic linear and nonlinear susceptibilities. We show that such crystals support stable bright and dark solitons, even when the effective quadratic nonlinearity is zero....

  4. Nonlinear Photonic Crystal Fibers

    DEFF Research Database (Denmark)

    Hansen, Kim Per

    2004-01-01

    Despite the general recession in the global economy and the collapse of the optical telecommunication market, research within specialty fibers is thriving. This is, more than anything else, due to the technology transition from standard all-glass fibers to photonic crystal fibers, which, instead...... of doping, use a microstructure of air and glass to obtain a refractive index difference between the core and the cladding. This air/glass microstructure lends the photonic crystal fibers a range of unique and highly usable properties, which are very different from those found in solid standard fibers....... The freedom to design the dispersion profile of the fibers is much larger and it is possible to create fibers, which support only a single spatial mode, regardless of wavelength. In comparison, the standard dispersion-shifted fibers are limited by a much lower index-contrast between the core and the cladding...

  5. Nonlinear optical crystals a complete survey

    CERN Document Server

    Nikogosyan, David N

    2005-01-01

    Nonlinear optical crystals are widely used in modern optical science and technology for frequency conversion of laser light, i.e. to generate laser radiation at any specific wavelength in visible, UV or IR spectral regions. This unrivalled reference book contains the most complete and up-to-date information on properties of nonlinear optical crystals. It includes: * Database of 63 common and novel nonlinear optical crystals * Periodically-poled and self-frequency-doubling materials * Full description of linear and nonlinear optical properties * Significant amount of crystallophysical, thermophysical, spectroscopic, electro-optic and magneto-optic information * 7 mini-reviews on novel applications, such as deep-UV light generation, terahertz-wave generation, ultrashort laser pulse compression, photonic band-gap crystals, x3 nonlinearity, etc. * More than 1500 different references with full titles It is a vital source of information for scientists and engineers dealing with modern applications of nonlinear opti...

  6. Solitons in quadratic nonlinear photonic crystals

    DEFF Research Database (Denmark)

    Corney, Joel Frederick; Bang, Ole

    2001-01-01

    We study solitons in one-dimensional quadratic nonlinear photonic crystals with modulation of both the linear and nonlinear susceptibilities. We derive averaged equations that include induced cubic nonlinearities, which can be defocusing, and we numerically find previously unknown soliton families...

  7. Functional possibilities of nonlinear crystals for frequency conversion: uniaxial crystals

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, Yu M [Institute of Monitoring of Climatic and Ecological Systems, Siberian Branch of the Russian Academy of Sciences, Tomsk (Russian Federation); Arapov, Yu D; Kasyanov, I V [E.I. Zababakhin All-Russian Scientific-Research Institute of Technical Physics, Russian Federal Nuclear Centre, Snezhinsk, Chelyabinsk region (Russian Federation); Grechin, S G; Nikolaev, P P [N.E. Bauman Moscow State Technical University, Moscow (Russian Federation)

    2016-01-31

    The method and results of the analysis of phase-matching and nonlinear properties for all point groups of symmetry of uniaxial crystals that determine their functional possibilities for solving various problems of nonlinear frequency conversion of laser radiation are presented. (nonlinear optical phenomena)

  8. The Nonlinear Analytical Envelope Equation in quadratic nonlinear crystals

    CERN Document Server

    Bache, Morten

    2016-01-01

    We here derive the so-called Nonlinear Analytical Envelope Equation (NAEE) inspired by the work of Conforti et al. [M. Conforti, A. Marini, T. X. Tran, D. Faccio, and F. Biancalana, "Interaction between optical fields and their conjugates in nonlinear media," Opt. Express 21, 31239-31252 (2013)], whose notation we follow. We present a complete model that includes $\\chi^{(2)}$ terms [M. Conforti, F. Baronio, and C. De Angelis, "Nonlinear envelope equation for broadband optical pulses in quadratic media," Phys. Rev. A 81, 053841 (2010)], $\\chi^{(3)}$ terms, and then extend the model to delayed Raman effects in the $\\chi^{(3)}$ term. We therefore get a complete model for ultrafast pulse propagation in quadratic nonlinear crystals similar to the Nonlinear Wave Equation in Frequency domain [H. Guo, X. Zeng, B. Zhou, and M. Bache, "Nonlinear wave equation in frequency domain: accurate modeling of ultrafast interaction in anisotropic nonlinear media," J. Opt. Soc. Am. B 30, 494-504 (2013)], but where the envelope is...

  9. A nonlinear viscoelastic constitutive equation - Yield predictions in multiaxial deformations

    Science.gov (United States)

    Shay, R. M., Jr.; Caruthers, J. M.

    1987-01-01

    Yield stress predictions of a nonlinear viscoelastic constitutive equation for amorphous polymer solids have been obtained and are compared with the phenomenological von Mises yield criterion. Linear viscoelasticity theory has been extended to include finite strains and a material timescale that depends on the instantaneous temperature, volume, and pressure. Results are presented for yield and the correct temperature and strain-rate dependence in a variety of multiaxial deformations. The present nonlinear viscoelastic constitutive equation can be formulated in terms of either a Cauchy or second Piola-Kirchhoff stress tensor, and in terms of either atmospheric or hydrostatic pressure.

  10. Strongly Nonlinear Transverse Perturbations in Phononic Crystals

    Directory of Open Access Journals (Sweden)

    S. Nikitenkova

    2014-01-01

    Full Text Available The dynamics of the surface heterogeneities formation in low-dimensional phononic crystals is studied. It is shown that phononic transverse perturbations in this medium are highly nonlinear. They can be described with the help of the Riemann wave and may form stable wave structures of the finite amplitude. The Riemann wave deformation is described analytically. The Riemann wave time existence up to the beginning of the gradient catastrophe is calculated.

  11. Nonlinear refractive index of optical crystals

    Science.gov (United States)

    Adair, Robert; Chase, L. L.; Payne, Stephen A.

    1989-02-01

    The nonlinear refractive indices (n2) of a large number of optical crystals have been measured at a wavelength near one micrometer with use of nearly degenerate three-wave mixing. The measurements are compared with the predictions of an empirical formula derived by Boling, Glass, and Owyoung. This formula, which relates n2 to the linear refractive index and its dispersion, is shown to be accurate to within about 30% for materials with nonlinear indices ranging over 3 orders of magnitude. Measurements for a number of binary oxide and fluoride crystals have been analyzed under the assumption that the hyperpolarizability of the anion is much larger than that of the cation. It is found that the hyperpolarizability of oxygen varies by a factor of 10, and that of fluorine varies by a factor of 7, depending on the size of the coordinating cation. This behavior is similar to that of the linear polarizability, although the hyperpolarizability is much more sensitive than the linear polarizability to the identity of the cation. The measured halide ion hyperpolarizabilities for several alkali-halide crystals are in reasonable agreement with recent self-consistent calculations. A semiempirical model was proposed by Wilson and Curtis to account for the dependence of the linear anionic polarizability on the radius of the cation. This model also accounts quite well for the variation of the hyperpolarizability of both fluorine and oxygen, except for cation partners that have filled or unfilled d-electron shells. The nonlinear indices of a number of complex oxides (i.e., those with more than one cation) have been calculated from the partial hyperpolarizabilities deduced from the data for the binary oxides. The calculated and measured values of n2 agree to within an average error of 13%.

  12. Tunable nonlinear beam defocusing in infiltrated photonic crystal fibers

    DEFF Research Database (Denmark)

    Rosberg, Christian Romer; Bennet, Francis H; Neshev, Dragomir N.;

    2007-01-01

    We demonstrate a novel experimental platform for discrete nonlinear optics based on infiltrated photonic crystal fibers. We observe tunable discrete diffraction and nonlinear self-defocusing, and apply the effects to realize a compact all-optical power limiter....

  13. Lower Bound Limit Analysis Of Slabs With Nonlinear Yield Criteria

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Damkilde, Lars

    2002-01-01

    A finite element formulation of the limit analysis of perfectly plastic slabs is given. An element with linear moment fields for which equilibrium is satisfied exactly is used in connection with an optimization algorithm taking into account the full nonlinearity of the yield criteria. Both load...

  14. Optical limiter based on two-dimensional nonlinear photonic crystals

    Science.gov (United States)

    Belabbas, Amirouche; Lazoul, Mohamed

    2016-04-01

    The aim behind this work is to investigate the capabilities of nonlinear photonic crystals to achieve ultra-fast optical limiters based on third order nonlinear effects. The purpose is to combine the actions of nonlinear effects with the properties of photonic crystals in order to activate the photonic band according to the magnitude of the nonlinear effects, themselves a function of incident laser power. We are interested in designing an optical limiter based nonlinear photonic crystal operating around 1064 nm and its second harmonic at 532 nm. Indeed, a very powerful solid-state laser that can blind or destroy optical sensors and is widely available and easy to handle. In this work, we perform design and optimization by numerical simulations to determine the better structure for the nonlinear photonic crystal to achieve compact and efficient integrated optical limiter. The approach consists to analyze the band structures in Kerr-nonlinear two-dimensional photonic crystals as a function of the optical intensity. We confirm that these bands are dynamically red-shifted with regard to the bands observed in linear photonic crystals or in the case of weak nonlinear effects. The implemented approach will help to understand such phenomena as intensitydriven optical limiting with Kerr-nonlinear photonic crystals.

  15. NONLINEARLY VIBRATIONAL ENERGY-SPECTRA OF MOLECULAR CRYSTALS

    Institute of Scientific and Technical Information of China (English)

    PANG XIAO-FENG; CHEN XIANG-RONG

    2000-01-01

    The nonlinear quantum vibrational energy spectra of amide-I in the molecular crystals acetanilide are calculatedby using the discrete nonlinear Schrodinger equation appropriate to this kind of crystals. The numerical results obtainedby this method are in good agreement with the experimental values. Meanwhile, the energy levels at high excited stateshave also been obtained for the acetanilide, which is helpful in researching the Raman scattering and infrared absorptionproperties of the this kind of crystals.

  16. Benzothiazolium Single Crystals: A New Class of Nonlinear Optical Crystals with Efficient THz Wave Generation.

    Science.gov (United States)

    Lee, Seung-Heon; Lu, Jian; Lee, Seung-Jun; Han, Jae-Hyun; Jeong, Chan-Uk; Lee, Seung-Chul; Li, Xian; Jazbinšek, Mojca; Yoon, Woojin; Yun, Hoseop; Kang, Bong Joo; Rotermund, Fabian; Nelson, Keith A; Kwon, O-Pil

    2017-08-01

    Highly efficient nonlinear optical organic crystals are very attractive for various photonic applications including terahertz (THz) wave generation. Up to now, only two classes of ionic crystals based on either pyridinium or quinolinium with extremely large macroscopic optical nonlinearity have been developed. This study reports on a new class of organic nonlinear optical crystals introducing electron-accepting benzothiazolium, which exhibit higher electron-withdrawing strength than pyridinium and quinolinium in benchmark crystals. The benzothiazolium crystals consisting of new acentric core HMB (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium) exhibit extremely large macroscopic optical nonlinearity with optimal molecular ordering for maximizing the diagonal second-order nonlinearity. HMB-based single crystals prepared by simple cleaving method satisfy all required crystal characteristics for intense THz wave generation such as large crystal size with parallel surfaces, moderate thickness and high optical quality with large optical transparency range (580-1620 nm). Optical rectification of 35 fs pulses at the technologically very important wavelength of 800 nm in 0.26 mm thick HMB crystal leads to one order of magnitude higher THz wave generation efficiency with remarkably broader bandwidth compared to standard inorganic 0.5 mm thick ZnTe crystal. Therefore, newly developed HMB crystals introducing benzothiazolium with extremely large macroscopic optical nonlinearity are very promising materials for intense broadband THz wave generation and other nonlinear optical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Nonlinear spin wave coupling in adjacent magnonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sadovnikov, A. V., E-mail: sadovnikovav@gmail.com; Nikitov, S. A. [Laboratory “Metamaterials,” Saratov State University, Saratov 410012 (Russian Federation); Kotel' nikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, Moscow 125009 (Russian Federation); Beginin, E. N.; Morozova, M. A.; Sharaevskii, Yu. P.; Grishin, S. V.; Sheshukova, S. E. [Laboratory “Metamaterials,” Saratov State University, Saratov 410012 (Russian Federation)

    2016-07-25

    We have experimentally studied the coupling of spin waves in the adjacent magnonic crystals. Space- and time-resolved Brillouin light-scattering spectroscopy is used to demonstrate the frequency and intensity dependent spin-wave energy exchange between the side-coupled magnonic crystals. The experiments and the numerical simulation of spin wave propagation in the coupled periodic structures show that the nonlinear phase shift of spin wave in the adjacent magnonic crystals leads to the nonlinear switching regime at the frequencies near the forbidden magnonic gap. The proposed side-coupled magnonic crystals represent a significant advance towards the all-magnonic signal processing in the integrated magnonic circuits.

  18. Nonlinear material behaviour of spider silk yields robust webs.

    Science.gov (United States)

    Cranford, Steven W; Tarakanova, Anna; Pugno, Nicola M; Buehler, Markus J

    2012-02-01

    Natural materials are renowned for exquisite designs that optimize function, as illustrated by the elasticity of blood vessels, the toughness of bone and the protection offered by nacre. Particularly intriguing are spider silks, with studies having explored properties ranging from their protein sequence to the geometry of a web. This material system, highly adapted to meet a spider's many needs, has superior mechanical properties. In spite of much research into the molecular design underpinning the outstanding performance of silk fibres, and into the mechanical characteristics of web-like structures, it remains unknown how the mechanical characteristics of spider silk contribute to the integrity and performance of a spider web. Here we report web deformation experiments and simulations that identify the nonlinear response of silk threads to stress--involving softening at a yield point and substantial stiffening at large strain until failure--as being crucial to localize load-induced deformation and resulting in mechanically robust spider webs. Control simulations confirmed that a nonlinear stress response results in superior resistance to structural defects in the web compared to linear elastic or elastic-plastic (softening) material behaviour. We also show that under distributed loads, such as those exerted by wind, the stiff behaviour of silk under small deformation, before the yield point, is essential in maintaining the web's structural integrity. The superior performance of silk in webs is therefore not due merely to its exceptional ultimate strength and strain, but arises from the nonlinear response of silk threads to strain and their geometrical arrangement in a web.

  19. Spectral characteristics and nonlinear studies of crystal violet dye

    Science.gov (United States)

    Sukumaran, V. Sindhu; Ramalingam, A.

    2006-03-01

    Solid-state dye-doped polymer is an attractive alternative to the conventional liquid dye solution. In this paper, the spectral characteristics and the nonlinear optical properties of the dye crystal violet are studied. The spectral characteristics of crystal violet dye doped poly(methylmethacrylate) modified with additive n-butyl acetate (nBA) are studied by recording its absorption and fluorescence spectra and the results are compared with the corresponding liquid mixture. The nonlinear refractive index of the dye in nBA and dye doped polymer film were measured using z-scan technique, by exciting with He-Ne laser. The results obtained are intercompared. Both the samples of dye crystal violet show a negative nonlinear refractive index. The origin of optical nonlinearity in the dye may be attributed due to laser-heating induced nonlinear effect.

  20. Simulation of Nonlinear Gain Saturation in Active Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2012-01-01

    In this paper we present a theoretical analysis of slowlight enhanced traveling wave amplification in an active semiconductor Photonic crystal waveguides. The impact of group index on nonlinear modal gain saturation is investigated.......In this paper we present a theoretical analysis of slowlight enhanced traveling wave amplification in an active semiconductor Photonic crystal waveguides. The impact of group index on nonlinear modal gain saturation is investigated....

  1. Nonlinear Gain Saturation in Active Slow Light Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2013-01-01

    We present a quantitative three-dimensional analysis of slow-light enhanced traveling wave amplification in an active semiconductor photonic crystal waveguides. The impact of slow-light propagation on the nonlinear gain saturation of the device is investigated.......We present a quantitative three-dimensional analysis of slow-light enhanced traveling wave amplification in an active semiconductor photonic crystal waveguides. The impact of slow-light propagation on the nonlinear gain saturation of the device is investigated....

  2. Reformulation of Nonlinear Anisotropic Crystal Elastoplasticity for Impact Physics

    Science.gov (United States)

    2015-03-01

    JD. Modeling nonlinear electromechanical behavior of shocked silicon carbide. Journal of Applied Physics . 2010;107:013520. 30. Clayton JD. A... Physics by JD Clayton Approved for public release; distribution unlimited. NOTICES Disclaimers...of Nonlinear Anisotropic Crystal Elastoplasticity for Impact Physics by JD Clayton Weapons and Materials Research Directorate, ARL

  3. Theoretical and Numerical Study of Nonlinear Phononic Crystals

    Science.gov (United States)

    Guerder, Pierre-Yves

    This work is dedicated to the theoretical and numerical study of nonlinear phononic crystals. The studied nonlinearities are those due to the second (quadratic) and third (cubic) order elastic constants of the materials that constitute the crystals. Nonlinear effects are studied by the means of finite element methods, used to simulate the propagation of an elastic wave through the crystals. A first research project concerns the study of a bone structure, namely the dispersion of elastic waves in a structure composed of collagen and hydroxy apatite alternate constituent layers. Simulations showed that it exists a strong link between bones hydration and their ability to dissipate the energy. The second study relates to an elastic resonator. A structure composed of steel inclusions in a silica matrix shows a switch behavior when the cubic nonlinearities of steel are taken into account. This strong nonlinear effect appears when the amplitude of the incident wave reaches a threshold. A full analytical model is provided. The last study demonstrates the design of composite materials with both strong cubic nonlinearities and weak quadratic nonlinearities. The derivation of the mixing laws of the elastic parameters of a nonlinear material inside a linear one is performed up to order three. Equations show a strong amplification of the nonlinear parameters of the material for some concentrations. Numerical simulations allow to conclude that the above mentioned resonator can be produced.

  4. The Kerr nonlinearity of the beta-barium borate crystal

    DEFF Research Database (Denmark)

    Bache, Morten; Guo, Hairun; Zhou, Binbin

    2013-01-01

    A popular crystal for ultrafast cascading experiments is beta-barium-borate (β-BaB2O4, BBO). It has a decent quadratic nonlinear coefficient, and because the crystal is anisotropie it can be birefringence phase-matched for type I (oo → e) second-harmonic generation (SHG). For femtosecond...

  5. Extra phase noise from thermal fluctuations in nonlinear optical crystals

    DEFF Research Database (Denmark)

    César, J. E. S.; Coelho, A.S.; Cassemiro, K.N.

    2009-01-01

    We show theoretically and experimentally that scattered light by thermal phonons inside a second-order nonlinear crystal is the source of additional phase noise observed in optical parametric oscillators. This additional phase noise reduces the quantum correlations and has hitherto hindered the d...... the direct production of multipartite entanglement in a single nonlinear optical system. We cooled the nonlinear crystal and observed a reduction in the extra noise. Our treatment of this noise can be successfully applied to different systems in the literature....

  6. High-Dimensional Nonlinear Envelope Equations and Nonlinear Localized Excitations in Photonic Crystals

    Institute of Scientific and Technical Information of China (English)

    HANG Chao; HUANG Guo-Xiang

    2006-01-01

    We investigate the nonlinear localized structures of optical pulses propagating in a one-dimensional photonic crystal with a quadratic nonlinearity. Using a method of multiple scales we show that the nonlinear evolution of a wave packet, formed by the superposition of short-wavelength excitations, and long-wavelength mean fields, generated by the self-interaction of the wave packet, are governed by a set of coupled high-dimensional nonlinear envelope equations, which can be reduced to Davey-Stewartson equations and thus support dromionlike high-dimensional nonlinear excitations in the system.

  7. Nonlinear Optical BBO Crystals: Growth, Properties and Applications

    Institute of Scientific and Technical Information of China (English)

    唐鼎元

    2000-01-01

    Low temperature phase barium metaborate β-BaB2O4 (BBO) is an important nonlinear optical material. Up to now, the BBO single crystals with large size and good optical quality were grown from Na2O or NaF fluxed solvents by the top-seeded solution growth (TSSG) technique with or without pulling. In order to improve the growth rate and quality of BBO crystals, several new techniques such as continuous feeding, forced stirring and cooling growing crystals etc. have been suggested. Applications of BBO as an excellent nonlinear optical crystal include mainly frequency conversion of various laser radiation, high average power frequency conversion, frequency doubling of ultrashort pulses and broadly tunable optical parametric oscillators (OPO).This paper is a brief review on the growth, properties and applications of BBO crystals.

  8. Nonlinear femtosecond pulse compression in cholesteric liquid crystals (Conference Presentation)

    Science.gov (United States)

    Liu, Yikun; Zhou, Jianying; Lin, Tsung-Hsien; Khoo, Iam-Choon

    2016-09-01

    Liquid crystals materials have the advantage of having a large nonlinear coefficient, but the response time is slow, normally up to several minisecond. This makes it is hard to apply in ultra fast optical devices. Recently, fentosecond (fs) nonlinear effect in choleteric liquid crystals is reported, nonlinear coefficient in the scale of 10-12 cm2/W is achieved. Base on this effect, in this work, fentosecond pulse compression technique in a miniature choleteric liquid crystal is demonstrated1,2. Cholesteric liquid crystals (CLC) is a kind of 1-dimensional phontonic structure with helical periodic. In a 10 μm thick CLC, femtosecond pulse with 100 fs is compressed to about 50 fs. CLC sample in planar texture with 500μm thick cell gap is further fabricated. In this sample, femtosecond pulse with 847 fs can be compressed to 286 fs. Due to the strong dispersion at the edge of photonic band gap, femtosecond pulse stretching and compensation can be achieve. In this experiment, laser pulse with duration 90 fs is stretched to above 2 picosecond in the first CLC sample and re-compressed to 120 fs in the second sample. Such technique might be applied in chirp pulse amplification. In conclusion, we report ultra fast nonlinear effect in cholesteric liquid crystals. Due to the strong dispersion and nonlinearity of CLC, femtosecond pulse manipulating devices can be achieved in the scale of micrometer.

  9. NonLinear Effects in Photorefractive Crystals

    Science.gov (United States)

    1988-01-01

    Counterpropagating beams impinging on a crystal exhibiting optical activity was studied by Kukhtarev, Dov- galenko and Starkov [741. Diffraction...Dovgalenko, and V. N. Starkov . Influence of the optical activity on hologram formation in photorefractive crystals. Applied Physics A, 33:227-230, 1984

  10. Equilateral pentagon polarization maintaining photonic crystal fibre with low nonlinearity

    Institute of Scientific and Technical Information of China (English)

    Yang Han-Rui; Li Xu-You; Hong Wei; Hao Jin-Hui

    2012-01-01

    A new pentagon polarization maintaining photonic crystal fibre with low nonlinearity is introduced. The full vector finite element method was used to investigate the distribution and the effective area of modal field,the nonlinear properties,the effective indices of two orthogonal polarization modes and the birefringence of the new PM-PCF effectively.It is found that the birefringence of the new polarization maintaining photonic crystal fibre can easily achieve the order of 10-4,and it can obtain higher birefringence,larger effectively mode-field area and lower nonlinearity than traditional hexagonal polarization maintaining photonic crystal fibre with the same hole pitch,same hole diameter,and same ring number.It is important for sensing and communication applications,especially has potential application for fibre optical gyroscope.

  11. Molecular and crystal design of nonlinear optical organic materials

    Energy Technology Data Exchange (ETDEWEB)

    Suponitsky, Kirill Yu; Antipin, Mikhail Yu [A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow (Russian Federation); Timofeeva, Tatiana V [Department of Chemistry, New Mexico Highlands University (United States)

    2006-06-30

    The results of theoretical and experimental studies on the second-order molecular and crystal nonlinear optical susceptibilities of organic and several classes of organoelement compounds are summarised. Modern methods used in these studies are briefly characterised, their advantages and drawbacks are outlined as regards their application to the systematic search for efficient nonlinear optical materials. Recent achievements and the main challenges in the field are thoroughly discussed and an optimum algorithm of the design of such materials is proposed.

  12. Nonlinear Phononic Periodic Structures and Granular Crystals

    Science.gov (United States)

    2012-02-10

    of the advanced delay equation (13) and they compared the numerically obtained solutions with those of approximated PDEs. Recently, Starosvetsky... KdV ), a nonlinear partial differential equation , and have been discovered in myriad systems and discrete nonlinear lattices of all the above types...granular chain, and derived the following KdV equation : t 0 0 1/2 2 2 2 2 0 0 0 0 0 0, 2 6 , , . 6 xx x xc uc A R c R c Rc m σξ ξ γξ ξξ ξ δ γ σ δ

  13. Nonlinear switching dynamics in a photonic-crystal nanocavity

    DEFF Research Database (Denmark)

    Yu, Yi; Palushani, Evarist; Heuck, Mikkel;

    2014-01-01

    the cavity is perturbed by strong pulses, we observe several nonlinear effects, i.e., saturation of the switching contrast, broadening of the switching window, and even initial reduction of the transmission. The effects are analyzed by comparison with nonlinear coupled mode theory and explained in terms......We report the experimental observation of nonlinear switching dynamics in an InP photonic crystal nanocavity. Usually, the regime of relatively small cavity perturbations is explored, where the signal transmitted through the cavity follows the temporal variation of the cavity resonance. When...... of large dynamical variations of the cavity resonance in combination with nonlinear losses. The results provide insight into the nonlinear optical processes that govern the dynamics of nanocavities and are important for applications in optical signal processing, where one wants to optimize the switching...

  14. Birefringent Bragg Gratings in Highly-Nonlinear Photonic Crystal Fiber

    Institute of Scientific and Technical Information of China (English)

    Kevin Cook; John Canning; John Holdsworth

    2008-01-01

    Efficient writing of Bragg gratings in 12-ring highly-nonlinear photonic crystal fibers is described. Experimental and numerical investigations are performed to reveal the optimum angle for coupling UV writing light to the core. Furthermore, we show that the formation of a strongly briefringent grating is at a particular angle of orientation.

  15. Nonlinear refractive index measurements of glasses and crystals

    Science.gov (United States)

    Adair, R.; Chase, L. L.; Payne, S. A.

    1987-12-01

    We have measured the nonlinear index for numerous glasses and crystals with the goal of determining the material properties that contribute to the magnitude and dispersion of n sub 2. We have found that a nearly-degenerate three-wave-mixing (TWM) process is the most useful method since it can provide both rapid and accurate n sub 2 measurements.

  16. Kyropoulos method for growth of nonlinear optical organic crystal ABP (4-aminobenzophenone) from the melt

    Science.gov (United States)

    Pan, Shoukui; Okano, Y.; Tsunekawa, S.; Fukuda, T.

    1993-03-01

    The Kyropoulus method was used to grow nonlinear optical organic crystals ABP (4-aminobenzophenone). The crystals were characterized by nonlinear optical measurements and had a large effect of frequency doubling.

  17. A novel organic nonlinear optical crystal: Creatininium succinate

    Energy Technology Data Exchange (ETDEWEB)

    Thirumurugan, R.; Anitha, K., E-mail: singlecerystalxrd@gmail.ciom [School of Physics, Madurai Kamraj University, Madurai 625021 (India)

    2015-06-24

    A novel organic material complex of creatininium succinate (CS) has been synthesized and single crystals were grown by the reaction of creatinine and succinic acid from aqueous solution by employing the technique of slow evaporation at room temperature. The structure of the grown crystal has been elucidated using single crystal X-ray diffraction analysis and the structure was refined by least-squares method to R = 0.027 for 1840 reflections. FT-IR spectral investigation has been carried out to identify the various functional groups in the title compound. UV–Vis transmission was carried out which shows the crystal has a good optical transmittance in the visible region with lower cutoff wavelength around 220 nm. Nonlinear optical property of the crystal was confirmed by Kurtz-Perry powder technique.

  18. Crystal growth in fluid flow: Nonlinear response effects

    Science.gov (United States)

    Peng, H. L.; Herlach, D. M.; Voigtmann, Th.

    2017-08-01

    We investigate crystal-growth kinetics in the presence of strong shear flow in the liquid, using molecular-dynamics simulations of a binary-alloy model. Close to the equilibrium melting point, shear flow always suppresses the growth of the crystal-liquid interface. For lower temperatures, we find that the growth velocity of the crystal depends nonmonotonically on the shear rate. Slow enough flow enhances the crystal growth, due to an increased particle mobility in the liquid. Stronger flow causes a growth regime that is nearly temperature-independent, in striking contrast to what one expects from the thermodynamic and equilibrium kinetic properties of the system, which both depend strongly on temperature. We rationalize these effects of flow on crystal growth as resulting from the nonlinear response of the fluid to strong shearing forces.

  19. Nonlinear optical response of a two-dimensional atomic crystal.

    Science.gov (United States)

    Merano, Michele

    2016-01-01

    The theory of Bloembergen and Pershan for the light waves at the boundary of nonlinear media is extended to a nonlinear two-dimensional (2D) atomic crystal, i.e., a single planar atomic lattice, placed between linear bulk media. The crystal is treated as a zero-thickness interface, a real 2D system. Harmonic waves emanate from it. Generalization of the laws of reflection and refraction give the direction and the intensity of the harmonic waves. As a particular case that contains all the essential physical features, second-order harmonic generation is considered. The theory, due to its simplicity that stems from the special character of a single planar atomic lattice, is able to elucidate and explain the rich experimental details of harmonic generation from a 2D atomic crystal.

  20. Nonlinear light propagation in chalcogenide photonic crystal slow light waveguides.

    Science.gov (United States)

    Suzuki, Keijiro; Baba, Toshihiko

    2010-12-06

    Optical nonlinearity can be enhanced by the combination of highly nonlinear chalcogenide glass and photonic crystal waveguides (PCWs) providing strong optical confinement and slow-light effects. In a Ag-As(2)Se(3) chalcogenide PCW, the effective nonlinear parameter γeff reaches 6.3 × 10(4) W(-1)m(-1), which is 200 times larger than that in Si photonic wire waveguides. In this paper, we report the detailed design, fabrication process, and the linear and nonlinear characteristics of this waveguide at silica fiber communication wavelengths. We show that the waveguide exhibits negligible two-photon absorption, and also high-efficiency self-phase modulation and four-wave mixing, which are assisted by low-dispersion slow light.

  1. Nonlinear microwave switching response of BSCCO single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, T.; Sridhar, S. [Northeastern Univ., Boston, MA (United States). Dept. of Physics; Willemsen, B.A. [Northeastern Univ., Boston, MA (United States). Dept. of Physics]|[Rome Lab., Hanscom AFB, MA (United States); Li, Qiang [Brookhaven National Lab., Upton, NY (United States); Gu, G.D.; Koshizuka, N. [Superconductivity Research Lab., Tokyo (Japan)

    1996-06-01

    Measurements of the surface impedance in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} single crystal with microwave currents flowing along the {cflx c} axis show clear evidence of a step-like nonlinearity. The surface resistance switches between apparently quantized levels for microwave field strength changes < 1 mG. This nonlinear response can arise from the presence of intrinsic Josephson junctions along the {cflx c} axis of these samples driven by the microwave current.

  2. Investigation on nonlinear optical and dielectric properties of L-arginine doped ZTC crystal to explore photonic device applications

    Directory of Open Access Journals (Sweden)

    Anis Mohd

    2016-09-01

    Full Text Available The present study is focused to explore the photonic device applications of L-arginine doped ZTC (LA-ZTC crystals using nonlinear optical (NLO and dielectric studies. The LA-ZTC crystals have been grown by slow evaporation solution technique. The chemical composition and surface of LA-ZTC crystal have been analyzed by means of energy dispersive spectroscopy (EDS and surface scanning electron microscopy (SEM techniques. The Vicker’s microhardness study has been carried out to determine the hardness, work hardening index, yield strength and elastic stiffness of LA-ZTC crystal. The enhanced SHG efficiency of LA-ZTC crystal has been ascertained using the Kurtz-Perry powder SHG test. The closed-and-open aperture Z-scan technique has been employed to confirm the third order nonlinear optical nature of LA-ZTC crystal. The Z-scan transmittance data has been utilized to calculate the superior cubic susceptibility, nonlinear refractive index, nonlinear absorption coefficient and figure of merit of LA-ZTC crystal. The behavior of dielectric constant and dielectric loss of LA-ZTC crystal at different temperatures has been investigated using the dielectric analysis.

  3. Non-linear optical titanyl arsenates: Crystal growth and properties

    Science.gov (United States)

    Nordborg, Jenni Eva Louise

    Crystals are appreciated not only for their appearance, but also for their unique physical properties which are utilized by the photonic industry in appliances that we come across every day. An important part of enabling the technical use of optical devices is the manufacture of crystals. This dissertation deals with a specific group of materials called the potassium titanyl phosphate (KIP) family, known for their non-linear optical and ferroelectric properties. The isomorphs vary in their linear optical and dielectric properties, which can be tuned to optimize device performance by forming solid solutions of the different materials. Titanyl arsenates have a wide range of near-infrared transmission which makes them useful for tunable infrared lasers. The isomorphs examined in the present work were primarily RbTiOASO4 (RTA) and CsTiOAsO4 (CTA) together with the mixtures RbxCs 1-xTiOAsO4 (RCTA). Large-scale crystals were grown by top seeding solution growth utilizing a three-zone furnace with excellent temperature control. Sufficiently slow cooling and constant upward lifting produced crystals with large volumes useable for technical applications. Optical quality RTA crystals up to 10 x 12 x 20 mm were grown. The greater difficulty in obtaining good crystals of CTA led to the use of mixed RCTA materials. The mixing of rubidium and cesium in RCTA is more favorable to crystal growth than the single components in pure RTA and CTA. Mixed crystals are rubidium-enriched and contain only 20-30% of the cesium concentration in the flux. The cesium atoms show a preference for the larger cation site. The network structure is very little affected by the cation substitution; consequently, the non-linear optical properties of the Rb-rich isomorphic mixtures of RTA and CTA can be expected to remain intact. Crystallographic methods utilizing conventional X-ray tubes, synchrotron radiation and neutron diffraction have been employed to investigate the properties of the atomic

  4. Growth and properties of semi-organic nonlinear optical crystal: L-Glutamic acid hydrochloride

    Directory of Open Access Journals (Sweden)

    J. Uma

    2016-02-01

    Full Text Available Semiorganic nonlinear optical crystal of L-Glutamic acid hydrochloride (LGHC was grown from aqueous solution by slow evaporation technique. Single crystal X-ray Diffraction analysis confirms that LGHC crystallizes in orthorhombic system with noncentrosymmetric space group P212121. The powder X-ray diffraction study confirms the crystallinity of the grown crystal. The fundamental functional groups of the grown crystals were analyzed by Fourier Transform Infrared spectroscopic analysis in the range of 450–4000 cm−1. The range of optical transmission was ascertained using UV–vis–NIR studies. The Refractive Index of the LGHC crystal was found to be 1.4. The second harmonic generation efficiency of the LGHC was determined using Kurtz and Perry powder technique and it was 0.5 times greater than that of the KDP crystal. Thermo Gravimetric Analysis (TGA and Differential Thermal Analysis (DTA were used to study thermal behavior of the sample. The dielectric behavior and ac conductivity of the sample were studied as a function of frequency for different temperatures. The mechanical strength of the crystal was determined by Vicker׳s Hardness test. The elastic stiffness constant and yield strength of the sample was calculated.

  5. Crystal growth of an organic non-linear optical material from the vapour phase

    CERN Document Server

    Hou, W

    1999-01-01

    Due to the potential applications of organic non-linear optical materials in the areas of optical processing and communication, the investigation of the crystal growth of new organic NLO materials has been an active field for the last 20 years. For such uses it is necessary to produce single crystals of high quality and perfection, free of strain and defects. When crystals are grown from the solution and the melt, solvent and the decomposition component in the melt can introduce impurities and imperfection to the as-grown crystals. For crystals grown from vapour phase, in the absence of the solvent, this cannot occur and the method promises to yield single crystals of higher quality. Despite this attraction, little attention has been paid to the vapour phase growth of organic NLO crystals. It was with this in mind that the following investigation was carried out. Using Methyl p-hydroxybenzoate (p-MHB), a potential organic NLO material, a comparison investigation was made of its crystal growth from both the va...

  6. Photonic Crystal Nanocavity Devices for Nonlinear Signal Processing

    DEFF Research Database (Denmark)

    Yu, Yi

    , membranization of InP/InGaAs structure and wet etching. Experimental investigation of the switching dynamics of InP photonic crystal nanocavity structures are carried out using short-pulse homodyne pump-probe techniques, both in the linear and nonlinear region where the cavity is perturbed by a relatively small......This thesis deals with the investigation of InP material based photonic crystal cavity membrane structures, both experimentally and theoretically. The work emphasizes on the understanding of the physics underlying the structures’ nonlinear properties and their applications for all-optical signal...... and large pump power. The experimental results are compared with coupled mode equations developed based on the first order perturbation theory, and carrier rate equations we established for the dynamics of the carrier density governing the cavity properties. The experimental observations show a good...

  7. GaInP on oxide nonlinear photonic crystal technology.

    Science.gov (United States)

    Martin, Aude; Sanchez, Dorian; Combrié, Sylvain; de Rossi, Alfredo; Raineri, Fabrice

    2017-02-01

    Heat dissipation is improved in nonlinear III-V photonic crystal waveguides owing to the hybrid III-V/Silicon integration platform, allowing efficient four-wave mixing in the continuous-wave regime. A conversion efficiency of -17.6  dB is demonstrated with a pump power level below 100 mW in a dispersion-engineered waveguide with a flat group index of 28 over a 10 nm bandwidth.

  8. Crystallization of inorganic nonlinear optical zinc di-magnesium chloro sulphate (ZDMCS) single crystal

    Science.gov (United States)

    Arivuselvi, R.; Ruban Kumar, A.

    2017-02-01

    The growth of inorganic zinc di-magnesium chloro sulphate (ZDMCS) nonlinear optical material from low temperature evaporation technique at ambient temperature has been reported. The dimension of harvested crystal is 28×10×2 mm3 and is possess rectangular shape morphology. The single crystal X-ray diffraction studies confirmed that the grown crystal belongs to the system of trigonal. The S-Cl stretching vibrations and Mg2+ ions present in the sample were observed by FTIR spectrometer. The cut-off wavelength of the grown crystal is about 203 nm is found by UV-visible absorption spectrum. The nonlinear optical efficiency was determined by powder Kurtz Perry technique. EDAX spectrum confirms the presence of elements within the material. Dielectric nature of the sample was analyzed for the frequency range 50 Hz to 5 MHz at different temperatures. The mechanical behaviour of the title compound was investigated using Vicker's microhardness tester.

  9. Temporal nonlinear beam dynamics in infiltrated photonic crystal fibers

    DEFF Research Database (Denmark)

    Bennet, Francis; Rosberg, Christian Romer; Neshev, Dragomir N.

    of nonlinear beam reshaping occurring on a short time scale before the establishment of a steady state regime. In experiment, a 532nm laser beam can be injected into a single hole of an infiltrated PCF cladding structure, and the temporal dynamics of the nonlinear response is measured by monitoring......Liquid-infiltrated photonic crystal fibers (PCFs) offer a new way of studying light propagation in periodic and discrete systems. A wide range of available fiber structures combined with the ease of infiltration opens up a range of novel experimental opportunities for optical detection and bio......-sensing as well as active devices for all-optical switching at low (mW) laser powers. Commercially available PCFs infiltrated with liquids also provide a versatile and compact tool for exploration of the fundamentals of nonlinear beam propagation in periodic photonic structures. To explore the full scientific...

  10. Nonlinear MIMO Control of a Continuous Cooling Crystallizer

    Directory of Open Access Journals (Sweden)

    Pedro Alberto Quintana-Hernández

    2012-01-01

    Full Text Available In this work, a feedback control algorithm was developed based on geometric control theory. A nonisothermal seeded continuous crystallizer model was used to test the algorithm. The control objectives were the stabilization of the third moment of the crystal size distribution (μ3 and the crystallizer temperature (T; the manipulated variables were the stirring rate and the coolant flow rate. The nonlinear control (NLC was tested at operating conditions established within the metastable zone. Step changes of magnitudes ±0.0015 and ±0.5°C were introduced into the set point values of the third moment and crystallizer temperature, respectively. In addition, a step change of ±1°C was introduced as a disturbance in the feeding temperature. Closed-loop stability was analyzed by calculating the eigenvalues of the internal dynamics. The system presented a stable dynamic behavior when the operation conditions maintain the crystallizer concentration within the metastable zone. Closed-loop simulations with the NLC were compared with simulations that used a classic PID controller. The PID controllers were tuned by minimizing the integral of the absolute value of the error (IAE criterion. The results showed that the NLC provided a suitable option for continuous crystallization control. For all analyzed cases, the IAEs obtained with NLC were smaller than those obtained with the PID controller.

  11. Optical Solitons in a Trinal-channel Inverted Nonlinear Photonic Crystal

    CERN Document Server

    Chen, Guihua; Wu, Muying

    2014-01-01

    Inverted nonlinear photonic crystals are the crystals featuring competition between linear and nonlinear lattices, with minima of the linear potential coinciding with maxima of the nonlinear pseudopotential, and vice versa. Traditional inverted nonlinear photonic crystals only have two channels, and can be attained experimentally by means of Rhodamine B (RhB, a dye featuring saturable absorption) doped into the SU-8 polymer. In this paper, a new type of inverted nonlinear photonic crystal is constructed by juxtaposing three kinds of channels into a period. These three channels are a purely linear channel, a saturable self-focusing nonlinear channel, and a saturable self-defocusing nonlinear channel. This optical device is assumed to be fabricated by means of SU-8 polymer material periodically doped with two types of active dyes. The nonlinear propagation of a light field inside this device (passing along the channel) can be described by a nonlinear Schrodinger equation. Stable multi-peak fundamental and dipol...

  12. Modeling of dispersion and nonlinear characteristics of tapered photonic crystal fibers for applications in nonlinear optics

    Science.gov (United States)

    Pakarzadeh, H.; Rezaei, S. M.

    2016-01-01

    In this article, we investigate for the first time the dispersion and the nonlinear characteristics of the tapered photonic crystal fibers (PCFs) as a function of length z, via solving the eigenvalue equation of the guided mode using the finite-difference frequency-domain method. Since the structural parameters such as the air-hole diameter and the pitch of the microstructured cladding change along the tapered PCFs, dispersion and nonlinear properties change with the length as well. Therefore, it is important to know the exact behavior of such fiber parameters along z which is necessary for nonlinear optics applications. We simulate the z dependency of the zero-dispersion wavelength, dispersion slope, effective mode area, nonlinear parameter, and the confinement loss along the tapered PCFs and propose useful relations for describing dispersion and nonlinear parameters. The results of this article, which are in a very good agreement with the available experimental data, are important for simulating pulse propagation as well as investigating nonlinear effects such as supercontinuum generation and parametric amplification in tapered PCFs.

  13. Multistable internal resonance in electroelastic crystals with nonlinearly coupled modes

    Science.gov (United States)

    Kirkendall, Christopher R.; Kwon, Jae W.

    2016-03-01

    Nonlinear modal interactions have recently become the focus of intense research in micro- and nanoscale resonators for their use to improve oscillator performance and probe the frontiers of fundamental physics. However, our understanding of modal coupling is largely restricted to clamped-clamped beams, and lacking in systems with both geometric and material nonlinearities. Here we report multistable energy transfer between internally resonant modes of an electroelastic crystal plate and use a mixed analytical-numerical approach to provide new insight into these complex interactions. Our results reveal a rich bifurcation structure marked by nested regions of multistability. Even the simple case of two coupled modes generates a host of topologically distinct dynamics over the parameter space, ranging from the usual Duffing bistability to complex multistable behaviour and quasiperiodic motion.

  14. Highly Nonlinear and Birefringent Spiral Photonic Crystal Fiber

    Directory of Open Access Journals (Sweden)

    S. Revathi

    2014-01-01

    Full Text Available We propose and design a spiral photonic crystal fiber with elliptical air holes for achieving high birefringence, large nonlinearity, and negative dispersion. The structure is designed using chalcogenide glass (As2S3 for different ellipticity ratios of air holes in the cladding and the effect on various properties is observed. The proposed structure has birefringence of the order 10−2, nonlinearity of 26739.42 W−1 m−1, and dispersion of −1136.69 at 0.85 μm. An accurate numerical approach based on finite element method is used for the design and simulation of the structure. Due to high birefringence and negative dispersion, the proposed structure can be used for polarization control and dispersion compensation, respectively.

  15. Crystal growth of potassium 3,5-dinitrobenzoate (KDNB) for third order nonlinear optical (NLO) applications

    Science.gov (United States)

    Pandian, Muthu Senthil; Karuppasamy, P.; Ramasamy, P.

    2017-05-01

    The semi-organic nonlinear optical single crystals of potassium 3,5-dinitrobenzoate (KDNB) were grown by slow evaporation solution technique (SEST). The lattice parameters of the grown crystal were confirmed by single crystal X-ray diffraction analysis. The optical transmittance, cut-off wavelength and band gap of the KDNB crystal were obtained by UV-Vis NIR spectrum analysis. Vickers microhardness analysis was carried out to identify mechanical stability and work hardening co-efficient of the grown crystal. The crystalline perfection of the grown crystal was identified by chemical etching study using water as etchant. The third-order nonlinear optical properties such as nonlinear refractive index (n2), nonlinear absorption co-efficient (β) and third order nonlinear susceptibility (χ(3)) of KDNB crystal were evaluated using Z-scan technique at the wavelength of 632.8 nm.

  16. A Scanning Hologram Recorded by Phase Conjugate Property of Nonlinear Crystals

    DEFF Research Database (Denmark)

    Zi-Liang, Ping; Dalsgaard, Erik

    1996-01-01

    A methode of recording a scanning hologram with phase conjugate property of nonlinear crystal is provided. The principle of recording, setup and experiments are given.......A methode of recording a scanning hologram with phase conjugate property of nonlinear crystal is provided. The principle of recording, setup and experiments are given....

  17. Nonlinear radiation pressure dynamics in an optomechanical crystal

    CERN Document Server

    Krause, Alex G; Ludwig, Max; Safavi-Naeini, Amir H; Chan, Jasper; Marquardt, Florian; Painter, Oskar

    2015-01-01

    Utilizing a silicon nanobeam optomechanical crystal, we investigate the attractor diagram arising from the radiation pressure interaction between a localized optical cavity at $\\lambda = 1552$nm and a mechanical resonance at $\\omega/2\\pi = 3.72$GHz. At a temperature of $T \\approx 10$K, highly nonlinear driving of mechanical motion is observed via continuous wave optical pumping. Introduction of a time-dependent (modulated) optical pump is used to steer the system towards an otherwise inaccessible dynamically stable attractor in which mechanical self-oscillation occurs for an optical pump red-detuned from the cavity resonance. An analytical model incorporating thermo-optic effects due to optical absorption heating is developed, and found to accurately predict the measured device behavior.

  18. Enhanced Nonlinear Optical Effect in Hybrid Liquid Crystal Cells Based on Photonic Crystal

    Science.gov (United States)

    Bugaychuk, Svitlana; Iljin, Andrey; Lytvynenko, Oleg; Tarakhan, Ludmila; Karachevtseva, Lulmila

    2017-07-01

    Nonlinear-optical response of photorefractive hybrid liquid crystal (LC) cells has been studied by means of dynamic holographic technique in two-wave mixing arrangement. The LC cells include nonuniform silicon substrates comprising a micrometer-range photonic crystal. A thin LC layer is set between silicon substrate and a flat glass substrate covered by a transparent (ITO) electrode. A dynamic diffraction grating was induced in the LC volume by the two-wave mixing of laser beams with simultaneous application of DC electric field to the cell. Theoretical model of Raman-Nath self-diffraction was developed. This model allows for calculation of nonlinear optical characteristics in thin samples on the base of two-wave mixing experimental data, and with taking into account light losses on absorption and/or scattering. The hybrid LC cells demonstrate strong nonlinear optical effect, prospective for many applications in electro-optical microsystems, such as SLMs, as well as in multi-channel systems.

  19. Azimuthal and radial shaping of vortex beams generated in twisted nonlinear photonic crystals.

    Science.gov (United States)

    Shemer, Keren; Voloch-Bloch, Noa; Shapira, Asia; Libster, Ana; Juwiler, Irit; Arie, Ady

    2013-12-15

    We experimentally demonstrate that the orbital angular momentum (OAM) of a second harmonic (SH) beam, generated within twisted nonlinear photonic crystals, depends both on the OAM of the input pump beam and on the quasi-angular momentum of the crystal. In addition, when the pump's radial index is zero, the radial index of the SH beam is equal to that of the nonlinear crystal. Furthermore, by mixing two noncollinear pump beams in this crystal, we generate, in addition to the SH beams, a new "virtual beam" having multiple values of OAM that are determined by the nonlinear process.

  20. Optical scattering by a nonlinear medium, II: induced photonic crystal in a nonlinear slab of BBO

    CERN Document Server

    Godard, Pierre; Nicolet, Andre

    2010-01-01

    The purpose of this paper is to investigate the scattering by a nonlinear crystal whose depth is about the wavelength of the impinging field. More precisely, an infinite nonlinear slab is illuminated by an incident field which is the sum of three plane waves of the same frequency, but with different propagation vectors and amplitudes, in such a way that the resulting incident field is periodic. Moreover, the height of the slab is of the same order of the wavelength, and therefore the so-called slowly varying envelope approximation cannot be used. In our approach we take into account some retroactions of the scattered fields between them (for instance, we do not use the nondepletion of the pump beam). As a result, a system of coupled nonlinear partial differential equations has to be solved. To do this, the finite element method (FEM) associated with perfectly matched layers is well suited. Nevertheless, when using the FEM, the sources have to be located in the meshed area, which is of course impossible when d...

  1. Defects in Nonlinear Elastic Crystals: Differential Geometry, Finite Kinematics, and Second-Order Analytical Solutions

    Science.gov (United States)

    2015-04-01

    of dislocations in anisotropic crystals, Int. J. Eng. Sci. 5, 171–190 (1967). [92] A. Yavari and A. Goriely, Riemann -Cartan geometry of nonlinear...distributed point defects, Proc. R. Soc. Lond. A 468, 3902–3922 (2012). [94] A. Yavari and A. Goriely, Riemann -Cartan geometry of nonlinear disclination...ARL-RP-0522 ● APR 2015 US Army Research Laboratory Defects in Nonlinear Elastic Crystals: Differential Geometry , Finite

  2. Studies on Crystal Growth, Vibrational, Electronic Properties of Nonlinear Optical Crystal: Triglycine Phosphate

    Science.gov (United States)

    Meera, M. R.; Dipuna Das, C. N.; Bena Jothy, V.; Rayar, S. L.

    2016-10-01

    Nonlinear optics is a topic of much current interest that exhibits a great diversity. This is due to the technological potentials of certain nonlinear optical effects for photonic based technologies. Many NLO crystals grown by mixing amino acids with various organic and inorganic acids have been reported in the literature. Hence, glycine mixed semi-organic material will be of special interest as a fundamental building block to develop many complex crystals with improved NLO properties. In this context, the present work it is attempted to grow NLO active Triglycine phosphate [(NH2CH2COOH)3H3PO4](TGP) crystal from aqueous solution at room temperature by slow evaporation method. The geometry, intermolecular hydrogen bonding and harmonic vibrational wavenumbers of TGP was investigated with the help of B3LYP density functional theory (DFT) methods. Natural Bond Orbital (NBO) analysis confirms the occurrence of strong intermolecular N-H...O hydrogen bond. Second harmonic frequency generation was examined by Kurtz and Perry powder test. Theoretical first order hyperpolarizability value was calculated.

  3. Optical frequency conversion in quasi-phase-matched stacks of nonlinear crystals

    Science.gov (United States)

    Rustagi, K. C.; Mehendale, S. C.; Meenakshi, S.

    1982-06-01

    The paper presents a quantitative theory of nonlinear frequency conversion in stacks of crystals in which the phase mismatch due to dispersion is compensated by changing the sign of the nonlinear coupling coefficient in successive crystals. The effects of systematic and random departures in crystal lengths are studied with emphasis on the evolution of the relative phase. It is shown that with the appropriate choice of the signs of the nonlinear coupling coefficient in various crystals, high efficiency frequency conversion should be possible using almost any sufficiently large set of nonlinear crystals. In addition, the theory of second harmonic generation in periodic stacks and in rotating twinned crystals of zinc-blend structure is described.

  4. Crystal growth and comparison of vibrational and thermal properties of semi-organic nonlinear optical materials

    Indian Academy of Sciences (India)

    S Gunasekaran; G Anand; R Arun Balaji; J Dhanalakshmi; S Kumaresan

    2010-10-01

    Single crystals of urea thiourea mercuric sulphate (UTHS) and urea thiourea mercuric chloride (UTHC), semi-organic nonlinear optical materials, were grown by low-temperature solution growth technique by slow evaporation method using water as the solvent. Good quality single crystals were grown within three weeks. The nonlinear nature of the crystals was confirmed by SHG test. The UV–Vis spectrum showed the transmitting ability of the crystals in the entire visible region. FTIR spectrum was recorded and vibrational assignments were made. The degree of dopant inclusion was ascertained by AAS. The TGA–DTA studies showed the thermal properties of the crystals.

  5. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design...

  6. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design....

  7. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design....

  8. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design...

  9. Growth, spectroscopic, dielectric and nonlinear optical studies of semi organic nonlinear optical crystal - L-Alanine lithium chloride

    Science.gov (United States)

    Hanumantharao, Redrothu; Kalainathan, S.

    2012-02-01

    A new and efficient semi organic nonlinear optical crystal (NLO) from the amino acid family L-alanine lithium chloride (LAL) has been grown by slow evaporation technique from aqueous solution. The functional groups were identified from NMR spectral studies. Mass spectral analysis shows the molecular ion mass. Dielectric studies has been done for the grown crystal and relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.43 times that of standard potassium dihydrogen phosphate (KDP) crystals. The compound crystallized in non-centrosymmetric space group Pna21. The results have been discussed in detail.

  10. Growth, spectroscopic, dielectric and nonlinear optical studies of semi organic nonlinear optical crystal--L-alanine lithium chloride.

    Science.gov (United States)

    Hanumantharao, Redrothu; Kalainathan, S

    2012-02-01

    A new and efficient semi organic nonlinear optical crystal (NLO) from the amino acid family L-alanine lithium chloride (LAL) has been grown by slow evaporation technique from aqueous solution. The functional groups were identified from NMR spectral studies. Mass spectral analysis shows the molecular ion mass. Dielectric studies has been done for the grown crystal and relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.43 times that of standard potassium dihydrogen phosphate (KDP) crystals. The compound crystallized in non-centrosymmetric space group Pna21. The results have been discussed in detail.

  11. Enhanced nonlinear optical response of one-dimensional metal-dielectric photonic crystals.

    Science.gov (United States)

    Lepeshkin, Nick N; Schweinsberg, Aaron; Piredda, Giovanni; Bennink, Ryan S; Boyd, Robert W

    2004-09-17

    We describe a new type of artificial nonlinear optical material composed of a one-dimensional metal-dielectric photonic crystal. Because of the resonant nature of multiple Bragg reflections, the transmission within the transmission band can be quite large, even though the transmission through the same total thickness of bulk metal would be very small. This procedure allows light to penetrate into the highly nonlinear metallic layers, leading to a large nonlinear optical response. We present experimental results for a Cu/SiO(2) crystal which displays a strongly enhanced nonlinear optical response (up to 12X) in transmission.

  12. Nonlinear optical studies of liquid crystals and polymers

    Science.gov (United States)

    Hong, Seok-Cheol

    Polymers are indispensable in our life. A life is a continuous event maintained by many complex processes in which biological polymers participate. It also gets help from a variety of natural and synthetic polymers with useful functions. Such functions depend on the chemical and conformational structures of polymers and often largely on the surface structures and properties of polymers. We used second order nonlinear optical techniques (sum frequency vibrational spectroscopy (SFVS) and second harmonic generation (SHG)) to obtain structural information on polymers. We also studied liquid crystal molecules deposited on polymer surfaces. The first part of the thesis is aimed at understanding liquid crystal (LC) alignment on rubbed polymer surfaces by determining the molecular orientations of LC adsorbates and surface polymer chains. The alignment of LCs by rubbed polymers is not only of fundamental interest but also of practical importance because it is a technique enabling production of commercial liquid crystal displays. We observed that rubbing induces alignment of surface polymer chains along the rubbing direction, and there is a strong correlation between the molecular orientations of LC adsorbates and the surface chains of rubbed polymers such as polyvinyl alcohol (PVA) and polyimide (6FDA-6CBO). The latter revealed a relatively large but negative pretilt angle, which is highly unusual. On a rubbed polystyrene (PS) surface, we found that the phenyl side groups of PS are oriented perpendicularly to the rubbing direction at the surface, rendering an LC alignment also perpendicular to the rubbing direction. The second part of the thesis is our discovery of rubbing-induced polar ordering on nylon 11 surfaces. Nylon 11 is known to be ferroelectric. We found that mechanical rubbing can induce strong ferroelectric polarization on an initially amorphous film of nylon 11. The surface chains of rubbed nylon 11 are aligned along the rubbing direction while the induced

  13. Growth and characterization of a third order nonlinear optical single crystal: Ethylenediamine-4-nitrophenolate monohydrate

    Energy Technology Data Exchange (ETDEWEB)

    Dhanalakshmi, B. [Department of Physics, Asan Memorial College of Engineering and Technology, Chengalpattu 603 203, Tamil Nadu (India); Ponnusamy, S., E-mail: suruponnus@gmail.com [Center for Materials Science and Nano Devices, Department of Physics, SRM University, Kattankulathur 603 203, Tamil Nadu (India); Muthamizhchelvan, C.; Subhashini, V. [Center for Materials Science and Nano Devices, Department of Physics, SRM University, Kattankulathur 603 203, Tamil Nadu (India)

    2015-10-15

    Highlights: • EDA4NPH crystal possesses negative nonlinear refractive index. • The crystal exhibits high third-order NLO susceptibility. • Wide transparency of the crystal makes it suitable for NLO applications. • Dielectric studies substantiate the suitability for electro-optic applications. • The crystal possesses suitable mechanical strength for device fabrication. - Abstract: Bulk crystals of the charge-transfer complex, ethylenediamine-4-nitrophenolate monohydrate, were grown by slow solvent evaporation method from aqueous solution at room temperature. The X-ray diffraction measurements showed that the crystal belongs to centrosymmetric space group C2/c of monoclinic system. The functional groups in the complex were identified using FTIR, FTRaman and FTNMR analyses. The Z-scan measurements revealed the negative nonlinear refractive index of the crystal. The nonlinear absorption coefficient and third order nonlinear optical susceptibility calculated from the measurements were −3.5823 × 10{sup −3} cm/W and 2.3762 × 10{sup −6} esu respectively. The crystal was shown to be highly transparent above 366 nm by UV–vis spectroscopy and a yellow fluorescence was observed from PL spectrum. The TG–DTA and DSC analyses showed that the crystal is thermally stable up to 117.4 °C. The crystals were characterized by dielectric, etching and microhardness studies.

  14. Terahertz Generation in Nonlinear Crystals with Mid-Infrared CO2 Laser

    Institute of Scientific and Technical Information of China (English)

    LU Yan-Zhao; WANG Xin-Bing; MIAO Liang; ZUO Du-Luo; CHENG Zu-Hai

    2011-01-01

    The terahertz(THz)generation based on difference frequency generation in nonlinear optical crystals pumped by mid-infrared C02 laser has been investigated.We present a comprehensive study of the phase-matching conditions in the GaSe, ZnGeP2 and GaAs crystals. A comparison of the characteristics of these crystals as the THz frequency generator is also presented. The investigation of the conversion efficiency shows that GaSe and GaAs are the most promising nonlinear crystals for the efficient and widely tunable THz generation.

  15. Soliton compression to few-cycle pulses using quadratic nonlinear photonic crystal fibers: A design study

    DEFF Research Database (Denmark)

    Bache, Morten; Moses, Jeffrey; Lægsgaard, Jesper;

    2007-01-01

    We show theoretically that high-quality soliton compression from ~500 fs to ~10 fs is possible in poled silica photonic crystal fibers using cascaded (2):(2) nonlinearities. A moderate group-velocity mismatch optimizes the compression.......We show theoretically that high-quality soliton compression from ~500 fs to ~10 fs is possible in poled silica photonic crystal fibers using cascaded (2):(2) nonlinearities. A moderate group-velocity mismatch optimizes the compression....

  16. Growth and Solvent Effects of a Promising Nonlinear Optical Sodium Paranitrophenolate Dihydrate (NO2-C6H4-ONa·2H2O) Single Crystal

    Institute of Scientific and Technical Information of China (English)

    B.Milton Boaz; A.Leyo Rajesh; S. Xavier Jesu Raja; S. Jerome Das

    2004-01-01

    Sodium paranitrophenolate dihydrate (NPNa·2H2O) is an excellent semiorganic nonlinear optical (NLO) material, crystallizes both in water and methanol with high degree of transparency. Good optical quality single crystals of dimension upto 18 mmx6 mmx3 mm are obtained by isothermal solvent evaporation technique. The solubility of the crystal in different solvents was measured gravimetrically. The single crystals of NPNa·2H2O show variation in physical properties and growth rate in different solvents. Methanol or ethanol solution yields crystals of bipyramidal shape with clear morphology. However, methanol grown crystal is exhibiting improved hardness parameters and possesses excellent thermal stability as compared to water grown crystals. The effects of solvent on hardness parameter along with thermal and optical properties of NPNa·2H2O was revealed in this paper.

  17. Linear and nonlinear modeling of light propagation in hollow-core photonic crystal fiber

    DEFF Research Database (Denmark)

    Roberts, John; Lægsgaard, Jesper

    2009-01-01

    Hollow core photonic crystal fibers (HC-PCFs) find applications which include quantum and non-linear optics, gas detection and short high-intensity laser pulse delivery. Central to most applications is an understanding of the linear and nonlinear optical properties. These require careful modeling...

  18. Multiple-μJ mid-IR supercontinuum generation in quadratic nonlinear crystals

    DEFF Research Database (Denmark)

    Bache, Morten; Zhou, Binbin; Ashihara, S.

    2016-01-01

    Pumping a quadratic nonlinear crystal in the mid-IR we observe octave-spanning mid-IR supercontinua. A self-acting cascaded process leads to the formation of a self-defocusing nonlinearity, allowing formation of filament-free octave-spanning supercontinua in the 2.0–7.0 μm range with 10s of μ...

  19. Enhanced nonlinearity in photonic crystal fiber by germanium doping in the core region

    Institute of Scientific and Technical Information of China (English)

    Tingting Sun; Guiyun Kai; Zhi Wang; Shuzhong Yuan; Xiaoyi Dong

    2008-01-01

    Germanium doping in silica can be used as a method for nonlinearity enhancement.Properties of the enhanced nonlinearity in photonic crystal fiber(PCF)with a GeO2-doped core are investigated theoretically by using all-vector finite element method.Numerical result shows that the nonlinear coefficient of PCF is greatly enhanced with increasing doping concentration,furthermore,optimal radius of the doped region should be considered for the desired operating wavelength.

  20. Growth and characterization of an organic nonlinear optical crystal: Glycinium trichloroacetate

    Energy Technology Data Exchange (ETDEWEB)

    Peter, M. Esthaku [Department of Physics, Easwari Engineering College, Chennai 600089 (India); Ramasamy, P., E-mail: proframasamy@hotmail.com [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603110 (India)

    2012-11-15

    Single crystal of glycinium trichloroacetate, an organic nonlinear optic (NLO) material, has been grown by slow solvent evaporation technique at room temperature. The grown crystal was subjected to single crystal X-ray diffraction for confirming the coordination formed, and the presence of various functional groups was studied by FTIR in the range 4000-450 cm{sup -1}. UV-Visible transmittance studies were performed to analyze optical transparency of the crystal and second harmonic generation was investigated to explore the NLO property of the material. Thermogravimetric and differential thermal analysis have been performed to study thermal properties of the grown crystal. Dielectric constant and dielectric loss were studied at different temperatures and frequencies. Vicker's microhardness testing was carried out on the as grown crystal to reveal the mechanical properties of the crystal. Etching studies were made on the as grown crystal to analyze the structural imperfection of the crystal.

  1. NONLINEAR OPTICAL MOLECULAR CRYSTAL BASED ON 2,6-DIAMINOPYRIDINE: SYNTHESIS AND CHARACTERIZATION

    Directory of Open Access Journals (Sweden)

    I. M. Pavlovetc

    2014-05-01

    Full Text Available The paper deals with investigation of a new nonlinear optical material based on nonlinear optical chromophore (4-Nitrophenol and aminopyridine (2,6-Diaminopyridine. Calculation results are presented for molecular packing in the crystalline compound, based on the given components. According to these results the finite material must have a noncentrosymmetric lattice, which determines the presence of the second order nonlinear optical response. Investigations carried out in this work confirm these calculations. Results of experiments are given describing the co-crystallization of these components and the following re-crystallization of the obtained material. In order to get a monocrystal form, the optimal conditions for the synthesis of molecular crystals based on these components are determined. Sufficiently large homogeneous crystals are obtained, that gave the possibility to record their spectra in the visible and near infrared parts of the spectrum, to determine their nonlinear optical properties and the level of homogeneity. Their optical (optical transmission and optical laser damage threshold and nonlinear optical properties are presented. For observation and measurement of the nonlinear optical properties an installation was built which implements the comparative method for measurements of nonlinear optical properties. A potassium titanyl oxide phosphate crystal was used as a sample for comparison. Results are given for the conversion efficiency of the primary laser radiation in the second optical harmonic relative to the signal obtained on the potassium titanyl oxide phosphate crystal. Obtained results show that the molecular co-crystal based on 2,6-Diaminopyridine is a promising nonlinear optical material for generating the second optical harmonic on the Nd: YAG laser (532 nm.

  2. Influence of boron concentration on nonlinear absorption and ultrafast dynamics in GaSe crystals

    Science.gov (United States)

    Karatay, Ahmet; Yuksek, Mustafa; Ertap, Hüseyin; Mak, Ali Kemal; Karabulut, Mevlüt; Elmali, Ayhan

    2016-10-01

    The nonlinear absorption properties and ultrafast dynamics of pure and boron doped GaSe crystals have been studied by open aperture Z-scan and ultrafast pump probe spectroscopy techniques. All of the studied crystals showed nonlinear absorption under 100 fs pulse duration and 1200 nm wavelength excitations. Nonlinear absorption coefficients increase with increasing the doping ratio of boron atoms in crystals. These findings indicate that free carrier density increase with boron doping and this behavior leads to excited state absorption. Second harmonic generation signals of crystals were detected with the help of fiber optic spectrometer. The blue shift in the energy of the second harmonic generation signals was observed in boron doped crystals. Ultrafast pump probe experiments indicate that the excited state absorption signal with long lifetime observed for undoped GaSe crystal switches to bleach signal for boron doped GaSe crystals at 625 nm probe wavelength. The effects of increasing doping ratio were observed on ultrafast dynamics as a switching time changes. Our experimental results indicate that it is possible to control nonlinear absorption properties, frequency conversion and ultrafast dynamics of GaSe crystal by changing boron doping ratio.

  3. The nonlinear optical response of a two-dimensional atomic crystal

    CERN Document Server

    Merano, Michele

    2015-01-01

    The theory of Bloembergen and Persham for the light waves at the boundary of nonlinear media is applied to a nonlinear two-dimensional atomic crystal placed in between linear bulk media. The crystal is treated as a zero-thickness interface, a real two-dimensional system. Harmonic waves emanate from it. Generalization of the laws of reflection and refraction give the direction and the intensity of the harmonic waves. The nonlinear polarization of these special materials is very sensitive to the substrate on which they are deposited. Experiments on second harmonic generation of a $\\rm MoS_{2}$ monolayer are discussed to elucidate this point.

  4. Crystal growth and characterizations of L-cystine dihydrobromide—A semiorganic nonlinear optical material

    Science.gov (United States)

    Anbuchezhiyan, M.; Ponnusamy, S.; Muthamizhchelvan, C.

    2010-02-01

    Single crystal of a new semiorganic nonlinear optical material, L-cystine dihydrobromide, was grown successfully from aqueous solution by slow evaporation method. The grown crystals were characterized by single crystal X-ray diffraction technique to determine the cell parameters. Powder X-ray diffraction analysis also confirms the structure of the grown title compound. The functional groups and vibrational frequencies have been identified using FTIR and FT Raman spectral data. Transmittance of the title compound was analyzed using UV-Vis spectrum. The mechanical strength of the grown crystal was found using Vickers microhardness measurement. The thermal stability of the grown crystal was determined with the aid of thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Second order nonlinear optical behavior of the grown crystal has been confirmed by Kurtz powder second harmonic generation (SHG) test and its SHG efficiency was found as deff=0.38 deff (KDP).

  5. Crystal growth and characterizations of L-cystine dihydrobromide-A semiorganic nonlinear optical material

    Energy Technology Data Exchange (ETDEWEB)

    Anbuchezhiyan, M. [Department of Physics, Valliammai Engineering College, S.R.M. Nagar, Kattankulathur 603 203, Chennai (India); Ponnusamy, S., E-mail: suruponnus@gmail.co [Centre for Material Science and Nano Devices, Department of Physics, SRM University, Kattankulathur 603 203, Chennai (India); Muthamizhchelvan, C. [Centre for Material Science and Nano Devices, Department of Physics, SRM University, Kattankulathur 603 203, Chennai (India)

    2010-02-15

    Single crystal of a new semiorganic nonlinear optical material, L-cystine dihydrobromide, was grown successfully from aqueous solution by slow evaporation method. The grown crystals were characterized by single crystal X-ray diffraction technique to determine the cell parameters. Powder X-ray diffraction analysis also confirms the structure of the grown title compound. The functional groups and vibrational frequencies have been identified using FTIR and FT Raman spectral data. Transmittance of the title compound was analyzed using UV-Vis spectrum. The mechanical strength of the grown crystal was found using Vickers microhardness measurement. The thermal stability of the grown crystal was determined with the aid of thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Second order nonlinear optical behavior of the grown crystal has been confirmed by Kurtz powder second harmonic generation (SHG) test and its SHG efficiency was found as d{sub eff}=0.38d{sub eff} (KDP).

  6. Growth, spectral, optical, thermal, crystallization perfection and nonlinear optical studies of novel nonlinear optical crystal—Urea thiosemicarbazone monohydrate

    Science.gov (United States)

    Hanumantharao, Redrothu; Kalainathan, S.; Bhagavannarayana, G.

    2012-06-01

    Single crystals of organic nonlinear material urea thiosemicarbazone monohydrate (UTM) have been grown by slow evaporation method. The grown crystals were characterized by single crystal X-ray diffraction analysis reveals that sample crystallized in triclinic system with noncentrosymmetric space group P1. Powder XRD pattern confirmed that grown crystal posses highly crystalline nature. FTIR spectrum was recorded to identify the presence of functional groups and molecular structure was confirmed by 1H NMR spectrum. Material confirmation of title compound has been performed by using mass spectroscopic analysis. Elemental composition of grown crystal was confirmed by energy-dispersive spectrometry (EDS). To study the crystalline perfection of the grown crystals, high-resolution X-ray diffraction (HR-XRD) study was carried out. Thermogravimetric and differential thermal analyses were employed to understand the thermal and physio-chemical stability of the synthesized compound. UV-Vis-NIR spectrum revealed the transmission properties of the crystal specimen. Relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.89 times that of standard potassium dihydrogen phosphate (KDP) crystals.

  7. High confinement, high yield Si3N4 waveguides for nonlinear optical application

    CERN Document Server

    Epping, Jörn P; Mateman, Richard; Leinse, Arne; Heideman, René G; van Rees, Albert; van der Slot, Peter J M; Lee, Chris J; Boller, Klaus-J

    2014-01-01

    In this paper we present a novel fabrication technique for silicon nitride (Si3N4) waveguides with a thickness of up to 900 nm, which are suitable for nonlinear optical applications. The fabrication method is based on etching trenches in thermally oxidized silicon and filling the trenches with Si3N4. Using this technique no stress-induced cracks in the Si3N4 layer were observed resulting in a high yield of devices on the wafer. The propagation losses of the obtained waveguides were measured to be as low as 0.4 dB/cm at a wavelength of around 1550 nm.

  8. Production yield of rare-earth ions implanted into an optical crystal

    Energy Technology Data Exchange (ETDEWEB)

    Kornher, Thomas, E-mail: t.kornher@physik.uni-stuttgart.de; Xia, Kangwei; Kolesov, Roman; Reuter, Rolf; Villa, Bruno; Wrachtrup, Jörg [3. Physikalisches Institut, Universität Stuttgart, 70569 Stuttgart (Germany); Kukharchyk, Nadezhda; Wieck, Andreas D. [Angewandte Festkörperphysik, Ruhr-Universität Bochum, 44780 Bochum (Germany); Siyushev, Petr [Universität Ulm, Institut für Quantenoptik, 89081 Ulm (Germany); Stöhr, Rainer [3. Physikalisches Institut, Universität Stuttgart, 70569 Stuttgart (Germany); Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Schreck, Matthias [Experimentalphysik IV, Universität Augsburg, 86159 Augsburg (Germany); Becker, Hans-Werner [RUBION, Ruhr-Universität Bochum, 44780 Bochum (Germany)

    2016-02-01

    Rare-earth (RE) ions doped into desired locations of optical crystals might enable a range of novel integrated photonic devices for quantum applications. With this aim, we have investigated the production yield of cerium and praseodymium by means of ion implantation. As a measure, the collected fluorescence intensity from both implanted samples and single centers was used. With a tailored annealing procedure for cerium, a yield up to 53% was estimated. Praseodymium yield amounts up to 91%. Such high implantation yield indicates a feasibility of creation of nanopatterned rare-earth doping and suggests strong potential of RE species for on-chip photonic devices.

  9. Cesium hafnium chloride: A high light yield, non-hygroscopic cubic crystal scintillator for gamma spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Burger, Arnold, E-mail: aburger@fisk.edu [Department of Life and Physical Sciences, Fisk University, Nashville, Tennessee 37208 (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States); Rowe, Emmanuel; Groza, Michael; Morales Figueroa, Kristle [Department of Life and Physical Sciences, Fisk University, Nashville, Tennessee 37208 (United States); Cherepy, Nerine J.; Beck, Patrick R.; Hunter, Steven; Payne, Stephen A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2015-10-05

    We report on the scintillation properties of Cs{sub 2}HfCl{sub 6} (cesium hafnium chloride or CHC) as an example of a little-known class of non-hygroscopic compounds having the generic cubic crystal structure of K{sub 2}PtCl{sub 6}. The crystals are easily growable from the melt using the Bridgman method with minimal precursor treatments or purification. CHC scintillation is centered at 400 nm, with a principal decay time of 4.37 μs and a light yield of up to 54 000 photons/MeV when measured using a silicon CCD photodetector. The light yield is the highest ever reported for an undoped crystal, and CHC also exhibits excellent light yield nonproportionality. These desirable properties allowed us to build and test CHC gamma-ray spectrometers providing energy resolution of 3.3% at 662 keV.

  10. Nonlinear continuous-wave optical propagation in nematic liquid crystals: Interplay between reorientational and thermal effects

    Science.gov (United States)

    Alberucci, Alessandro; Laudyn, Urszula A.; Piccardi, Armando; Kwasny, Michał; Klus, Bartlomiej; Karpierz, Mirosław A.; Assanto, Gaetano

    2017-07-01

    We investigate nonlinear optical propagation of continuous-wave (CW) beams in bulk nematic liquid crystals. We thoroughly analyze the competing roles of reorientational and thermal nonlinearity with reference to self-focusing/defocusing and, eventually, the formation of nonlinear diffraction-free wavepackets, the so-called spatial optical solitons. To this extent we refer to dye-doped nematic liquid crystals in planar cells excited by a single CW beam in the highly nonlocal limit. To adjust the relative weight between the two nonlinear responses, we employ two distinct wavelengths, inside and outside the absorption band of the dye, respectively. Different concentrations of the dye are considered in order to enhance the thermal effect. The theoretical analysis is complemented by numerical simulations in the highly nonlocal approximation based on a semi-analytic approach. Theoretical results are finally compared to experimental results in the Nematic Liquid Crystals (NLC) 4-trans-4'-n-hexylcyclohexylisothiocyanatobenzene (6CHBT) doped with Sudan Blue dye.

  11. Investigation of unidirectional growth and characterization of nonlinear optical L-alaninium p-toluenesulfonate crystal

    Science.gov (United States)

    Thayanithi, V.; Rajesh, K.; Praveen Kumar, P.

    2017-08-01

    An aminoacid nonlinear optical crystal of L-alaninium p-toluenesulfonate (LAPT) was grown by Sankaranarayanan and Ramasamy (SR) method. The seed crystal of LAPT was grown with the help of a conventional solution method. The size of the grown crystal is 50 mm length and 20 mm diameter for (0 1 0) plane. The solubility of LAPT was determined in deionized water. The grown LAPT crystal belongs to the orthorhombic crystal system with noncentrosymmetric space group P212121. The morphology of the grown LAPT crystal reveals a hexagonal shape with six facet. The lower cut-off wavelength of the grown crystal is found to be 285 nm. Optical transmittance of the crystal grown by SR method is increased by 20%, when compared with the conventionally grown crystal. The LDT value of the SR-grown LAPT crystal has increased by 0.57 GW cm-2, compared with LAPT crystal grown by conventional method. The emission spectra of the grown crystal was analysed by photoluminescence analysis. The mechanical strength of the grown LAPT crystal was analysed by using Vickers hardness test, and the work hardening coefficient (n) of the LAPT crystal grown by SR method is found to be 2.20. The second harmonic generation efficiency of the LAPT crystal is 2.1 times that of KDP.

  12. Crystal structure, growth and nonlinear optical studies of isonicotinamide p-nitrophenol: A new organic crystal for optical limiting applications

    Science.gov (United States)

    Vijayalakshmi, A.; Vidyavathy, B.; Vinitha, G.

    2016-08-01

    Isonicotinamide p-nitrophenol (ICPNP), a new organic material, was synthesized using methanol solvent. Single crystals of ICPNP were grown using a slow evaporation solution growth technique. Crystal structure of ICPNP is elucidated by single crystal X-ray diffraction analysis. It belongs to monoclinic crystal system with space group of P21/c. It forms two dimensional networks by O-H…O, N-H…O and C-H…O hydrogen bonds. The molecular structure of ICPNP was further confirmed by Fourier transform infrared (FTIR) spectral analysis. The optical transmittance range and the lower cut-off wavelength (421 nm) with the optical band gap (2.90 eV) of the ICPNP crystal were determined by UV-vis-NIR spectral study. Thermal behavior of ICPNP was studied by thermo gravimetric and differential thermal analyses (TG/DTA). The relative dielectric permittivity was calculated for various temperature ranges. Laser damage threshold of ICPNP crystal was found to be 1.9 GW/cm2 using an Nd:YAG laser. A Z-scan technique was employed to measure the nonlinear absorption coefficient, nonlinear refractive index and nonlinear optical susceptibility. Optical limiting behavior of ICPNP was observed at 35 mW input power.

  13. Highly efficient single-pass sum frequency generation by cascaded nonlinear crystals

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Andersen, Peter E.; Jensen, Ole Bjarlin;

    2015-01-01

    , despite differences in the phase relations of the involved fields. An unprecedented 5.5 W of continuous-wave diffraction-limited green light is generated from the single-pass sum frequency mixing of two diode lasers in two periodically poled nonlinear crystals (conversion efficiency 50%). The technique......The cascading of nonlinear crystals has been established as a simple method to greatly increase the conversion efficiency of single-pass second-harmonic generation compared to a single-crystal scheme. Here, we show for the first time that the technique can be extended to sum frequency generation...... is generally applicable and can be applied to any combination of fundamental wavelengths and nonlinear crystals....

  14. Physical, optical and nonlinear properties of InS single crystal

    Science.gov (United States)

    Kushwaha, Pallavi; Patra, Anuradha; Anjali, E.; Surdi, Harshad; Singh, Abhishek; Gurada, C.; Ramakrishnan, S.; Prabhu, S. S.; Gopal, Achanta Venu; Thamizhavel, A.

    2014-01-01

    Indium Sulphide (InS) single crystals are successfully grown by In flux. Single crystal X-ray diffraction shows orthorhombic structure of Pnnm space group. Ellipsometry measurements performed on the (0 1 0) oriented crystal exhibit low anisotropy in the 300-1000 nm wavelength range and consequently negligible THz transmission is observed. Optical band gap of 2.09 eV is deduced from linear optical measurements. Nonlinear optical properties are studied by single beam Z-scan measurements at 800 nm, where two-photon absorption is present. Nonlinear refractive index and absorption coefficient are estimated to be n2 = 2.3 × 10-11 cm2/W and β = 62.4 cm/GW, respectively for excitation intensity of 0.32 GW/cm2. The origin of nonlinearity in InS crystal is accounted to be due to the third-order anharmonic motion of the bound electrons.

  15. Shear dependent nonlinear vibration in a high quality factor single crystal silicon micromechanical resonator

    Science.gov (United States)

    Zhu, H.; Shan, G. C.; Shek, C. H.; Lee, J. E.-Y.

    2012-07-01

    The frequency response of a single crystal silicon resonator under nonlinear vibration is investigated and related to the shear property of the material. The shear stress-strain relation of bulk silicon is studied using a first-principles approach. By incorporating the calculated shear property into a device-level model, our simulation closely predicts the frequency response of the device obtained by experiments and further captures the nonlinear features. These results indicate that the observed nonlinearity stems from the material's mechanical property. Given the high quality factor (Q) of the device reported here (˜2 × 106), this makes it highly susceptible to such mechanical nonlinear effects.

  16. MECHANISM OF OPTICAL NONLINEARITY IN “LYOTROPIC LIQUID CRYSTAL — VIOLOGEN” SYSTEM

    Directory of Open Access Journals (Sweden)

    Hanna Bordyuh

    2014-06-01

    Full Text Available In the present work we analyze the characteristics of holographic grating recording and consider a mechanism of optical nonlinearity in the lyotropic liquid crystal (LLC — viologen samples. Taking into account structural and electrooptical properties of the admixture molecules it is possible to suggest that the recording is realized due to the change of polarizability of π-electron system of coloured viologen derivatives under the action of laser radiation. The main nonlinear optical parameters such as nonlinear refraction coefficient n2, cubic nonlinear susceptibility χ(3, and hyperpolarizability γ were calculated.

  17. Yield Improvement and Advanced Defect Control——Driving Forces for Modeling of Bulk Crystal Growth

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Yield improvement and advanced defect control can be identified as the driving forces for modeling of industrial bulk crystal growth. Yield improvement is mainly achieved by upscaling of the whole crystal growth apparatus and increased processing windows with more tolerances for parameter variations. Advanced defect control means on one hand a reduction of the number of deficient crystal defects and on the other hand the formation of beneficial crystal defects with a uniform distribution and well defined concentrations in the whole crystal. This "defect engineering" relates to the whole crystal growth process as well as the following cooling and optional annealing processes, respectively. These topics were illustrated in the paper by examples of modeling and experimental results of bulk growth of silicon (Si), gallium arsenide (GaAs), indium phosphide (InP) and calcium fluoride (CaF2). These examples also involve the state of the art of modeling of the most important melt growth techniques, crystal pulling (Czochralski methods) and vertical gradient freeze (Bridgman-type methods).

  18. A nonlinear dynamical system approach for the yielding behaviour of a viscoplastic material.

    Science.gov (United States)

    Burghelea, Teodor; Moyers-Gonzalez, Miguel; Sainudiin, Raazesh

    2017-02-15

    A nonlinear dynamical system model that approximates a microscopic Gibbs field model for the yielding of a viscoplastic material subjected to varying external stresses recently reported in R. Sainudiin, M. Moyers-Gonzalez and T. Burghelea, Soft Matter, 2015, 11(27), 5531-5545 is presented. The predictions of the model are in fair agreement with microscopic simulations and are in very good agreement with the micro-structural semi-empirical model reported in A. M. V. Putz and T. I. Burghelea, Rheol. Acta, 2009, 48, 673-689. With only two internal parameters, the nonlinear dynamical system model captures several key features of the solid-fluid transition observed in experiments: the effect of the interactions between microscopic constituents on the yield point, the abruptness of solid-fluid transition and the emergence of a hysteresis of the micro-structural states upon increasing/decreasing external forces. The scaling behaviour of the magnitude of the hysteresis with the degree of the steadiness of the flow is consistent with previous experimental observations. Finally, the practical usefulness of the approach is demonstrated by fitting a rheological data set measured with an elasto-viscoplastic material.

  19. Analysis of S Wave Propagation Through a Nonlinear Joint with the Continuously Yielding Model

    Science.gov (United States)

    Cui, Zhen; Sheng, Qian; Leng, Xianlun

    2017-01-01

    Seismic wave propagation through joints that are embedded in a rock mass is a critical issue for aseismic issues of underground rock engineering. Few studies have investigated nonlinear joints with a continuously yielding model. In this paper, a time-domain recursive method (TDRM) for an S wave across a nonlinear Mohr-Coulomb (MC) slip model is extended to a continuously yielding (CY) model. Verification of the TDRM-based results is conducted by comparison with the simulated results via a built-in model of 3DEC code. Using parametric studies, the effect of normal stress level, amplitude of incident wave, initial joint shear stiffness, and joint spacing is discussed and interpreted for engineering applications because a proper in situ stress level (overburden depth) and acceptable quality of surrounding rock mass are beneficial for seismic stability issues of underground rock excavation. Comparison between the results from the MC model and the CY model is presented both for an idealized impulse excitation and a real ground motion record. Compared with the MC model, complex joint behaviors, such as tangential stiffness degradation, normal stress dependence, and the hysteresis effect, that occurred in the wave propagation can be described with the CY model. The MC model seems to underestimate the joint shear displacement in a high normal stress state and in a real ground motion excitation case.

  20. Dispersion of the nonlinear refractive index of optical crystals

    Science.gov (United States)

    Adair, Robert; Chase, L. L.; Payne, Stephen A.

    1992-09-01

    The nonlinear refractive indices of several important optical materials have been measured at the second and third harmonic wavelengths of the Nd laser using nearly degenerate four-wave mixing. Measurements made relative to the nonlinear index of fused silica have the highest accuracy. Absolute measurements were also made using the Raman cross-section of benzene as a nonlinear reference standard. The relative measurements are compared with a despersion model base on parameters fitted to the linear refractive indicies and also to a recently proposed model based on Kramers-Kronig transformation of the calculated, two-band, two-photon loss spectrum.

  1. Growth and characterization of L-alanine cadmium bromide a semiorganic nonlinear optical crystals

    Science.gov (United States)

    Ilayabarathi, P.; Chandrasekaran, J.

    2012-10-01

    A new semiorganic nonlinear optical crystal, L-alanine cadmium bromide (LACB) was grown from aqueous solution by slow solvent evaporation method at room temperature. As grown crystals were characterized for its spectral, thermal, linear and second order nonlinear optical properties. LACB crystallizes in orthorhombic system and unit cell parameters a = 5.771(2) Å, b = 6.014(4) Å, c = 12.298(2) Å, α = β = γ = 90° and volume = 426.8(3) Å3. The mode of vibrations of different molecular groups present in the crystal was identified by FTIR study. The grown crystals were found to be transparent in the entire visible region. The thermal strength and the decomposition of the grown crystals were studied using TG/DTA and DSC analysis. Dielectric measurement revealed that the crystals had very low dielectric constant at higher frequency in room temperature. The mechanical behavior was studied by Vicker's microhardness tester. The grown crystal has negative photoconductivity nature. The fluorescence spectrum of the crystal was recorded and its optical band gap is about 3.356 eV. The NLO property of crystal using modified Kurtz-Perry powder technique with Nd:YAG laser light of wavelength 1064 nm indicated that their second harmonic generation (SHG) efficiency was half that of pure KDP.

  2. Group-velocity matched nonlinear photonic crystal fibers

    DEFF Research Database (Denmark)

    Bache, Morten; Lægsgaard, Jesper; Bang, Ole

    2006-01-01

    A quadratic nonlinear index-guiding silica PCF is optimized for efficient second-harmonic generation through dispersion calculations. Zero group-velocity mismatch is possible for any pump wavelength above 780 nm. Very high conversion efficiencies and bandwidths are found.......A quadratic nonlinear index-guiding silica PCF is optimized for efficient second-harmonic generation through dispersion calculations. Zero group-velocity mismatch is possible for any pump wavelength above 780 nm. Very high conversion efficiencies and bandwidths are found....

  3. Studies on lithium L-ascorbate dihydrate: An interesting chiral nonlinear optical crystal

    Energy Technology Data Exchange (ETDEWEB)

    Raghavendra Rao, K., E-mail: krrao@physics.iisc.ernet.in [Department of Physics, Indian Institute of Science, Bangalore 560012 (India); Bhat, H.L. [Department of Physics, Indian Institute of Science, Bangalore 560012 (India); Centre for Soft Matter Research, Jalahalli, Bangalore 560013 (India); Elizabeth, Suja [Department of Physics, Indian Institute of Science, Bangalore 560012 (India)

    2013-01-15

    Lithium L-Ascorbate dihydrate (LLA) is a new metal organic nonlinear optical crystal belonging to the saccharide family. Single crystals of LLA were grown from aqueous solution. Solubility of the crystal has a positive temperature coefficient facilitating growth by slow cooling. Rietveld refinement was used to confirm the phase formation. The crystal has prismatic habit with (010), (001) and (10-1) prominent faces. Thermal analysis shows that the crystal is stable up to 102 Degree-Sign C. Transmission spectrum of the crystal extends from 302 nm to 1600 nm. Dielectric spectroscopic analysis revealed Cole-Cole behaviour and prominent piezoelectric resonance peaks were observed in the range of 100-200 kHz. Second harmonic generation (SHG) conversion efficiency of up to 2.56 times that of a phase matched KDP crystal was achieved when the (010) plate of LLA single crystal was rotated about the +ve c axis, by 9.4 Degree-Sign in the clockwise direction. We also observed SHG conical sections which were attributed to noncollinear phase matching. The observation of the third conical section suggests very high birefringence and large nonlinear coefficients. A detailed study of surface laser damage showed that the crystal has high multiple damage thresholds of 9.7 GW cm{sup -2} and 4.2 GW cm{sup -2} at 1064 nm and 532 nm radiation respectively. Highlights: Black-Right-Pointing-Pointer Large nonlinear optical lithium L-ascorbate dihydrate crystals. Black-Right-Pointing-Pointer Crystals exhibit dielectric Cole-Cole behaviour and piezoelectric resonance. Black-Right-Pointing-Pointer Intense collinear and noncollinear second harmonic generation is observed. Black-Right-Pointing-Pointer Crystals possess high surface laser damage thresholds.

  4. RETRACTED: Crystal growth and spectroscopic characterization of Aloevera amino acid added lithium sulfate monohydrate: A non-linear optical crystal

    Science.gov (United States)

    Manimekalai, R.; Antony Joseph, A.; Ramachandra Raja, C.

    2014-03-01

    This article has been retracted: please see Elsevier Policy on Article Withdrawal. This article has been retracted at the request of authors. According to the author we have reported Aloevera Amino Acid added Lithium sulphate monohydrate [AALSMH] crystal is a new nonlinear optical crystal. From the recorded high performance liquid chromatography spectrum, by matching the retention times with the known compounds, the amino acids present in our extract are identified as homocystine, isoleucine, serine, leucine and tyrosine. From the thin layer chromatography and colorimetric estimation techniques, presence of isoleucine was identified and it was also confirmed by NMR spectrum. From the above studies, we came to conclude that AALSMH is new nonlinear optical crystal. After further investigation, lattice parameter values of AALSMH are coinciding with lithium sulphate. Therefore we have decided to withdraw our paper. Sorry for the inconvenience and time spent.

  5. Crystal growth and characterization of third order nonlinear optical piperazinium bis(4-hydroxybenzenesulphonate) (P4HBS) single crystal

    Science.gov (United States)

    Pichan, Karuppasamy; Muthu, Senthil Pandian; Perumalsamy, Ramasamy

    2017-09-01

    The organic single crystal of piperazinium bis(4-hydroxybenzenesulphonate) (P4HBS) was grown by slow evaporation solution technique (SEST) at room temperature. The lattice parameters of the grown crystal were confirmed by single crystal X-ray diffraction analysis. Functional groups of P4HBS crystal were confirmed by FTIR spectrum analysis. The optical quality of the grown crystal was identified by the UV-Vis NIR spectrum analysis. The grown crystal has good optical transmittance in the range of 410-1100 nm. In photoluminescence spectrum, sharp emission peaks are observed, which indicates the ultraviolet (UV) emission. The photoconductivity study reveals that the grown crystal has negative photoconductive nature. The thermal behaviour of the P4HBS crystal was investigated by thermogravimetric and differential thermal analysis (TG-DTA). The mechanical stability of grown crystal was analyzed and the indentation size effect (ISE) was explained by Hays-Kendall's (HK) approach and proportional specimen resistance model (PSRM). Chemical etching study was carried out and the etch pit density (EPD) was calculated. The dielectric constant (ε‧) and dielectric loss (tan δ) as a function of frequency were measured for the grown crystal. The solid state parameters such as valence electron, plasma energy, Penn gap and Fermi energy were evaluated theoretically for the P4HBS using the empirical relation. The estimated values are used to calculate the electronic polarizability. The third-order nonlinear optical properties such as nonlinear refractive index (n2), absorption co-efficient (β) and susceptibility (χ(3)) were studied by Z-scan technique at 632.8 nm using He-Ne laser.

  6. Synthesis, growth and characterization of a nonlinear optical crystal: Bis l-proline hydrogen nitrate.

    Science.gov (United States)

    Selvaraju, K; Kirubavathi, K

    2013-11-01

    The single crystals of bis l-proline hydrogen nitrate (BLPHN) belonging to non-centrosymmetric space group were successfully grown by the slow evaporation solution growth technique. The BLPHN crystals of size 10×7×3mm(3) were obtained in 35days. Initially, the solubility tests were carried out for two solvents such as deionized water and mixed of deionized water-acetone. Among the two solvents, the solubility of BLPHN was found to be the highest in deionized water, so crystallization of BLPHN was done from its aqueous solution. As grown, crystals were characterized by single crystal X-ray diffraction studies and optical transmission spectral studies. Infrared spectroscopy, thermo gravimetric analysis and differential thermal analysis measurements were performed to study the molecular vibration and thermal behavior of the grown BLPHN crystals. Nonlinear optical (NLO) behavior of BLPHN crystal was studied by Kurtz and Perry powder method. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Defect and surface asperity dependent yield during contact loading of an organic molecular single crystal

    Science.gov (United States)

    Ramos, K. J.; Bahr, D. F.; Hooks, D. E.

    2011-03-01

    The onset of plastic deformation was investigated using nanoindentation in single crystals of the explosive cyclotrimethylene trinitramine (RDX). Cleavage and habit planes were tested revealing a range of yielding behaviors. Smooth habit planes of unprocessed single crystals exhibited distinct yield points near the theoretical shear strength; planes produced by cleavage yielded at lower applied stresses. Cumulative probability distributions of maximum shear stresses at yield were used to illustrate the representative yielding behavior for samples prepared by the different methods. A statistically significant difference was observed for cleavage and habit planes. This suggested that structural defects, such as dislocations from growth and sample preparation, were being probed and nanoindentation can be used to correlate the mechanical response of organic molecular crystals with defect density. This capability may help explain the observed range of measurement differences in fundamental properties in this class of materials, such as sensitivity to the initiation of detonation in explosives, and disparate tablet integrity and stability responses in polymorphs of some pharmaceutical materials.

  8. Ultra-broadband nonlinear saturable absorption of high-yield MoS2 nanosheets.

    Science.gov (United States)

    Wei, Rongfei; Zhang, Hang; Hu, Zhongliang; Qiao, Tian; He, Xin; Guo, Qiangbing; Tian, Xiangling; Chen, Zhi; Qiu, Jianrong

    2016-07-29

    High-yield MoS2 nanosheets with strong nonlinear optical (NLO) responses in a broad near-infrared range were synthesized by a facile hydrothermal method. The observation of saturable absorption, which was excited by the light with photon energy smaller than the gap energy of MoS2, can be attributed to the enhancement of the hybridization between the Mo d-orbital and S p-orbital by the oxygen incorporation into MoS2. High-yield MoS2 nanosheets with high modulation depth and large saturable intensity generated a stable, passively Q-switched fiber laser pulse at 1.56 μm. The high output power of 1.08 mW can be attained under a very low pump power of 30.87 mW. Compared to recently reported passively Q-switched fiber lasers utilizing exfoliated MoS2 nanosheets, the efficiency of the laser for our passive Q-switching operation is larger and reaches 3.50%. This research may extend the understanding on the NLO properties of MoS2 and indicate the feasibility of the high-yield MoS2 nanosheets to passively Q-switched fiber laser effectively at low pump strengths.

  9. Nonlinear regime of the mode-coupling instability in 2D plasma crystals

    CERN Document Server

    Röcker, T B; Zhdanov, S K; Nosenko, V; Ivlev, A V; Thomas, H M; Morfill, G E

    2014-01-01

    The transition between linear and nonlinear regimes of the mode-coupling instability (MCI) operating in a monolayer plasma crystal is studied. The mode coupling is triggered at the centre of the crystal and a melting front is formed, which travels through the crystal. At the nonlinear stage, the mode coupling results in synchronisation of the particle motion and the kinetic temperature of the particles grows exponentially. After melting of the crystalline structure, the mean kinetic energy of the particles continued to grow further, preventing recrystallisation of the melted phase. The effect could not be reproduced in simulations employing a simple point-like wake model. This shows that at the nonlinear stage of the MCI a heating mechanism is working which was not considered so far.

  10. Modal theory of slow light enhanced third-order nonlinear effects in photonic crystal waveguides.

    Science.gov (United States)

    Chen, Tao; Sun, Junqiang; Li, Linsen

    2012-08-27

    In this paper, we derive the couple-mode equations for third-order nonlinear effects in photonic crystal waveguides by employing the modal theory. These nonlinear interactions include self-phase modulation, cross-phase modulation and degenerate four-wave mixing. The equations similar to that in nonlinear fiber optics could be expanded and applied for third-order nonlinear processes in other periodic waveguides. Based on the equations, we systematically analyze the group-velocity dispersion, optical propagation loss, effective interaction area, slow light enhanced factor and phase mismatch for a slow light engineered silicon photonic crystal waveguide. Considering the two-photon and free-carrier absorptions, the wavelength conversion efficiencies in two low-dispersion regions are numerically simulated by utilizing finite difference method. Finally, we investigate the influence of slow light enhanced multiple four-wave-mixing process on the conversion efficiency.

  11. Growth and characterization of new semiorganic nonlinear optical and piezoelectric lithium sulfate monohydrate oxalate single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Harsh [Crystal Lab, Department of Physics & Astrophysics, University of Delhi, Delhi 110007 (India); Sinha, Nidhi [Department of Physics & Electronics, SGTB Khalsa College, University of Delhi, Delhi 110007 (India); Kumar, Binay, E-mail: b3kumar69@yahoo.co.in [Crystal Lab, Department of Physics & Astrophysics, University of Delhi, Delhi 110007 (India)

    2015-04-15

    Highlights: • A new semiorganic single crystal of LSO grown by slow evaporation technique. • Morphological studies of the LSO crystal deduced by BFDH law. • In the UV–vis spectrum wide transparent region and large band gap were found. • SHG is equal to KDP crystal and d{sub 33} was found to be equal to 6pC/N. • Grown crystal belongs to softer category. - Abstract: New semiorganic crystal of lithium sulfate monohydrate oxalate (LSO) for nonlinear application was synthesized by controlled slow evaporation method. The growth rate of various planes of the grown crystal was estimated by morphological study. Single crystal XRD analysis confirmed that the crystal belongs to triclinic lattice with space group P1. High transparency (∼95%) with large band gap (4.57 eV) was analyzed by UV–vis studies. FTIR and Raman spectroscopy were used to identify various functional groups present in the LSO crystal. SHG efficiency was found to be equal to the KDP crystal. Thermal stability (up to 117.54 °C) and melting point (242 °C) of the crystal were studied by TG-DTA. In dielectric measurements, the value of dielectric constant decreases with increase in frequency. Hardness studies confirmed soft nature of crystals. The piezoelectric coefficient was found to be 6pC/N along [0 0 1].

  12. Slow light enhanced optical nonlinearity in a silicon photonic crystal coupled-resonator optical waveguide.

    Science.gov (United States)

    Matsuda, Nobuyuki; Kato, Takumi; Harada, Ken-Ichi; Takesue, Hiroki; Kuramochi, Eiichi; Taniyama, Hideaki; Notomi, Masaya

    2011-10-10

    We demonstrate highly enhanced optical nonlinearity in a coupled-resonator optical waveguide (CROW) in a four-wave mixing experiment. Using a CROW consisting of 200 coupled resonators based on width-modulated photonic crystal nanocavities in a line defect, we obtained an effective nonlinear constant exceeding 10,000 /W/m, thanks to slow light propagation combined with a strong spatial confinement of light achieved by the wavelength-sized cavities.

  13. Initial dynamics of supercontinuum generation in highly nonlinear photonic crystal fiber.

    Science.gov (United States)

    Moeser, J T; Wolchover, N A; Knight, J C; Omenetto, F G

    2007-04-15

    We present a theoretical and experimental analysis of supercontinuum generation in very short lengths of high-nonlinearity photonic crystal fibers. The Raman response function for Schott SF6 glass is presented for what is believed to be the first time and used for numerical modeling of pulse propagation. Simulation and experiments are in excellent agreement and demonstrate the rapid transition to regimes of spectral complexity due to higher-order nonlinear effects.

  14. Cavity optomechanics with a nonlinear photonic-crystal nanomembrane

    Energy Technology Data Exchange (ETDEWEB)

    Makles, Kevin; Kuhn, Aurélien; Briant, Tristan; Cohadon, Pierre-François; Heidmann, Antoine [Laboratoire Kastler Brossel, UPMC-ENS-CNRS, Case 74, 4 place Jussieu, F75252 Paris Cedex 05 (France); Antoni, Thomas [Laboratoire de Photonique et Nanostructures LPN-CNRS, UPR-20, Route de Nozay, 91460 Marcoussis, France and Laboratoire Kastler Brossel, UPMC-ENS-CNRS, Case 74, 4 place Jussieu, F75252 Paris Cedex 05 (France); Braive, Rémy [Laboratoire de Photonique et Nanostructures LPN-CNRS, UPR-20, Route de Nozay, 91460 Marcoussis, France and Université Paris Diderot, 10, rue Alice Domon et Léonie Duquet, 75205 Paris, Cedex 13 (France); Sagnes, Isabelle; Robert-Philip, Isabelle [Laboratoire de Photonique et Nanostructures LPN-CNRS, UPR-20, Route de Nozay, 91460 Marcoussis (France)

    2014-12-04

    We have designed, fabricated and characterized a nanomembrane which could be used as a moving end mirror of a Fabry-Perot cavity. The high reflectivity and optimized mechanical properties of the membrane should allow us to demonstrate the mechanical ground state of the membrane. As any sub-micron mechanical resonator, our system demonstrates nonlinear dynamical effects. We characterize the mechanical response to a strong pump drive and observe a shift in the oscillation frequency and phase conjugation of the mechanical mode. Such nonlinear effects are expected to play a role in the quantum dynamics of the membrane as well.

  15. Nonlinear processes upon two-photon interband picosecond excitation of PbWO4 crystal

    Science.gov (United States)

    Lukanin, V. I.; Karasik, A. Ya

    2016-09-01

    A new experimental method is proposed to study the dynamics of nonlinear processes occurring upon two-photon interband picosecond excitation of a lead tungstate crystal and upon its excitation by cw probe radiation in a temporal range from several nanoseconds to several seconds. The method is applied to the case of crystal excitation by a sequence of 25 high-power picosecond pulses with a wavelength of 523.5 nm and 633-nm cw probe radiation. Measuring the probe beam transmittance during crystal excitation, one can investigate the influence of two-photon interband absorption and the thermal nonlinearity of the refractive index on the dynamics of nonlinear processes in a wide range of times (from several nanoseconds to several seconds). The time resolution of the measuring system makes it possible to distinguish fast and slow nonlinear processes of electronic or thermal nature, including the generation of a thermal lens and thermal diffusion. An alternative method is proposed to study the dynamics of induced absorption transformation and, therefore, the dynamics of the development of nonlinear rocesses upon degenerate two-photon excitation of the crystal in the absence of external probe radiation.

  16. Self-induced transparency and giant nonlinearity in doped photonic crystals

    CERN Document Server

    Kurizki, G; Opatrny, T; Blaauboer, M; Malomed, B; Kurizki, Gershon; Petrosyan, David; Opatrny, Tomas; Blaauboer, Miriam; Malomed, Boris

    2002-01-01

    Photonic crystals doped with resonant atoms allow for uniquely advantageous nonlinear modes of optical propagation: (a) Self-induced transparency (SIT) solitons and multi-dimensional localized "bullets" propagating at photonic band gap frequencies. These modes can exist even at ultraweak intensities (few photons) and therefore differ substantially either from solitons in Kerr-nonlinear photonic crystals or from SIT solitons in uniform media. (b) Cross-coupling between pulses exhibiting electromagnetically induced transparency (EIT) and SIT gap solitons. We show that extremely strong correlations (giant cross-phase modulation) can be formed between the two pulses. These features may find applications in high-fidelity classical and quantum optical communications.

  17. Intracavity frequency doubling of CW Ti:Sapphire laser utilising BiBO nonlinear crystal

    DEFF Research Database (Denmark)

    Thorhauge, Morten; Mortensen, Jesper Liltorp; Tidemand-Lichtenberg, Peter

    Utilising BiBO nonlinear crystal frequency doubling a Ti:Sapphire CW laser gave 100 mW at 405 nm and 53 mW at 392 nm. Stability proved excellent without servo control. Broad tunability was shown around 392 nm.......Utilising BiBO nonlinear crystal frequency doubling a Ti:Sapphire CW laser gave 100 mW at 405 nm and 53 mW at 392 nm. Stability proved excellent without servo control. Broad tunability was shown around 392 nm....

  18. Research on Nonlinear Absorption Effect in KDP and 70%-DKDP Crystals

    Directory of Open Access Journals (Sweden)

    Duanliang Wang

    2017-07-01

    Full Text Available Nonlinear optical absorption effect in KDP and 70%-DKDP crystals, which were grown by the conventional temperature cooling method, was systematically studied using picosecond pulse laser excitation. Using open aperture Z-scan measurements, the dependence of nonlinear absorption effect on sample orientations (I, II, and z as well as laser intensity was systematically measured at λ = 1064 and 532 nm. According to the experimental results, the nonlinear absorption effect at λ = 532 nm was confirmed, while at λ = 1064 nm no nonlinear absorption was observed for KDP and 70%-DKDP crystals. In addition, the optical absorption along I- and II-type affected by laser intensity was larger than that along the z-direction. The important nonlinear absorption coefficients β and χ I ( 3 (esu measured along different orientations were exhibited in detail at wavelengths of 1064 nm and 532 nm. The results indicate that nonlinear absorption coefficients increase first and then decrease with the increment of laser intensity for KDP and 70%-DKDP crystals.

  19. Frequency conversion, nonlinear absorption and carrier dynamics of GaSe:B/Er crystals

    Science.gov (United States)

    Yuksek, Mustafa; Karatay, Ahmet; Ertap, Hüseyin; Elmali, Ayhan; Karabulut, Mevlut

    2017-04-01

    We aimed to investigate the influence of Er3+ rare earth element on the frequency conversion wavelength in boron doped GaSe crystals. It was found that by substitution of Er3+ with B3+, SHG signal shifted to higher wavelength. In addition, the nonlinear absorption properties and ultrafast dynamics of pure, 0.5 at% B3+ and 0.25 at% B3+ + 0.25 at% Er3+ doped GaSe crystals have been studied by open aperture Z-scan and ultrafast pump probe spectroscopy techniques. All of the studied crystals showed nonlinear absorption (NA). It was observed that 0.5 at% B3+ doped GaSe crystal showed bleach signal. This signal switched to NA signal with long life after substitution of 0.25 at% Er3+ with 0.25 at% B3+.

  20. Properties of a New Nonlinear Optical Crystal CdZn2B2O6

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fan; SHEN De-Zhong; SHEN Guang-Qiu; WANG Xiao-Qing

    2008-01-01

    @@ Cadmium dizinc diborate (CdZn2B2O6) single crystals have been grown for the first time. The crystal structure of CdZn2B2O6 is the same as that of the Cd3Zn3B4O12. The x-ray diffraction, infrated and Raman spectra,differential scanning calorimetry analysis and density indicate that the physical and chemical properties of both crystals are very similar. Especially, the nonlinear optical coefficients of CdZn2B2O6 and Cd3ZnaB4O12 crystals are 2.6 and 2.4 times as large as that of KH2PO4 crystal respectively. Chemical etching experiments indicated that these crystals are very stable in neutral solution and not hygroscopic in air at room temperature.

  1. Generation of 3.5 W of diffraction-limited green light from SHG of a single tapered diode laser in a cascade of nonlinear crystals

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Jensen, Ole Bjarlin; Sumpf, Bernd

    2014-01-01

    -focusing and dispersion compensating optics between the two nonlinear crystals. In the low-power limit, such a cascade of two crystals has the theoretical potential for generation of four times as much power as a single crystal without adding significantly to the complexity of the system. The experimentally achieved...... frequency conversion of infrared tapered diode lasers. Here, we describe the generation of 3.5 W of diffraction-limited green light from SHG of a single tapered diode laser, itself yielding 10 W at 1063 nm. This SHG is performed in single pass through a cascade of two PPMgO:LN crystals with re...... power of 3.5 W corresponds to a power enhancement greater than 2 compared to SHG in each of the crystals individually and is the highest visible output power generated by frequency conversion of a single diode laser. Such laser sources provide the necessary pump power for biophotonics applications...

  2. Nonlinear optical properties of polymer dispersed liquid crystals doped with La2CaB10019

    Science.gov (United States)

    Zegadlo, Krzysztof B.; El Ouazzani, Hasnaa; Cieslik, Iwona; Weglowski, Rafal; Zmija, Jozef; Klosowicz, Stanislaw; Majchrowski, Andrzej; Mysliwiec, Jaroslaw; Sahraoui, Bouchta; Karpierz, Miroslaw A.

    2012-08-01

    Second order nonlinearity in polymer dispersed liquid crystal structures containing La2CaB10O19 nanocrystals were measured with use of the Maker fringes method. The composites with different concentration of La2CaB10O19 crystallites or without them were compared. It was shown that there is a strong influence of the crystals concentration on the second harmonic generation in such structures which can be additionally modified by external electric field.

  3. Parameters for efficient growth of second harmonic field in nonlinear photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Shereena, E-mail: sherin5462@gmail.com; Khan, Mohd. Shahid; Hafiz, Aurangzeb Khurram

    2014-03-01

    The ultrashort pulse propagation and nonlinear second harmonic generation under the undepleted pump approximation in a quadratic nonlinear photonic crystal (NPC) structure is theoretically investigated and the optimized parameters for high second harmonic generation conversion efficiency are extracted. The transfer matrix method is used for the numerical formulation for oblique angle of incidence. A unique set of material combination GaInP/InAlP is selected as alternating nonlinear and linear layers. The NPC parameters like incident angle and layer thickness are manipulated to obtain the exact phase matching using double resonance condition for a fixed number of layers with known experimental material parameters.

  4. Theory of director precession and nonlinear waves in nematic liquid crystals under elliptical shear.

    Science.gov (United States)

    Krekhov, A P; Kramer, L

    2005-09-01

    We study theoretically the slow director precession and nonlinear waves observed in homeotropically oriented nematic liquid crystals subjected to circular or elliptical Couette and Poiseuille flow and an electric field. From a linear analysis of the nematodynamic equations it is found that in the presence of the flow the electric bend Fréedericksz transition is transformed into a Hopf-type bifurcation. In the framework of an approximate weakly nonlinear analysis we have calculated the coefficients of the modified complex Ginzburg-Landau equation, which slightly above onset describes nonlinear waves with strong nonlinear dispersion. We also derive the equation describing the precession and waves well above the Fréedericksz transition and for small flow amplitudes. Then the nonlinear waves are of diffusive nature. The results are compared with full numerical simulations and with experimental data.

  5. Switching behaviour of nonlinear Mach–Zehnder interferometer based on photonic crystal geometry

    Indian Academy of Sciences (India)

    Man Mohan Gupta; S Medhekar

    2014-06-01

    Nonlinear Mach–Zehnder interferometer (NMZI) created with photonic crystal waveguides (PCW) and with Kerr-type nonlinearity has been investigated in this paper. The NMZI has been simulated using two-dimensional finite difference time domain (2D-FDTD) method. Input verses output (I/O) characteristics have been obtained for different lengths of the nonlinear arm, nonlinear coefficients of the nonlinear arm, wavelengths of the input beam, sizes of defect rods and NMZI offset. The results obtained are compared with earlier published results of NMZI created with conventional step index waveguides (SIW). It is shown that all useful features of light switching offered by SIW-based NMZIs are also possible with PCW-based NMZIs of extremely small dimensions. Moreover, PCW-based NMZIs offer additional useful feature not available with SIW-based NMZIs.

  6. Soliton Properties of Light Pulses on the Surface of Ionic Crystals Generated by Strong Nonlinear Effects

    Institute of Scientific and Technical Information of China (English)

    NIU Jia-Sheng; MA Ben-Kun

    2003-01-01

    In this paper, we theoretically discuss the soliton properties of light pulse transportation on the surface of an ionic crystal having strong nonlinear interactions between ions of unit cells. We analyze in detail the dark solitons when the nonlinear coefficient g is positive and negative, respectively. It is found that whether the nonlinear coefficient g is positive or negative, the dark solitons can be formed over the whole dispersion relation area of surface polaritons considering nonlinear effects. Attention should be paid to the fact that around ωTO, the light pulse can form advanced dark solitons, and there is a switching area from advanced dark soliton to retarded dark soliton near ωTO. We also discuss the effects of higher nonlinear dispersion on the solitons.

  7. A review of recent theoretical studies in nonlinear crystals: towards the design of new materials

    Science.gov (United States)

    Luppi, Eleonora; Véniard, Valérie

    2016-12-01

    Nonlinear optics is an important and exciting field of fundamental and applied research, with applications in many different disciplines such as physics chemistry, material science and biology. In the recent years, nonlinear optical phenomena started to be also widely used in technological applications for optoelectronics and photovoltaics. This coincided with an important experimental and theoretical search for new materials with an efficient and exploitable nonlinear optical response. Here, starting from the discovery of nonlinear optics, we review the most important theoretical formalisms developed to understand, interpret and predict the nonlinear optical phenomena. We show the different level of approximation of the many-electrons interactions that these formalisms can describe which are fundamental in the interpretation of the experiments. The impact of the theory is then analyzed on different classes of new materials particularly studied in these years: silicon bulk to nano, compound semiconductors, graphene, transition metal dichalcogenide, hexagonal boron nitride and borate crystals.

  8. Growth and characterization of butyl 4-hydroxybenzoate single crystal by vertical Bridgman technique for third order nonlinear optical applications

    Science.gov (United States)

    Arivazhagan, T.; Siva Bala Solanki, S.; Rajesh, Narayana Perumal

    2017-02-01

    The butyl 4-hydroxybenzoate single crystal has been grown by vertical Bridgman technique using single wall ampoule. The cell parameters of the grown crystal are verified by single crystal X-ray diffraction analysis. The functional groups of the grown crystal were identified by Fourier transform infrared analysis. The melting, decomposition and crystallization point of the compound are determined by thermo gravimetric analysis and differential scanning calorimetric analysis. The mechanical properties of the grown crystal has been analyzed by Vickers microhardness method. The optical behavior of the grown crystal has been observed by UV-vis-NIR transmission spectroscopic analysis which shows that the lower cut-off wavelength lying at 293 nm and found that the energy band gap value is 4.05 eV. The blue light emission of the crystal was identified by photoluminescence studies. The positive third order nonlinear optical parameters like nonlinear refractive index (n2), nonlinear absorption co-efficient (β) and third order nonlinear susceptibility (χ3) of the grown crystal was calculated by Z-scan studies. The positive sign of nonlinear refractive index (n2) indicates that the crystal exhibits self focusing optical nonlinearity. The crystal exhibits good optical power limiting behavior.

  9. Crystal growth and properties of novel organic nonlinear optical crystals of 4-Nitrophenol urea

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, M. Krishna, E-mail: krishnamohan.m@ktr.srmuniv.ac.in; Ponnusamy, S.; Muthamizhchelvan, C.

    2017-07-01

    Single crystals of 4-Nitrophenol urea have been grown from water using slow evaporation technique at constant temperature, with the vision to improve the properties of the crystals. The unit cell parameters of the grown crystals were determined by single crystal and powder X-Ray diffraction. FTIR studies reveals the presence of different vibrational bands. The Optical studies confirmed that the crystal is transparent up to 360 nm .TGA and DSC studies were carried out to understand the thermal behavior of crystals. The SHG studies show the suitability of the crystals for NLO applications. The etching studies were carried out to study the behavior of the crystals under different conditions.These studies reveal that the crystals of 4-Nitrophenol urea are suitable for device applications. - Highlights: • 4-Nitrophenol urea crystals of dimensions 14 mm × 1 mm were grown. • UV–Visible studies indicate the crystal is transparent in the region of 370–800 nm. • Thermal studies show the crystal starts decomposing at 170 °C. • SHG studies indicate that the crystals have NLO efficiency 3.5 times that of KDP.

  10. Development of Chalcopyrite Crystals for Nonlinear Optical Applications

    Science.gov (United States)

    1974-12-01

    write the expansion ol the homopolar and the heteropolar part of the mean energy gap in the following way. £.(«) - £. + (a«», + (a.)’*, + (Ha) C...a nearly linear relation over a wide 7 —12-um spectral range. We therefore used a 1 stepping motor and synchronously rotated the AgGaSe, crystal

  11. Optimizing nonlinear beam coupling in low-symmetry crystals.

    Science.gov (United States)

    Shumelyuk, A; Volkov, A; Odoulov, S; Grabar, A; Stoyka, I; Evans, D R

    2014-10-01

    The purpose of this paper is to find the polarizations and spatial orientations of the two interacting counterpropagating coherent light waves which ensure the largest beam coupling in monoclinic photorefractive crystal. The results of calculations are presented that are verified experimentally with Sn₂P₂S₆.

  12. Nonlinear spatial mode imaging of hybrid photonic crystal fibers

    DEFF Research Database (Denmark)

    Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Laurila, Marko;

    2013-01-01

    Degenerate spontaneous four wave mixing is studied for the rst time in a large mode area hybrid photonic crystal ber, where light con nement is achieved by combined index- and bandgap guiding. Four wave mixing products are generated on the edges of the bandgaps, which is veri ed by numerical...

  13. Cathodoluminescence Study of Orientation-Patterned GaAs Crystals for Nonlinear Optics

    Science.gov (United States)

    Martínez, O.; Avella, M.; Hortelano, V.; Jiménez, J.; Lynch, C.; Bliss, D.

    2010-06-01

    Orientation-patterned (OP) GaAs crystals are very promising for their use in nonlinear optical applications. In particular, mid-infrared and terahertz lasers can be generated by frequency conversion from shorter-wavelength sources. However, the quality of the crystals is crucial for high conversion efficiency, as the presence of defects with electrooptical signatures can contribute to optical losses. The study of these defects is a step toward the improvement of OP-GaAs crystals. We present here a spectroscopic cathodoluminescence study of the distribution of the main defects. Tentative relations between defects and the optical propagation losses are discussed.

  14. Thermal and Transmission Properties of UV Nonlinear Optical Material-- ZnCd(SCN)4 Crystal

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Zinc cadmium thiocyanate(ZCTC), ZnCd(SCN)4, has been discovered as a UV second-order nonlinear optical coordination crystal. Its thermal and transmission properties are reported. The thermal decomposition is characterized by using the X-ray powder diffraction (XRPD) and infrared (IR) spectroscopy at room temperature. The absorptions of intrinsic ions and ZCTC in a solution state are discussed as well as transmission properties of the ZCTC crystal. An effective method of reducing the surface reflection loss of ZCTC crystal is introduced.

  15. Growth and characterization of L-valine - a nonlinear optical crystal

    Energy Technology Data Exchange (ETDEWEB)

    Moitra, S.; Kar, T. [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India)

    2010-01-15

    The growth of a new nonlinear optical material L-valine by solvent evaporation method is reported here. To grow good quality crystals pH value of growth solution has been optimized and solubility of L-valine in different solvents and different pH values was determined. The grown crystals were characterized by IR, single crystal XRD, DTA and TGA, optical transmission and second harmonic generation (SHG) efficiency measurement. SHG efficiency of L-valine was found equivalent to KDP and its transmission is 75%-80% from ultraviolet to near IR region. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. Unidirectional growth, rocking curve, linear and nonlinear optical properties of LPHCl single crystals

    Science.gov (United States)

    Kumar, P. Ramesh; Gunaseelan, R.; Raj, A. Antony; Selvakumar, S.; Sagayaraj, P.

    2012-06-01

    Nonlinear optical amino-acid single crystal of L-phenylalanine hydrochloride (LPHCl) was successfully grown by unidirectional Sankaranarayanan-Ramasamy (SR) method under ambient conditions for the first time. The grown single crystal was subjected to different characterization analyses in order to find out its suitability for device fabrication. The crystalline perfection was evaluated using high-resolution X-ray diffractometry. It is evident from the optical absorption study that crystal has excellent transmission in the entire visible region with its lower cut off wavelength around 290 nm.

  17. Dynamic yield and tensile strength of aluminum single crystals at temperatures up to the melting point

    Energy Technology Data Exchange (ETDEWEB)

    Kanel, G. I.; Razorenov, S. V.; Baumung, K.; Singer, J.

    2001-07-01

    This article presents experimental results of the dynamic yield strength and dynamic tensile strength ({open_quotes}spall strength{close_quotes}) of aluminum single crystals at shock-wave loading as a function of temperature. The load duration was {similar_to}40 and {similar_to}200 ns. The temperature varied from 20 to 650{degree}C which is only by 10{degree}C below the melting temperature. A linear growth of the dynamic yield strength by more than a factor of 4 was observed within this temperature range. This is attributed to the phonon drag effect on the dislocation motion. High dynamic tensile strength was maintained over the whole temperature range, including the conditions at which melting should start in a material under tension. This could be an indication of the existence of superheated states in solid crystals. {copyright} 2001 American Institute of Physics.

  18. Experimental demonstration of non-reciprocal transmission in a nonlinear photonic-crystal Fano structure

    DEFF Research Database (Denmark)

    Yu, Yi; Chen, Yaohui; Hu, Hao;

    2015-01-01

    We suggest and experimentally demonstrate a photonic-crystal structure with more than 30 dB difference between forward and backward transmission levels. The non-reciprocity relies on the combination of ultrafast carrier nonlinearities and spatial symmetry breaking in a Fano structure employing...

  19. High intensity polarization entangled source with a 2D nonlinear photonic crystal

    DEFF Research Database (Denmark)

    Wang, Qin

    2009-01-01

    We gave a proposal on how to use a piece of two-dimension (2D) nonlinear photonic crystal to generate a polarization entangled source. It provides not only has a high stability, but also a high entangled quality and a high intensity. Moreover, our scheme involves only practical experimental...

  20. Nonlinear Control of Absorption in Graphene-based 1D Photonic Crystal

    CERN Document Server

    Vincenti, M A; Grande, M; D'Orazio, A; Scalora, M

    2013-01-01

    Perfect, narrow-band absorption is achieved in an asymmetric 1D photonic crystal with a monolayer graphene defect. Thanks to the large third order nonlinearity of graphene and field localization in the defect layer we demonstrate the possibility to achieve controllable, saturable absorption for the pump frequency.

  1. Cascading nonlinearities in an organic single crystal core fiber: The Cerenkov regime

    NARCIS (Netherlands)

    Torruellas, William E.; Krijnen, Gijs; Kim, Dug Y.; Schiek, Roland; Stegeman, George J.; Vidakovic, Petar; Zyss, Joseph

    1994-01-01

    The large nonlinear phase shifts imparted to the fundamental beam during Cerenkov second harmonic generation (SHG) in a DAN, 4-(N,N-dimethylamino)-3-acetamidonitrobenzene, single crystal core fiber are explained and modelled numerically. Cascading upconversion and downconversion processes leads to n

  2. Features of plastic strain localization at the yield plateau in Hadfield steel single crystals

    Science.gov (United States)

    Barannikova, S. A.; Zuev, L. B.

    2008-07-01

    Spatiotemporal distributions of local components of the plastic distortion tensor in Hadfield steel single crystals oriented for single twinning have been studied under active tensile straining conditions using the double-exposure speckle photography technique. Features of the macroscopically inhomogeneous strain localization at the yield plateau are considered. Relations between local components of the plastic distortion tensor in the zone of strain localization are analyzed.

  3. Synthesis, growth and characterization of a nonlinear optical crystal: l-Leucinium perchlorate

    Directory of Open Access Journals (Sweden)

    P. Baskaran

    2017-01-01

    Full Text Available An amino acid based semiorganic nonlinear optical family single crystal of l-leucinium perchlorate (LLPCl was grown by the solvent evaporation method at ambient temperature. Good optical quality single crystals up to a size of 6 mm × 5 mm × 3 mm were obtained. The single-crystal XRD analysis shows that the grown crystals have a monoclinic structure. Fourier transform infrared (FTIR spectral analysis and UV–vis spectral studies were also carried out. Microhardness mechanical studies show that the hardness number (Hv of a LLPCl single crystal decreases with the load as measured by the Vickers microhardness method. The dielectric properties of the grown crystal were analysed by varying the frequency. Photoconductivity analysis gives the variation of the photocurrent and dark current. The nonlinear optical properties were studied using the Kurtz and Perry powder method and the second harmonic generation efficiency was found to be 2.6 times higher than that of KDP crystals.

  4. Design of an efficient terahertz source using triply resonant nonlinear photonic crystal cavities.

    Science.gov (United States)

    Burgess, Ian B; Zhang, Yinan; McCutcheon, Murray W; Rodriguez, Alejandro W; Bravo-Abad, Jorge; Johnson, Steven G; Loncar, Marko

    2009-10-26

    We propose a scheme for efficient cavity-enhanced nonlinear THz generation via difference-frequency generation (DFG) processes using a triply resonant system based on photonic crystal cavities. We show that high nonlinear overlap can be achieved by coupling a THz cavity to a doubly-resonant, dual-polarization near-infrared (e.g. telecom band) photonic-crystal nanobeam cavity, allowing the mixing of three mutually orthogonal fundamental cavity modes through a chi((2)) nonlinearity. We demonstrate through coupled-mode theory that complete depletion of the pump frequency - i.e., quantum-limited conversion - is possible. We show that the output power at the point of optimal total conversion efficiency is adjustable by varying the mode quality (Q) factors.

  5. Tuning quadratic nonlinear photonic crystal fibers for zero group-velocity mismatch

    DEFF Research Database (Denmark)

    Bache, Morten; Nielsen, Hanne; Lægsgaard, Jesper;

    2006-01-01

    We consider an index-guiding silica photonic crystal fiber with a triangular hole pattern and a periodically poled quadratic nonlinearity. By tuning the pitch and the relative hole size, second-harmonic generation with zero group-velocity mismatch is found for any fundamental wavelength above 780...... nm. The nonlinear strength is optimized when the fundamental has maximum confinement in the core. The conversion bandwidth allows for femtosecond-pulse conversion, and 4%-180% W-1 cm-2 relative efficiencies were found. © 2006 Optical Society of America......We consider an index-guiding silica photonic crystal fiber with a triangular hole pattern and a periodically poled quadratic nonlinearity. By tuning the pitch and the relative hole size, second-harmonic generation with zero group-velocity mismatch is found for any fundamental wavelength above 780...

  6. Soliton compression to ultra-short pulses using cascaded quadratic nonlinearities in silica photonic crystal fibers

    DEFF Research Database (Denmark)

    Bache, Morten; Lægsgaard, Jesper; Bang, Ole;

    2007-01-01

    We investigate the possibility of using poled silica photonic crystal fibers for self-defocusing soliton compression with cascaded quadratic nonlinearities. Such a configuration has promise due to the desirable possibility of reducing the group-velocity mismatch. However, this unfortunately leads...... nonlinearity, and show that compression of nJ pulses to few-cycle duration is possible in such a fiber. A small amount of group-velocity mismatch optimizes the compression.......We investigate the possibility of using poled silica photonic crystal fibers for self-defocusing soliton compression with cascaded quadratic nonlinearities. Such a configuration has promise due to the desirable possibility of reducing the group-velocity mismatch. However, this unfortunately leads...

  7. Growth, dielectric and nonlinear optical properties of Li3Cs2B5O10 single crystals

    Science.gov (United States)

    Sukumar, M.; Ramesh Babu, R.; Ramamurthi, K.

    2017-01-01

    Lithium cesium borate (Li3Cs2B5O10), an alkali metal borate, single crystals were grown by Czochralski method. Chemical etching was performed on grown Li3Cs2B5O10 crystal at various regions. The observed dislocation densities are varied at different regions of the grown Li3Cs2B5O10 crystal. Dielectric behavior of Li3Cs2B5O10 crystal at different temperatures is studied. The third-order nonlinear optical parameters of lithium cesium borate crystal are determined by Z-scan technique. The nonlinear refractive index ( n 2) value is estimated to be -7.272 × 10-11 cm2/W, and the corresponding third-order nonlinear susceptibility ( χ 3) is estimated to be 4.19 × 10-9 esu. The measured nonlinear refractive indices reveal the self-defocusing effect of Li3Cs2B5O10 crystal.

  8. Microhardness studies on nonlinear optical -alanine single crystals

    Indian Academy of Sciences (India)

    R Hanumantharao; S Kalainathan

    2013-06-01

    Vickers and Knoop microhardness tests were carried out on grown -alanine single crystals by slow evaporation technique over a load range of 10–50 g on selected broad (2 0 3) plane. Vickers (v) and Knoop (k) microhardness for the above loads were found to be in the range of 60–71 kg/mm2 and 35–47 kg/mm2, respectively. Vickers microhardness number (v) and Knoop microhardness number (k) were found to increase with increasing load. Meyer’s index number () calculated from v shows that the material belongs to the soft material category. Using Wooster’s empirical relation, the elastic stiffness constant (11) was calculated from Vickers hardness values. Young’s modulus was calculated using Knoop hardness values. Hardness anisotropy has been observed in accordance with the orientation of the crystal.

  9. Growth and characterization of Cadmium Thiosemicarbazide Bromide crystals for antibacterial and nonlinear optical applications

    Science.gov (United States)

    Thomas Joseph Prakash, J.; Martin Sam Gnanaraj, J.

    2015-01-01

    Semiorganic nonlinear optical crystals of Cadmium Thiosemicarbazide Bromide was grown by slow evaporation solution growth technique. The unit cell parameters were estimated by subjecting the crystals to single crystal X-ray diffraction. The grown crystals were subjected to Powder X-ray diffraction for analyzing the crystalline nature of the sample. FTIR studies reveal the functional groups and the optical characters were analyzed by UV-Vis spectral studies. Mechanical stability of the sample was assessed by Vicker's micro hardness test. The presence of surface dislocations was identified by chemical etching technique. Antibacterial study was carried out against ACDP declared harmful pathogens. SHG efficiency of CTSB crystal was tested using Nd: YAG laser and it was found to be ∼1.8 times that of potassium dihydrogen phosphate.

  10. Cascaded third-harmonic generation in a single short-range-ordered nonlinear photonic crystal.

    Science.gov (United States)

    Sheng, Yan; Saltiel, Solomon M; Koynov, Kaloian

    2009-03-01

    Collinear third-harmonic generation at 526.7 nm was realized by the simultaneous phase matching of two second-order processes in a single quadratic crystal: second-harmonic generation (SHG) and sum-frequency mixing (SFM). The measured conversion efficiency was 12%. As a nonlinear medium a LiNbO(3) nonlinear photonic crystal with short-range order was used that allowed simultaneous phase matching by use of discrete reciprocal vector (for the SHG process) and continuous reciprocal vectors (for the SFM process). It was demonstrated that the third harmonic could be generated efficiently in such a crystal even if the intermediate process of SHG was not perfectly phase matched.

  11. Vibrational and third-order nonlinear optical study on hydroxyethylammonium picrate (HEAP) single crystals

    Science.gov (United States)

    Sudharsana, N.; Nagalakshmi, R.; Krishnakumar, V.; Sharma, A.; Fausto, R.; Row, T. N. Guru; Pal, Rumpa

    2012-06-01

    Single crystals of hydroxyethylammonium picrate (C8 H10N4O8; HEAP) have been grown for the first time by slow evaporation solution growth technique at room temperature, using ethanol as solvent. FT-IR and Raman spectra were recorded for HEAP at room temperature. The main vibrational bands related to NH3+ and CO- (picrate) groups, involved in charge transfer, are discussed. Second-order hyperpolarizability(γ) for the single crystal was evaluated theoretically to be 3.48×10-28 e.s.u. A Z-scan study of HEAP showed that the relative third-order nonlinear refractive index is -9.2×10-5cm2/W. The measured third-order nonlinear properties confirm the suitability of the crystal for optical limiting and switching applications.

  12. Crystal growth and characterization of new semiorganic nonlinear optical single crystals

    Science.gov (United States)

    Kulshrestha, Shobha; Shrivastava, A. K.

    2016-05-01

    An organic material of a L-histidine monohydrochloride single crystal was grown in a distilled water solution using the slow evaporation method at 40-45°C. The grown crystal was transparent and colourless, with a size of about 20 × 9 × 5 mm3, obtained within a period of 21 days. The solubility of grown crystals have found out at various temperatures. The UV-visible transmittance studies show that the grown crystals have wide optical transparency in the entire visible region It is observed that the crystal has transparency window from 255nm to 700nm and its energy gap (Eg) found to be is 3.1eV. The grown crystal was subjected to powder X-ray diffraction analysis, confirming that the orthorhombic crystalline nature of the crystal. To identify the surface morphology, the as grown crystal was subjected to FE-SEM technique. The chemical composition of the grown crystal was estimated by Energy dispersive X-ray analysis. The optical behaviour of the grown crystal was analyzed by PL study.

  13. Synthesis, crystal structure, growth, optical and third order nonlinear optical studies of 8HQ2C5N single crystal - An efficient third-order nonlinear optical material

    Energy Technology Data Exchange (ETDEWEB)

    Divya Bharathi, M.; Ahila, G.; Mohana, J. [Department of Physics, Presidency College, Chennai 600005 (India); Chakkaravarthi, G. [Department of Physics, CPCL Polytechnic College, Chennai 600068 (India); Anbalagan, G., E-mail: anbu24663@yahoo.co.in [Department of Nuclear Physics, University of Madras, Chennai 600025 (India)

    2017-05-01

    A neoteric organic third order nonlinear optical material 8-hydroxyquinolinium 2-chloro-5-nitrobenzoate dihydrate (8HQ2C5N) was grown by slow cooling technique using ethanol: water (1:1) mixed solvent. The calculated low value of average etch pit solidity (4.12 × 10{sup 3} cm{sup −2}) indicated that the title crystal contain less defects. From the single crystal X-ray diffraction data, it was endowed that 8HQ2C5N crystal belongs to the monoclinic system with centrosymmetric space group P2{sub 1}/c and the cell parameters values, a = 9.6546 (4) Ǻ, b = 7.1637(3) Ǻ, c = 24.3606 (12) Ǻ, α = γ = 90°, β = 92.458(2)° and volume = 1683.29(13) Ǻ{sup 3}. The FT-IR and FT-Raman spectrum were used to affirm the functional group of the title compound. The chemical structure of 8HQ2C5N was scrutinized by {sup 13}C and {sup 1}H NMR spectral analysis and thermal stability through the differential scanning calorimetry study. Using optical studies the lower cut-off wavelength and optical band gap of 8HQ2C5N were found to be 364 nm and 3.17 eV respectively. Using the single oscillator model suggested by Wemple – Didomenico, the oscillator energy (E{sub o}), the dispersion energy (E{sub d}) and static dielectric constant (ε{sub o}) were estimated. The third-order susceptibility were determined as Im χ{sup (3)} = 2.51 × 10{sup −5} esu and Re χ{sup (3)} = 4.46 × 10{sup −7} esu. The theoretical third-order nonlinear optical susceptibility χ{sup (3)} was calculated and the results were compared with experimental value. Photoluminescence spectrum of 8HQ2C5N crystal showed the yellow emission. The crystal had the single shot laser damage threshold of 5.562 GW/cm{sup 2}. Microhardness measurement showed that 8HQ2C5N belongs to a soft material category. - Highlights: • A new organic single crystals were grown and the crystal structure was reported. • Crystal possess, good transmittance, thermal and mechanical stability. • Single shot LDT value is found to be

  14. The anisotropic Kerr nonlinear refractive index of the beta-barium borate (β-BaB2O4) nonlinear crystal

    DEFF Research Database (Denmark)

    Bache, Morten; Guo, Hairun; Zhou, Binbin

    2013-01-01

    We study the anisotropic nature of the Kerr nonlinear response in a beta-barium borate (β-BaB2O4, BBO) nonlinear crystal. The focus is on determining the relevant χ(3) cubic tensor components that affect interaction of type I cascaded second-harmonic generation. Various experiments in the literat...

  15. Yielding and deformation behavior of the single crystal superalloy PWA 1480

    Science.gov (United States)

    Milligan, Walter W.; Antolovich, Stephen D.

    1987-01-01

    Interrupted tensile tests were conducted to fixed plastic strain levels in 100 ordered single crystals of the nickel based superalloy PWA 1480. Testing was done in the range of 20 to 1093 C, at strain rate of 0.5 and 50 percent/min. The yield strength was constant from 20 to 760 C, above which the strength dropped rapidly and became a strong function of strain rate. The high temperature data were represented very well by an Arrhenius type equation, which resulted in three distinct temperature regimes. The deformation substructures were grouped in the same three regimes, indicating that there was a fundamental relationship between the deformation mechanisms and activation energies. Models of the yielding process were considered, and it was found that no currently available model was fully applicable to this alloy. It was also demonstrated that the initial deformation mechanism (during yielding) was frequently different from that which would be inferred by examining specimens which were tested to failure.

  16. Nonlinear enhancement in photonic crystal slow light waveguides fabricated using CMOS-compatible process.

    Science.gov (United States)

    Shinkawa, Mizuki; Ishikura, Norihiro; Hama, Yosuke; Suzuki, Keijiro; Baba, Toshihiko

    2011-10-24

    We have studied low-dispersion slow light and its nonlinear enhancement in photonic crystal waveguides. In this work, we fabricated the waveguides using Si CMOS-compatible process. It enables us to integrate spotsize converters, which greatly simplifies the optical coupling from fibers as well as demonstration of the nonlinear enhancement. Two-photon absorption, self-phase modulation and four-wave mixing were observed clearly for picosecond pulses in a 200-μm-long device. In comparison with Si wire waveguides, a 60-120 fold higher nonlinearity was evaluated for a group index of 51. Unique intensity response also occurred due to the specific transmission spectrum and enhanced nonlinearities. Such slow light may add various functionalities in Si photonics, while loss reduction is desired for ensuring the advantage of slow light.

  17. Highly non-linear solid core photonic crystal fiber with one nano hole

    Science.gov (United States)

    Gangwar, Rahul Kumar; Bhardwaj, Vanita; Singh, Vinod Kumar

    2015-08-01

    The numerical study of newly designed solid core photonic crystal fiber (SCPCF) having three hexagonal air hole rings in cladding region and one small nano hole at the center are presented. By using full vectorial finite element method (FV-FEM), we analyses the optical properties like effective area, nonlinearity and confinement loss of the proposed PCF. Results show that the change in core diameter controls the effective area, nonlinearity and confinement loss. A low effective area (3.34 µm2), high nonlinearity (36.34 W-1km-1) and low confinement loss (0.00106 dB/km) are achieved at the communication wavelength 1.55 µm for the SCPCF having core air hole diameter 0.10 µm, cladding air holes diameter 1.00 µm and pitch 2.50 µm. This type of PCF is very useful in non-linear applications such as supercontinuum generation, four wave mixing, second harmonic generation etc.

  18. Directional dependence of nonlinear surface acoustic waves in the (001) plane of cubic crystals.

    Science.gov (United States)

    Kumon, R E; Hamilton, M F

    2002-05-01

    Spectral evolution equations are used to perform analytical and numerical studies of nonlinear surface acoustic waves in the (001) plane of a variety of nonpiezoelectric cubic crystals. The basic theory underlying the model equations is outlined, and quasilinear solutions of the equations are presented. Expressions are also developed for a characteristic length scale for nonlinear distortion and a nonlinearity coefficient. A time-domain equation corresponding to the spectral equations is derived. Numerical calculations based on measured second- and third-order elastic constants taken from the literature are performed to predict the evolution of initially monofrequency surface waves. Nonlinearity matrix elements that indicate the coupling strength of harmonic interactions are shown to provide a useful tool for characterizing waveform distortion. The formation of compression or rarefaction shocks can be strongly dependent on the direction of propagation, and harmonic generation is suppressed or increased in certain directions.

  19. Review of a New IR Nonlinear Optical BaGa4Se7 Crystal

    Institute of Scientific and Technical Information of China (English)

    Wen-Tao Xu; De-Gang Xu; Yu-Ye Wang; Peng-Xiang Liu; Wei Shi; Jian-Quan Yao

    2016-01-01

    A newly grown BaGa4Se7 crystal has been synthesized via the Bridgman-Stockbarger technique. This new crystal has advantages of high nonlinear optics (NLO) coefficients, high laser damage thresholds, and wide transparent regions. The BaGa4Se7 crystal has bright application prospects as a nonlinear gain medium in mid-infrared and terahertz regions. In this paper, the crystalline structure and synthetic method of the BaGa4Se7 crystal are introduced. The refractive indices and absorption coefficients along three dielectric axes between 0.1THz and 1.0THz are also obtained. The terahertz difference frequency generation (THz-DFG) characteristics based on the BaGa4Se7 crystal in the frequency range of 0.1THz to 1.0THz are analyzed theoretically and the phase-matching conditions are calculated. The application of BaGa4Se7 crystals in terahertz wave generation is also discussed.

  20. Quadratic nonlinear optical parameters of 7% MgO-doped LiNbO3 crystal

    Science.gov (United States)

    Kulyk, B.; Kapustianyk, V.; Figà, V.; Sahraoui, B.

    2016-06-01

    Pure and 7% MgO-doped lithium niobate (LiNbO3) single crystals were grown by the Czochralski technique. The shift of optical absorption edge in 7% MgO-doped crystal in direction of shorter wavelength compared to undoped crystal was observed. The second harmonic generation measurements of 7% MgO-doped LiNbO3 crystal were performed at room temperature by means of the rotational Maker fringe technique using Nd:YAG laser generating at 1064 nm in picoseconds regime. Experimentally obtained value of nonlinear optical coefficient d33 for 7% MgO-doped LiNbO3 was found to be less than for undoped crystal but higher than for 5% MgO-doped. I-type phase-matched second harmonic generation was achieved and the value of phase-matched angle was calculated. High quadratic nonlinearity together with tolerance to intensive laser irradiation makes 7% MgO-doped LiNbO3 crystal interesting for application in optoelectronics.

  1. Experimental study of strong nonlinear-optics effects in liquid crystals

    Science.gov (United States)

    Darbin, S. D.; Arakelyan, S. M.; Cheung, M. M.; Shen, Y. R.

    1984-07-01

    Nonlinear optical effects that arise in nematic liquid crystals as a result of a change in the index of refraction induced by a laser field are considered. Since the resultant nonlinearity is extremely high, the approximation of perturbation theory cannot be used in calculations. However, the change in refractive index results mainly in phase advance as waves propagate through a thin film of liquid crystal, while the change of intensity is significant. Moreover, if there is no change in polarization of the pumping field, calculations are relatively simple. An investigation is made of the propagation of a cross sectionally bounded laser beam through a homeotropically oriented liquid crystal, giving rise to spatial phase modulation of emission. When the intensity of the laser beam exceeds a certain value, a system of aberation rings is observed in the output radiation. Effects of dynamic self-diffraction accompanying degenerate four-wave mixing when a change in refractive index is induced in a homeotropic liquid crystal film, and optical bistability in a nonlinear Fabry-Perot optical cavity, as well as generation of a self-oscillatory state in such a resonator are discussed.

  2. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    Science.gov (United States)

    Vela, T.; Selvarajan, P.; Freeda, T. H.; Balasubramanian, K.

    2013-04-01

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV-visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated.

  3. Evaluation of suitability of AMT single crystal for optical limiting applications by performing structural, dielectric, mechanical, optical and third order nonlinearity characterization studies

    Science.gov (United States)

    Elavarasu, N.; Sathya, P.; Pugazhendhi, S.; Vijayan, N.; Maurya, K. K.; Gopalakrishnan, R.

    2016-10-01

    Ammonium D,L-Tartrate (AMT) single crystal for optical and photonic device application was analyzed with different characterization studies. The AMT crystal was grown by low cost conventional solution growth technique. The unit cell parameters were obtained from single crystal XRD analysis and the crystal system is confirmed to be orthorhombic with noncentrosymmetric space group P212121. The crystalline perfection evaluated by high resolution X-ray diffractometry (HRXRD) enumerates the quality of the crystal is good. The optical transparency window of AMT crystal has 78% transmittance from 234 nm to 1100 nm region and has lower cut-off wavelength of 234 nm was analyzed by UV-visible spectral studies. The hardness number (Hv), yield strength (σy) and elastic stiffness constant (C11) were evaluated from the hardness data using Vickers hardness tester. Dielectric study indicates the moderate dielectric constant and low dielectric loss of AMT crystal which are required properties to develop optoelectronic devices. The laser damage threshold value of AMT is 0.238 GW/cm2 and photoconductivity study reveals the positive photoconductivity nature of the AMT crystal. The particle size dependent SHG studies were performed using Nd:YAG laser. The SHG efficiency of AMT is found to be 1.3 times greater than the standard KDP crystal. Third order nonlinear susceptibility χ(3) of AMT was assessed using an open aperture and closed aperture Z-scan technique and the value is 6.71×10-6 esu. AMT crystal is found to exhibit good optical power limiting. The present work indicates that AMT is a potential material for optoelectronic and nonlinear optical devices.

  4. Growth and characterization of semiorganic nonlinear optical rubidium bis-DL-malato borate single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanian, D. [Post Graduate and Research Department of Physics, Pachaiyappa' s College, Chennai 600030 (India); Sankar, R. [Crystal Growth Centre, Anna University, Chennai 600025 (India); Shankar, V. Siva [Post Graduate and Research Department of Physics, Pachaiyappa' s College, Chennai 600030 (India); Murugakoothan, P. [Post Graduate and Research Department of Physics, Pachaiyappa' s College, Chennai 600030 (India)], E-mail: pmurugakoothan@yahoo.com; Arulmozhichelvan, P. [Post Graduate and Research Department of Physics, Pachaiyappa' s College, Chennai 600030 (India); Jayavel, R. [Crystal Growth Centre, Anna University, Chennai 600025 (India)

    2008-01-15

    A new semiorganic nonlinear optical rubidium bis-DL-malato borate (RBMB) has been synthesized and single crystals were grown by slow cooling technique from aqueous solution. The grown crystals have been characterized by X-ray diffraction (single crystal XRD) to confirm the formation of the crystalline phases. FT-IR and FT-Raman spectroscopic analyses confirm the presence of all the functional groups in the grown crystals. TG-DTA studies reveal that the material is stable up to 230 deg. C. The UV-vis transmission spectrum shows a lower cutoff wavelength of 230 nm. The emission of SHG using Nd:YAG laser is confirmed by a modified Kurtz and Perry powder setup.

  5. Synthesis, crystal growth and studies on non-linear optical property of new chalcones

    Science.gov (United States)

    Sarojini, B. K.; Narayana, B.; Ashalatha, B. V.; Indira, J.; Lobo, K. G.

    2006-09-01

    The synthesis, crystal growth and non-linear optical (NLO) property of new chalcone derivatives are reported. 4-Propyloxy and 4-butoxy benzaldehydes were made to under go Claisen-Schmidt condensation with 4-methoxy, 4-nitro and 4-phenoxy acetophenones to form corresponding chalcones. The newly synthesized compounds were characterized by analytical and spectral data. The Second harmonic generation (SHG) efficiency of these compounds was measured by powder technique using Nd:YAG laser. Among tested compounds three chalcones showed NLO property. The chalcone 1-(4-methoxyphenyl)-3-(4-propyloxy phenyl)-2-propen-1-one exhibited SHG conversion efficiency 2.7 times that of urea. The bulk crystal of 1-(4-methoxyphenyl)-3-(4-butoxyphenyl)-2-propen-1-one (crystal size 65×28×15 mm 3) was grown by slow-evaporation technique from acetone. Microhardness of the crystal was tested by Vicker's microhardness method.

  6. Nonlinear response studies and corrections for a liquid crystal spatial light modulator

    Indian Academy of Sciences (India)

    Ravinder Kumar Banyal; B Raghavendra Prasad

    2010-06-01

    The nonlinear response of light transmission characteristics of a liquid crystal (LC) spatial light modulator (SLM) is studied. The results show that the device exhibits a wide range of variations with different control parameters and input settings. Experiments were performed to obtain intensity modulation that is best described by either power-law or sigmoidal functions. Based on the inverse transformation, an appropriate pre-processing scheme for electrically addressed input gray-scale images, particularly important in several optical processing and imaging applications, is suggested. Further, the necessity to compensate the SLM image nonlinearities in a volume holographic data storage and retrieval system is demonstrated.

  7. Second-harmonic generation with zero group-velocity mismatch in nonlinear photonic crystal fibers

    DEFF Research Database (Denmark)

    Bache, Morten; Lægsgaard, Jesper; Bang, Ole;

    2006-01-01

    We consider an index-guiding silica photonic crystal fiber with a triangular hole-pattern and a periodically poled quadratic nonlinearity. By tuning the pitch and the relative size of the holes, second-harmonic generation with zero group-velocity mismatch is found to be feasible for any fundamental...... wavelength above 780 nm. The phase-velocity mismatch has a lower limit with coherence lengths in the micron range. The nonlinear strength is optimized when the fundamental has maximum confinement in the core. The conversion bandwidth allows for fs-pulse conversion and 4-180%/(Wmiddotcm2) relative...

  8. Anisotropy of Nonlinear-Optical Property of RCOB (R = Gd, Y) Crystal

    Institute of Scientific and Technical Information of China (English)

    WANG Zheng-Ping; WEI Jing-Qian; CHEN Huan-Chu; SHAO Zong-Shu; LIU Jun-Hai; SONG Ren-Bo; JIANG Huai-Dong; ZHANG Shu-Jun; FU Kun; WANG Chang-Qing; WANG Ji-Yang; LIU Yao-Gang

    2001-01-01

    The nonlinear-optical coefficients of RCOB (R = Gd, Y) crystals are measured. The spatial distribution of deff (effective nonlinear-optical coefficient) is subsequently determined. Our experiments show that the maximum deff occurs at the second quadrant. The second-harmonic generation efficiency reaches 48% for a 6 mm long, (113.2°,47.4°)-cut GdCOB, and 41.5% for a 5mm long, (113°, 36.5°)-cut YCOB, respectively. The intracavity frequency doubling of GdCOB is reported for the first time.

  9. On the theory of ternary melt crystallization with a non-linear phase diagram

    Science.gov (United States)

    Toropova, L. V.; Dubovoi, G. Yu; Alexandrov, D. V.

    2017-04-01

    The present study is concerned with a theoretical analysis of unidirectional solidification process of ternary melts in the presence of a phase transition (mushy) layer. A new analytical solution of heat and mass transfer equations describing the steady-state crystallization scenario is found with allowance for a non-linear liquidus equation. The model under consideration takes into account the presence of two phase transition layers, namely, the primary and cotectic mushy regions. We demonstrate that the phase diagram nonlinearity leads to substantial changes of analytical solutions.

  10. Synthesis, growth and optical properties of an efficient nonlinear optical single crystal: L-alanine DL-malic acid

    Science.gov (United States)

    Kirubagaran, R.; Madhavan, J.

    2015-02-01

    Single crystals of L-alanine DL-malic acid (LADLMA) have been grown from aqueous solution by slow-cooling technique. Powder X-ray diffraction studies reveal the structure of the crystal to be orthorhombic. The nonlinear optical conversion efficiency test was carried out for the grown crystals using the Kurtz powder technique. The third order nonlinear refractive index and the nonlinear absorption coefficient where evaluated by Z-scan measurements. As the material have a negative refractive index it could be used in the protection of optical sensors such as night vision devices.

  11. Third-order nonlinear and linear time-dependent dynamical diffraction of X-rays in crystals.

    Science.gov (United States)

    Balyan, Minas K

    2016-07-01

    For the first time the third-order nonlinear time-dependent Takagi's equations of X-rays in crystals are obtained and investigated. The third-order nonlinear and linear time-dependent dynamical diffraction of X-rays spatially restricted in the diffraction plane pulses in crystals is investigated theoretically. A method of solving the linear and the third-order nonlinear time-dependent Takagi's equations is proposed. Based on this method, results of analytical and numerical calculations for both linear and nonlinear diffraction cases are presented and compared.

  12. First principles crystal engineering of nonlinear optical materials. I. Prototypical case of urea

    Science.gov (United States)

    Masunov, Artëm E.; Tannu, Arman; Dyakov, Alexander A.; Matveeva, Anastasia D.; Freidzon, Alexandra Ya.; Odinokov, Alexey V.; Bagaturyants, Alexander A.

    2017-06-01

    The crystalline materials with nonlinear optical (NLO) properties are critically important for several technological applications, including nanophotonic and second harmonic generation devices. Urea is often considered to be a standard NLO material, due to the combination of non-centrosymmetric crystal packing and capacity for intramolecular charge transfer. Various approaches to crystal engineering of non-centrosymmetric molecular materials were reported in the literature. Here we propose using global lattice energy minimization to predict the crystal packing from the first principles. We developed a methodology that includes the following: (1) parameter derivation for polarizable force field AMOEBA; (2) local minimizations of crystal structures with these parameters, combined with the evolutionary algorithm for a global minimum search, implemented in program USPEX; (3) filtering out duplicate polymorphs produced; (4) reoptimization and final ranking based on density functional theory (DFT) with many-body dispersion (MBD) correction; and (5) prediction of the second-order susceptibility tensor by finite field approach. This methodology was applied to predict virtual urea polymorphs. After filtering based on packing similarity, only two distinct packing modes were predicted: one experimental and one hypothetical. DFT + MBD ranking established non-centrosymmetric crystal packing as the global minimum, in agreement with the experiment. Finite field approach was used to predict nonlinear susceptibility, and H-bonding was found to account for a 2.5-fold increase in molecular hyperpolarizability to the bulk value.

  13. Multiple-octave spanning mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    CERN Document Server

    Zhou, Binbin

    2016-01-01

    Bright and broadband coherent mid-IR radiation is important for exciting and probing molecular vibrations. Using cascaded nonlinearities in conventional quadratic nonlinear crystal like lithium niobate, self-defocusing near-IR solitons have been demonstrated that led to very broadband supercontinuum generation in the visible, near-IR and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal pumped in the mid-IR gives multiple-octave spanning supercontinua. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed (covering 1.6-$7.0~\\mu$m). The results were recorded in a commercially available crystal LiInS$_2$ pumped in the 3-$4~\\mu$m range, but other mid-IR crystals ...

  14. Enhanced optical nonlinearities in CMOS-compatible ultra-silicon-rich nitride photonic crystal waveguides

    Science.gov (United States)

    Sahin, E.; Ooi, K. J. A.; Chen, G. F. R.; Ng, D. K. T.; Png, C. E.; Tan, D. T. H.

    2017-09-01

    We present the design, fabrication, and characterization of photonic crystal waveguides (PhCWs) on an ultra-silicon-rich nitride (USRN) platform, with the goal of augmenting the optical nonlinearities. The design goals are to achieve an optimized group index curve on the PhCW band edge with a non-membrane PhCW with symmetric SiO2 undercladding and overcladding, so as to maintain back-end CMOS compatibility and better structural robustness. Linear optical characterization, as well as nonlinear optical characterization of PhCWs on ultra-silicon-rich nitride is performed at the telecommunication wavelengths. USRN's negligible two-photon absorption and free carrier losses at the telecommunication wavelengths ensure that there is no scaling of two-photon related losses with the group index, thus maintaining a high nonlinear efficiency. Self-phase modulation experiments are performed using a 96.6 μm PhCW. A 1.5π phase shift is achieved with an input peak power of 2.5 W implying an effective nonlinear parameter of 1.97 × 104 (W m)-1. This nonlinear parameter represents a 49× enhancement in the nonlinear parameter from the slow light effect, in good agreement with expected scaling from the measured group index.

  15. Microwave emission by nonlinear crystals irradiated with a high-intensity, mode-locked laser

    CERN Document Server

    Borghesani, A F; Guarise, M

    2016-01-01

    We report on the experimental investigation of the efficiency of some nonlinear crystals to generate microwave (RF) radiation as a result of optical rectification (OR) when irradiated with intense pulse trains delivered by a mode-locked laser at $1064\\,$nm. We have investigated lithium triborate (LBO), lithium niobate (LiNbO$_3$), zinc selenide (ZnSe), and also potassium titanyl orthophosphate (KTP) for comparison with previous measurements. The results are in good agreement with the theoretical predictions based on the form of the second-order nonlinear susceptibility tensor. For some crystals we investigated also the second harmonic generation (SHG) to cross check the theoretical model. We confirm the theoretical prediction that OR leads to the production of higher order RF harmonics that are overtones of the laser repetition rate.

  16. Growth and characterization of organic nonlinear optical single crystal 2,7-dihydroxy naphthalene

    Science.gov (United States)

    Sadhasivam, S.; Rajesh, N. P.

    2017-08-01

    The organic nonlinear optical crystals of 2,7-dihydroxy naphthalene (2,7-DN) were grown by slow evaporation method using acetone as a solvent. Optically transparent single crystal with sizes up to 15 × 7 × 4 mm3 were grown. Non-centrosymmetry has been studied using X-ray diffraction (XRD) and functional group of 2,7-DN were studied by Raman scattering and FTIR spectral analysis. The optical transmittance was characterized and to be 28%. The melting point of 2,7-DN is 465 K. 2,7-DN found exhibit low dielectric constant of 20-22 in the frequency range of 10 Hz-10 MHz at room temperature. The nonlinear optical and phase matching properties were characterized by Kurtz powder second harmonic generation (SHG) efficiency test.

  17. Saturable Nonlinearity in Photovoltaic-Photorefractive Crystals Under Open-circuit Condition

    Institute of Scientific and Technical Information of China (English)

    GUO Ru; LING Zhen-Fang; CHEN Xiao-Hu; ZHANG Guo-Quan; ZHANG Xin-Zheng; WEN Hai-Dong; JIANG Ying; LIU Si-Min

    2000-01-01

    We show that the refractive index change induced by a focused incident beam with an additional incoherent uniform illumination in photovoltaic-photorefractive crystals under open-circuit condition has a saturable nonlinearity form. The incoherent uniform background illumination can be used to increase the effective dark irradiance. The formation time of the photovoltaic soliton can be decreased by keeping the intensity of the soliton at a higher value without over-saturation by use of the background illumination.

  18. Measuring nonlinear stresses generated by defects in 3D colloidal crystals

    CERN Document Server

    Lin, Neil Y C; Schall, Peter; Sethna, James P; Cohen, Itai

    2016-01-01

    The mechanical, structural and functional properties of crystals are determined by their defects and the distribution of stresses surrounding these defects has broad implications for the understanding of transport phenomena. When the defect density rises to levels routinely found in real-world materials, transport is governed by local stresses that are predominantly nonlinear. Such stress fields however, cannot be measured using conventional bulk and local measurement techniques. Here, we report direct and spatially resolved experimental measurements of the nonlinear stresses surrounding colloidal crystalline defect cores, and show that the stresses at vacancy cores generate attractive interactions between them. We also directly visualize the softening of crystalline regions surrounding dislocation cores, and find that stress fluctuations in quiescent polycrystals are uniformly distributed rather than localized at grain boundaries, as is the case in strained atomic polycrystals. Nonlinear stress measurements ...

  19. Nonlinear frequency conversion effect in a one-dimensional graphene-based photonic crystal

    Science.gov (United States)

    Wicharn, S.; Buranasiri, P.

    2015-07-01

    In this research, the nonlinear frequency conversion effect based on four-wave mixing (FWM) principle in a onedimensional graphene-based photonics crystal (1D-GPC) has been investigated numerically. The 1D-GPC structure is composed of two periodically alternating material layers, which are graphene-silicon dioxide bilayer system and silicon membrane. Since, the third-order nonlinear susceptibility χ(3) of bilayer system is hundred time higher than pure silicon dioxide layer, so the enhancement of FWM response can be achieved inside the structure with optimizing photon energy being much higher than a chemical potential level (μ) of graphene sheet. In addition, the conversion efficiencies of 1DGPC structure are compared with chalcogenide based photonic structure for showing that 1D-GPC structure can enhance nonlinear effect by a factor of 100 above the chalcogenide based structure with the same structure length.

  20. Extreme events induced by self-action of laser beams in dynamic nonlinear liquid crystal cells

    Science.gov (United States)

    Bugaychuk, S.; Iljin, A.; Chunikhina, K.

    2017-06-01

    Optical extreme events represent a feature of nonlinear systems where there may emerge individual pulses possessing very high (or very low) intensity hardly probable statistically. Such property is being connected with the generation of solitons in the nonlinear systems. We carry out the first experiments for detection of extreme events during two-wave mixing with nonlinear dynamical liquid crystal (LC) cells. We investigate the statistics of the extreme events in dependence on relation between the duration of a laser pulse and the time characteristic of dynamic grating relaxation in LC cell. Our research shows that the self-diffraction of laser beams with a dynamical grating support the generation of envelope solitons in this system.

  1. Design of broadband nearly-zero flattened dispersion highly nonlinear photonic crystal fiber

    Institute of Scientific and Technical Information of China (English)

    Shuqin Lou; Hong Fang; Honglei Li; Tieying Guo; Lei Yao; Liwen Wang; Weiguo Chen; Shuisheng Jian

    2008-01-01

    We propose a new structure of broadband nearly-zero flattened dispersion highly nonlinear photonic crystal fiber (PCF). Through optimizing the diameters of the first two inner rings of air-holes and the GeO2 doping concentration of the core, the nonlinear coefficient is up to 47 W-1.km-1 at the wavelength of 1.55 μm and nearly-zero flattened dispersion of±0.5 ps/(nm.km) is achieved in the telecommunication window (1460 - 1625 nm). Due to the use of GeO2-doped core, this innovative structure can offer not only a large nonlinear coefficient and broadband nearly-zero flattened dispersion but also low leakage losses.

  2. Modelling a nonlinear optical switching in a standard photonic crystal fiber infiltrated with carbon disulfide

    Science.gov (United States)

    Munera, Natalia; Acuna Herrera, Rodrigo

    2016-06-01

    In this letter, a numerical analysis is developed for the propagation of ultrafast optical pulses through a standard photonic crystal fiber (PCF) consisting of two infiltrated holes using carbon disulfide (CS2). This material is a good choice since it has highly nonlinear properties, what makes it a good candidate for optical switching and broadband source at low power compared to traditional nonlinear fiber coupler. Based on supermodes theory, a set of generalized nonlinear equations is presented in order to study the propagation characteristics. It is shown in this letter that it is possible to get optical switching behavior at low power and how the dispersion, as well as, the two infiltrated holes separation influence this effect. Finally, we see that supercontinuum generation can be induced equally in both infiltrated holes despite no initial excitation at one hole.

  3. Investigation on the growth, spectral, lifetime, mechanical analysis and third-order nonlinear optical studies of L-methionine admixtured D-mandelic acid single crystal: A promising material for nonlinear optical applications

    Science.gov (United States)

    Jayaprakash, P.; Sangeetha, P.; Kumari, C. Rathika Thaya; Caroline, M. Lydia

    2017-08-01

    A nonlinear optical bulk single crystal of L-methionine admixtured D-mandelic acid (LMDMA) has been grown by slow solvent evaporation technique using water as solvent at ambient temperature. The crystallized LMDMA single crystal subjected to single crystal X-ray diffraction study confirmed monoclinic system with the acentric space group P21. The FTIR analysis gives information about the modes of vibration in the various functional groups present in LMDMA. The UV-visible spectral analysis assessed the optical quality and linear optical properties such as extinction coefficient, reflectance, refractive index and from which optical conductivity and electric susceptibility were also evaluated. The frequency doubling efficiency was observed using Kurtz Perry powder technique. A multiple shot laser was utilized to evaluate the laser damage threshold energy of the crystal. Discrete thermodynamic properties were carried out by TG-DTA studies. The hardness, Meyer's index, yield strength, elastic stiffness constant, Knoop hardness, fracture toughness and brittleness index were analyzed using Vickers microhardness tester. Layer growth pattern and the surface defect were examined by chemical etching studies using optical microscope. Fluorescence emission spectrum was recorded and lifetime was also studied. The electric field response of crystal was investigated from the dielectric studies at various temperatures at different frequencies. The third-order nonlinear optical response in LMDMA has been investigated using Z-scan technique with He-Ne laser at 632.8 nm and nonlinear parameters such as refractive index (n2), absorption coefficient (β) and susceptibility (χ3) investigated extensively for they are in optical phase conjucation, high-speed optical switches and optical dielectric devices.

  4. Bulk crystal growth and nonlinear optical characterization of semiorganic single crystal: Cadmium (II) dibromide L - Proline monohydrate

    Energy Technology Data Exchange (ETDEWEB)

    Balakrishnan, T., E-mail: balacrystalgrowth@gmail.com [Crystal Growth Laboratory, PG & Research Department of Physics, Periyar EVR College (Autonomous), Tiruchirappalli, 620 023, Tamil Nadu (India); Sathiskumar, S. [Crystal Growth Laboratory, PG & Research Department of Physics, Periyar EVR College (Autonomous), Tiruchirappalli, 620 023, Tamil Nadu (India); Ramamurthi, K. [Crystal Growth and Thin Film Laboratory, Department of Physics and Nanotechnology, SRM University, Kattankulathur, 603 203, Kancheepuram, Tamil Nadu (India); Thamotharan, S. [Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA University, Thanjavur, 613 401 (India)

    2017-01-15

    Single crystal of a novel metal organic nonlinear optical (NLO) cadmium (II) dibromide L - proline monohydrate (CBLPM) of size 7 × 7 × 5 mm{sup 3} was grown from slow evaporation technique. Single crystal X – ray diffraction analysis reveals that the crystal belongs to orthorhombic system with lattice parameters a = 10.1891 (8) Å, b = 13.4961 (11) Å, c = 7.4491 (5) Å and space group P2{sub 1}2{sub 1}2{sub 1}. The powder X – ray diffraction pattern of CBLPM was recorded and the X – ray diffraction peaks were indexed. The various functional groups of CBLPM were identified by the FT – IR and FT – Raman spectral analyses. The optical transmittance window and lower cut off wavelength of CBLPM were identified from UV – Vis – NIR studies. The mechanical strength of the grown crystal was estimated using Vickers microhardness test. Dielectric constant and dielectric loss measurements were carried out at different temperatures in the frequency range of 50 Hz - 2 MHz. The photoluminescence spectrum was recorded in the wavelength range 200–400 nm and the estimated optical band gap was ∼4.1 eV. Etching studies were carried out for different etching time. Thermal stability of CBLPM was determined using thermogravimetric analysis. Laser induced damage threshold study was carried out for the grown crystal using Nd:YAG laser. Size dependent second harmonic generation efficiency of the grown crystal was determined by Kurtz and Perry powder technique with different particle size using Nd:YAG laser with wavelength 1064 nm. Second harmonic generation efficiency of the powdered CBLPM crystal was ∼2.3 times that of potassium dihydrogen orthophosphate. - Highlights: • CBLPM crystal belongs to orthorhombic crystal system with space group P2{sub 1}2{sub 1}2{sub 1.} • Transmittance of CBLPM is ∼80% in the 650–1100 nm range. • Powder SHG efficiency of CBLPM increases with increase in particle size. • SHG efficiency of 0.57 μm size powdered CBLPM is ∼2

  5. On-chip steering of entangled photons in nonlinear photonic crystals.

    Science.gov (United States)

    Leng, H Y; Yu, X Q; Gong, Y X; Xu, P; Xie, Z D; Jin, H; Zhang, C; Zhu, S N

    2011-08-16

    One promising technique for working toward practical photonic quantum technologies is to implement multiple operations on a monolithic chip, thereby improving stability, scalability and miniaturization. The on-chip spatial control of entangled photons will certainly benefit numerous applications, including quantum imaging, quantum lithography, quantum metrology and quantum computation. However, external optical elements are usually required to spatially control the entangled photons. Here we present the first experimental demonstration of on-chip spatial control of entangled photons, based on a domain-engineered nonlinear photonic crystal. We manipulate the entangled photons using the inherent properties of the crystal during the parametric downconversion, demonstrating two-photon focusing and beam-splitting from a periodically poled lithium tantalate crystal with a parabolic phase profile. These experimental results indicate that versatile and precise spatial control of entangled photons is achievable. Because they may be operated independent of any bulk optical elements, domain-engineered nonlinear photonic crystals may prove to be a valuable ingredient in on-chip integrated quantum optics.

  6. Comment on the paper: "Crystal growth and spectroscopic characterization of Aloevera amino acid added lithium sulfate monohydrate: a non-linear optical crystal".

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R

    2015-01-05

    The title paper (Manimekalai et al., 2014) reports a slow evaporation solution growth of a so called 'Aloevera amino acid added lithium sulfate monohydrate' (AALSMH) crystal. In this communication, many points of criticism, concerning the crystal growth, NMR spectrum and X-ray powder pattern of this so called AALSMH nonlinear optical crystal are highlighted. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Growth and characterization of glycinium 3-nitrophthalate nonlinear optical single crystal

    Science.gov (United States)

    Bhuvaneswari, R.; Bharathi, M. Divya; Hemanathan, K.; Murugesan, K. Sakthi

    2017-05-01

    The potential organic nonlinear optical single crystal of glycinium 3-nitrophthalate has been grown by slow evaporation solution growth technique (SEST) using water solution at room temperature. The single crystal x-ray diffraction confirms the monoclinic structure with the centro symmetric space group P21/c. The crystal shows good transparency about (80%) in the entire visible region with a lower cut off wavelength of 377nm. The physico-chemical changes, stability and decomposition stages of the Glycinium 3-Nitrophthalate compound were established by TG-DSC studies. The laser induced surface damage threshold value 6.2 GW/cm2 indicates that this material can be used for high power laser applications.

  8. Absolute measurement of the effective nonlinearities of KTP and BBO crystals by optical parametric amplification.

    Science.gov (United States)

    Armstrong, D J; Alford, W J; Raymond, T D; Smith, A V

    1996-04-20

    Absolute magnitudes of the effective nonlinearity, deff, were measured for seven KTP and six BBO crystals. The d(eff), were derived from the parametric gain of an 800-nm signal wave in the sample crystals when they were pumped by the frequency-doubled, spatially filtered light from an injectionseeded, Q-switched Nd:YAG laser. The KTP crystals, all type II phase matched with propagation in the X-Z plane, had d(eff) values ranging from 1.97 to 3.50 pm/V. Measurements of gain as a function of phase velocity mismatch indicate that two of the KTP crystals clearly contain multiple ferroelectric domains. For five type I phase-matched BBO crystals, d(eff) ranged from 1.76 to 1.83 pm/V, and a single type II phase-matched BBO crystal had a d(eff) of 1.56 pm/V. The uncertainty in our measurements of d(eff) values is ±5% for KTP and ±10% for BBO.

  9. Wave propagation in photonic crystals and metamaterials: Surface waves, nonlinearity and chirality

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bingnan [Iowa State Univ., Ames, IA (United States)

    2009-01-01

    Photonic crystals and metamaterials, both composed of artificial structures, are two interesting areas in electromagnetism and optics. New phenomena in photonic crystals and metamaterials are being discovered, including some not found in natural materials. This thesis presents my research work in the two areas. Photonic crystals are periodically arranged artificial structures, mostly made from dielectric materials, with period on the same order of the wavelength of the working electromagnetic wave. The wave propagation in photonic crystals is determined by the Bragg scattering of the periodic structure. Photonic band-gaps can be present for a properly designed photonic crystal. Electromagnetic waves with frequency within the range of the band-gap are suppressed from propagating in the photonic crystal. With surface defects, a photonic crystal could support surface modes that are localized on the surface of the crystal, with mode frequencies within the band-gap. With line defects, a photonic crystal could allow the propagation of electromagnetic waves along the channels. The study of surface modes and waveguiding properties of a 2D photonic crystal will be presented in Chapter 1. Metamaterials are generally composed of artificial structures with sizes one order smaller than the wavelength and can be approximated as effective media. Effective macroscopic parameters such as electric permittivity ϵ, magnetic permeability μ are used to characterize the wave propagation in metamaterials. The fundamental structures of the metamaterials affect strongly their macroscopic properties. By designing the fundamental structures of the metamaterials, the effective parameters can be tuned and different electromagnetic properties can be achieved. One important aspect of metamaterial research is to get artificial magnetism. Metallic split-ring resonators (SRRs) and variants are widely used to build magnetic metamaterials with effective μ < 1 or even μ < 0. Varactor based

  10. A high-speed demultiplexer based on a nonlinear optical loop mirror with a photonic crystal fiber

    DEFF Research Database (Denmark)

    Siahlo, Andrei; Oxenløwe, Leif Katsuo; Berg, Kim Skaalum

    2003-01-01

    A 50-m-long photonic crystal fiber with zero-dispersion wavelength at 1552 nm is used as the nonlinear medium in a nonlinear optical loop-mirror-based demultiplexer. The successful demultiplexing of an 80-Gb/s optical time-division multiplexing signal transmitted through an 80-km span of standard...

  11. Nonlinear ultrafast switching based on soliton self-trapping in dual-core photonic crystal fibre

    Science.gov (United States)

    Stajanca, P.; Bugar, I.

    2016-11-01

    In this paper, we present a systematic numerical study of a novel ultrafast nonlinear switching concept based on soliton self-trapping in dual-core (DC) photonic crystal fibre (PCF). The geometrical parameters of highly-nonlinear (HN) DC microstructure are optimized with regard to desired linear and nonlinear propagation characteristics. The comparable magnitude of fibre coupling length and soliton period is identified as a key condition for presented switching concept. The optimized DC PCF design is subjected to detailed nonlinear numerical study. Complex temporal-spectral-spatial transformations of 100 fs hyperbolic secant pulse at 1550 nm in the DC PCF are studied numerically employing a model based on coupled generalized nonlinear Schrödinger equations solved by a split-step Fourier method. For the optimized DC structure, mutual interplay of solitonic and coupling processes gives rise to nonlinear switching of self-trapped soliton. The output channel (fibre core) for the generated soliton can be controlled via the input pulse energy. For vertical polarization, the optimal soliton switching with extinction ratio contrast of 32.4 dB at 10.75 mm propagation distance is achieved. Even better switching contrast of 34.8 dB can be achieved for horizontal polarization at optimal propagation distance of 10.25 mm. Besides energy-controlled soliton self-trapping switching, the fibre supports also nonlinear polarization switching with soliton switching contrast as high as 37.4 dB. The proposed fibre holds a high application potential allowing efficient ultrafast switching of sub-nanojoule pulses at over-Tb/s data rates requiring only about 1 cm fibre length.

  12. Light yield of an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin

    CERN Document Server

    Liu, Jing; Soma, Arun Kumar

    2016-01-01

    A light yield of 20.4 $\\pm$ 0.8 photoelectrons/keV was achieved with an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin. This is by far the largest yield in the world achieved with CsI crystals. An energy threshold that is several times lower than the current dark matter experiments utilizing CsI(Tl) crystals may be achievable using this technique. Together with novel CsI crystal purification methods, the technique may be used to improve the sensitivities of dark matter and coherent elastic neutrino-nucleus scattering experiments. Also measured were the scintillation light decay constants of the undoped CsI crystal at both room temperature and 77 Kelvin. The results are consistent with those in the literature.

  13. Controlling light with high-Q silicon photonic crystal nanocavities: Photon confinement, nonlinearity and coherence

    Science.gov (United States)

    Yang, Xiaodong

    The strong light localization and long photon lifetimes in two-dimensional silicon photonic crystal nanocavities with high quality factor (Q ) and subwavelength modal volume (V) significantly enhance the light-matter interactions, presenting many opportunities to explore new functionalities in silicon nanophotonic integrated circuits for on-chip all-optical information processing, optical computation and optical communications. This thesis will focus on the design, nanofabrication, and experimental characterization of both passive and active silicon nanophotonic devices based on two-dimensional high-Q silicon photonic crystal nanocavities. Three topics of controlling light with these high-Q nanocavities will be presented, including (1) photon confinement mechanism and cavity resonance tuning, (2) enhancement of optical nonlinearities, and (3) all-optical analogue to coherent interferences. The first topic is photon confinement in two-dimensional high- Q silicon photonic crystal nanocavities. In Chapter 2, the role of Q/V as the figure of merit for the enhanced light-matter interaction in optical microcavities and nanocavities is explained and different types of high-Q optical microcavities and nanocavities are reviewed with an emphasis on two-dimensional photonic crystal nanocavities. Then the nanofabrication process and the Q characterization are illustrated for the two-dimensional silicon photonic crystal nanocavities. In Chapter 3, the post-fabrication digital resonance tuning of high-Q silicon photonic crystal nanocavities using atomic layer deposition is proposed and demonstrated, with wide tuning range and precise control of cavity resonances while preserving high quality factors. The second topic is the enhancement of optical nonlinearities in two-dimensional high-Q silicon photonic crystal nanocavities, including stimulated Raman scattering and thermo-optical nonlinearities. In Chapter 4, the enhanced stimulated Raman scattering for low threshold Raman

  14. Studies on L-citrulline doped potassium dihydrogen phosphate- A non linear crystal with significant nonlinear properties

    Science.gov (United States)

    Sreevalsa, V. G.; Jayalekshmi, S.

    2014-01-01

    Potassium Dihydrogen Phosphate (KDP) single crystal is considered as one of the best representative of nonlinear optical crystals. Recently, amino acids having excellent nonlinear optical characteristics are being investigated as prospective dopants to improve the non linear optical characteristics of KDP. The present work is an attempt in this direction and L citrulline, one of the non essential amino acids showing good non linear optical characteristics is used as the dopant for KDP. Good quality crystals of L-citrulline doped KDP crystals were grown by slow evaporation technique. From the powder X-ray diffraction studies of doped KDP crystal, the structure of the doped crystals was determined by direct method and refined by Pawley method employing Topaz version program using the single crystal X-ray data for pure KDP. The lattice parameters for L citrulline doped KDP are a=7.467A0, b=7.467 A0, c=6.977 A0. The crystal falls into the tetragonal crystal system with space group I42 d. The presence of carbon and oxygen, which are primary components of amino acids, in the EDAX spectrum confirms the effectiveness of doping. The absorption spectra of the doped samples show that the crystals are transparent in the entire visible region. The second harmonic generation efficiency of the doped samples was determined by Kurtz powder technique using the Q-switched Nd:YAG laser beam and is found to be 2.2 times that of KDP. The nonlinear optical properties can be well studied by the open aperture Z scan technique. The open aperture curve exhibits a normalized transmittance valley. The nonlinear absorption coefficient β is obtained by theoretical fitting for two photon absorption. It is inferred that doping KDP with L citrulline has enhanced the nonlinearity considerably. This obviously suggests the potentiality of the crystal as an optical power limiter and also for various optical device applications.

  15. Comments on: “Crystal growth and comparison of vibrational and thermal properties of semi-organic nonlinear optical materials”

    Indian Academy of Sciences (India)

    Srinivasan Bikshandarkoil R; Fernandes Royle

    2016-03-01

    In {\\it Pramana – J. Phys. } 75, 683 (2010), Gunasekaran et al reported that they have grown the nonlinear optical crystals, urea thiourea mercuric chloride (UTHC) and urea thiourea mercuric sulphate (UTHS).We argue that UTHC and UTHS are dubious crystals and are not what the authors propose.

  16. Numerical analysis of nonlinear electromagnetic waves in nematic liquid crystal cells

    Science.gov (United States)

    Papanicolaou, N. C.; Christou, M. A.; Polycarpou, A. C.

    2012-10-01

    In the current work, the nonlinear problem of electromagnetic wave propagation in a Nematic Liquid Crystal (NLC) cell is solved numerically. The LC is sandwiched between two glass layers of finite thickness and a linearly polarized beam is obliquely incident to the cell. The dielectric properties of N-LCs depend on the tilt angle of the directors. When the excitation beam enters the cell, and providing the incident intensity is above the Fréedericksz threshold, the directors reorient themselves changing the LC's relative permittivity tensor. In turn, this affects beam propagation throughout the crystal. The electromagnetic field is modeled by the time-harmonic Maxwell equations whereas the director field is governed by a nonlinear ordinary differential equation (ODE). Our solution method is iterative, consistently taking into account this interaction between the excitation beam and the director field. The Maxwell equations are solved employing the Mode-Matching Technique (MMT). The solution of the nonlinear differential equation for the director field is obtained with the aid of a finite difference (FD) scheme.

  17. Multifunctional Bi2ZnOB2O6 single crystals for second and third order nonlinear optical applications

    Science.gov (United States)

    Iliopoulos, K.; Kasprowicz, D.; Majchrowski, A.; Michalski, E.; Gindre, D.; Sahraoui, B.

    2013-12-01

    Bi2ZnOB2O6 nonlinear optical single crystals were grown by means of the Kyropoulos method from stoichiometric melt. The second and third harmonic generation (SHG/THG) of Bi2ZnOB2O6 crystals were investigated by the SHG/THG Maker fringes technique. Moreover, SHG microscopy studies were carried out providing two-dimensional SHG images as a function of the incident laser polarization. The high nonlinear optical efficiency combined with the possibility to grow high quality crystals make Bi2ZnOB2O6 an excellent candidate for photonic applications.

  18. Highly non-linear solid core photonic crystal fiber with one nano hole

    Energy Technology Data Exchange (ETDEWEB)

    Gangwar, Rahul Kumar, E-mail: rahul0889@gmail.com; Bhardwaj, Vanita, E-mail: bhardwajphy12@gmail.com; Singh, Vinod Kumar, E-mail: singh.vk.ap@ismdhanbad.co.in [Department of Applied Physics, Indian School of Mines, Dhanbad, Jharkhand (India)

    2015-08-28

    The numerical study of newly designed solid core photonic crystal fiber (SCPCF) having three hexagonal air hole rings in cladding region and one small nano hole at the center are presented. By using full vectorial finite element method (FV-FEM), we analyses the optical properties like effective area, nonlinearity and confinement loss of the proposed PCF. Results show that the change in core diameter controls the effective area, nonlinearity and confinement loss. A low effective area (3.34 µm{sup 2}), high nonlinearity (36.34 W{sup −1}km{sup −1}) and low confinement loss (0.00106 dB/km) are achieved at the communication wavelength 1.55 µm for the SCPCF having core air hole diameter 0.10 µm, cladding air holes diameter 1.00 µm and pitch 2.50 µm. This type of PCF is very useful in non-linear applications such as supercontinuum generation, four wave mixing, second harmonic generation etc.

  19. Characterizations of nonlinear optical properties on GaN crystals in polar, nonpolar, and semipolar orientations

    Science.gov (United States)

    Chen, Hong; Huang, Xuanqi; Fu, Houqiang; Lu, Zhijian; Zhang, Xiaodong; Montes, Jossue A.; Zhao, Yuji

    2017-05-01

    We report the basic nonlinear optical properties, namely, two-photon absorption coefficient ( β ), three-photon absorption coefficient ( γ ), and Kerr nonlinear refractive index ( n kerr), of GaN crystals in polar c-plane, nonpolar m-plane, and semipolar ( 20 21 ¯ ) plane orientations. A typical Z-scan technique was used for the measurement with a femtosecond Ti:S laser from wavelengths of 724 nm to 840 nm. For the two-photon absorption coefficient ( β ), similar values were obtained for polar, nonpolar, and semipolar samples, which are characterized to be ˜0.90 cm/GW at 724 nm and ˜0.65 cm/GW at 730 nm for all the three samples. For the Kerr nonlinear refractive index ( n kerr), self-focusing features were observed in this work, which is different from previous reports where self-defocusing features were observed on GaN in the visible and near-UV spectral regions. At 724 nm, n kerr was measured to be ˜2.5 0 × 10 - 14 cm 2 / W for all three samples. Three-photon absorption coefficients ( γ ) were also determined, which were found to be consistent with previous reports. This study provides valuable information on the basic nonlinear optical properties of III-nitride semiconductors, which are vital for a wide range of applications such as integrated photonics and quantum photonics.

  20. Solitons and vortices in nonlinear two-dimensional photonic crystals of the Kronig-Penney type.

    Science.gov (United States)

    Mayteevarunyoo, Thawatchai; Malomed, Boris A; Roeksabutr, Athikom

    2011-08-29

    Solitons in the model of nonlinear photonic crystals with the transverse structure based on two-dimensional (2D) quadratic- or rhombic-shaped Kronig-Penney (KP) lattices are studied by means of numerical methods. The model can also applies to a Bose-Einstein condensate (BEC) trapped in a superposition of linear and nonlinear 2D periodic potentials. The analysis is chiefly presented for the self-repulsive nonlinearity, which gives rise to several species of stable fundamental gap solitons, dipoles, four-peak complexes, and vortices in two finite bandgaps of the underlying spectrum. Stable solitons with complex shapes are found, in particular, in the second bandgap of the KP lattice with the rhombic structure. The stability of the localized modes is analyzed in terms of eigenvalues of small perturbations, and tested in direct simulations. Depending on the value of the KP's duty cycle (DC, i.e., the ratio of the void's width to the lattice period), an internal stability boundary for the solitons and vortices may exist inside of the first bandgap. Otherwise, the families of the localized modes are entirely stable or unstable in the bandgaps. With the self-attractive nonlinearity, only unstable solitons and vortices are found in the semi-infinite gap.

  1. Tuning the dielectric properties of thiourea analog crystals for efficient nonlinear optical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sabari Girisun, T.C. [Department of Physics, Bishop Heber College, Tiruchirappalli 620 017, Tamil Nadu (India); School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu (India); Dhanuskodi, S., E-mail: dhanus2k3@yahoo.com [School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu (India)

    2010-01-15

    Materials with low dielectric constant have attracted a great deal of interest in the field of nonlinear applications and microelectronic industry. Metal complexes of thiourea with group II transition metals (Zn, Cd) as central atom and period III elements (S, Cl) were synthesized by chemical reaction method and single crystals were grown from aqueous solution by slow evaporation method. By parallel plate capacitor technique, the dielectric response, dissipation factor, ac conductivity and impedance of virgin and metal complexes have been studied in the frequency (100 Hz to 5 MHz) and temperature (303-423 K) ranges. Metal complexes of thiourea with cadmium substitute have a low dielectric constant less than 10. Also the presence of chlorine in the metal complex induces noncentro symmetric structure. Hence the role of group II transition metals and period III elements in tuning the dielectric properties for efficient nonlinear applications has been studied.

  2. Energy Squeeze of Ultrashort Light Pulse by Kerr Nonlinear Photonic Crystals

    Institute of Scientific and Technical Information of China (English)

    LIU Ye; ZHOU Fei; ZHANG Dao-Zhong; LI Zhi-Yuan

    2009-01-01

    Self-phase modulation can efficiently shape the spectrum of an optical pulse propagating along an optical material with Kerr nonlinearity. In this work we show that a one-dimensional Kerr nonlinear photonic crystal can impose anomalous spectrum modulation to a high-power ultrashort light pulse. The spectrum component at the photonic band gap edge can be one order of magnitude enhanced in addition to the ordinary spectrum broadening due to self-phase modulation. The enhancement is strictly pinned at the band gap edge by changing the sample length, the intensity or central wavelength of the incident pulse. The phenomenon is attributed to band gap induced enhancement of light-matter interaction.

  3. Polarization maintaining highly nonlinear photonic crystal fiber with closely lying two zero dispersion wavelengths

    Science.gov (United States)

    Hasan, Md. Rabiul; Anower, Md. Shamim; Hasan, Md. Imran

    2016-05-01

    A simple hexagonal photonic crystal fiber is proposed to simultaneously achieve ultrahigh birefringence, large nonlinear coefficient, and two zero dispersion wavelengths (ZDWs). The finite element method with circular perfectly matched layer boundary condition is used to simulate the designed structure. Simulation results show that it is possible to achieve two closely lying ZDWs of 1.08 and 1.29 μm for x-polarization with 0.88 and 1.20 μm for y-polarization modes, respectively. In addition, an ultrahigh birefringence of 3.15×10-2 and a high nonlinear coefficient of 58 W-1 km-1 are also obtained at the excitation wavelength of 1.55 μm. The proposed fiber can have important applications in supercontinuum generation, parametric amplification, four-wave mixing, and optical sensors design.

  4. Nonlinear chirped-pulse propagation and supercontinuum generation in photonic crystal fibers.

    Science.gov (United States)

    Hu, Xiaohong; Wang, Yishan; Zhao, Wei; Yang, Zhi; Zhang, Wei; Li, Cheng; Wang, Hushan

    2010-09-10

    Based on the generalized nonlinear Schrödinger equation and waveguiding properties typical of the photonic crystal fiber structure, nonlinear chirped-pulse propagation and supercontinua generation in the femtosecond and picosecond regimes are investigated numerically. The simulation results indicate that an input chirp parameter mainly affects the initial stage of spectral broadening caused by the self-phase modulation (SPM) effect. In the femtosecond regime where the SPM effect plays an important role in the process of spectral broadening, an input positive chirp can enhance the supercontinuum bandwidth through a modified pulse compression phase and a decreased propagation distance required by soliton fission. In the picosecond regime, where the SPM effect contributes less to the continuum bandwidth and four-wave mixing process or modulational instability dominates the initial stage of spectral and temporal evolution, the output spectral shape and bandwidths are less sensitive to the input chirp parameters.

  5. High Pressure Gases in Hollow Core Photonic Crystal Fiber:A New Nonlinear Medium

    CERN Document Server

    Azhar, Mohiudeen; Chang, Wonkeun; Joly, Nicolas; Russell, Philip

    2012-01-01

    The effective Kerr nonlinearity of hollow-core kagome-style photonic crystal fiber (PCF) filled with argon gas increases over 100 times when the pressure is increased from 1 to 150 bar, reaching 15 % of that of bulk silica glass, while the zero dispersion wavelength shifts from 300 to 900 nm. The group velocity dispersion of the system is uniquely pressure-tunable over a wide range while avoiding Raman scattering : absent in noble gases and having an extremely high optical damage threshold. As a result, detailed and well controlled studies of nonlinear effects can be performed, in both normal and anomalous dispersion regimes, using only a fixed-frequency pump laser. For example, the absence of Raman scattering permits clean observation, at high powers, of the interaction between a modulational instability side-band and a soliton created dispersive wave. Excellent agreement is obtained between numerical simulations and experimental results. The system has great potential for the realisation of reconfigurable s...

  6. All-optical diode effect of a nonlinear photonic crystal with a defect

    Institute of Scientific and Technical Information of China (English)

    WANG Wei-jiang; ZHOU Jin-yun; XIAO Wan-neng

    2006-01-01

    An all-optical diode behavior that uses a nonlinear one-dimensional photonic crystal (NPC) with a defect Kerr medium is numerically simulated by the use of a nonlinear finite-difference time-domain (NFDTD) method.The numerical results show that for an incident pulse with appropriate intensity and temporal width,the transmittance can be several times greater in one direction of NPC than in the opposite direction at the pulse carrier frequency. This behaves like an all-optical diode and has promising applications in some areas such as optical isolation and all-optical processing.The ways to obtain low threshold of pulse field strength to realize an all-optical diode are also analyzed in detail.

  7. High confinement, high yield Si3N4 waveguides for nonlinear optical applications

    NARCIS (Netherlands)

    Epping, J.P.; Hoekman, M.; Mateman, R.; Leinse, A.; Heideman, R.G.; Rees, van A.; Slot, van der P.J.M.; Lee, C.J.; Boller, K-J.

    2015-01-01

    In this paper we present a novel fabrication technique for silicon nitride (Si3N4) waveguides with a thickness of up to 900 nm, which are suitable for nonlinear optical applications. The fabrication method is based on etching trenches in thermally oxidized silicon and filling the trenches with Si3N4

  8. Proof of Concept for an Ultrasensitive Technique to Detect and Localize Sources of Elastic Nonlinearity Using Phononic Crystals

    Science.gov (United States)

    Miniaci, M.; Gliozzi, A. S.; Morvan, B.; Krushynska, A.; Bosia, F.; Scalerandi, M.; Pugno, N. M.

    2017-05-01

    The appearance of nonlinear effects in elastic wave propagation is one of the most reliable and sensitive indicators of the onset of material damage. However, these effects are usually very small and can be detected only using cumbersome digital signal processing techniques. Here, we propose and experimentally validate an alternative approach, using the filtering and focusing properties of phononic crystals to naturally select and reflect the higher harmonics generated by nonlinear effects, enabling the realization of time-reversal procedures for nonlinear elastic source detection. The proposed device demonstrates its potential as an efficient, compact, portable, passive apparatus for nonlinear elastic wave sensing and damage detection.

  9. Nonreciprocal transmission in a nonlinear photonic-crystal Fano structure with broken symmetry

    DEFF Research Database (Denmark)

    Yu, Yi; Chen, Yaohui; Hu, Hao;

    2015-01-01

    Nanostructures that feature nonreciprocal light trans- mission are highly desirable building blocks for realizing photonic integrated circuits. Here, a simple and ultracompact photonic-crystal structure, where a waveguide is coupled to a single nanocavity, is proposed and experimentally demon- st...... tunability. The nonlinearity of the device relies on ultrafast carrier dynamics, rather than the thermal effects usually considered, allowing the demonstration of nonreciprocal operation at a bit-rate of 10 Gbit s − 1 with a low energy consumption of 4.5 fJ bit − 1...

  10. Spectral transformations in the regime of pulse self-trapping in a nonlinear photonic crystal

    CERN Document Server

    Novitsky, Denis

    2011-01-01

    We consider interaction of a femtosecond light pulse with a one-dimensional photonic crystal with relaxing cubic nonlinearity in the regime of self-trapping. By use of numerical simulations, it is shown that, under certain conditions, the spectra of reflected and transmitted light possess the properties of narrow-band (quasi-monochromatic) or wide-band (continuum-like) radiation. It is remarkable that these spectral features appear due to a significant frequency shift and occur inside a photonic band gap of the structure under investigation.

  11. NONLINEAR OPTICAL FREQUENCY CONVERTER OF LASER RADIATION ON THE LBO TYPE I CRYSTALS

    Directory of Open Access Journals (Sweden)

    N. V. Kondratyuk

    2014-01-01

    Full Text Available Describes nonlinear optical frequency converter of laser radiation based on the two LBO type I crystals allowing to receive pulses of radiation at three wavelengths of 1064 nm, 532 nm and 355 nm with an adjustable pulse energy. For fine adjustment of the output pulse energy used two dual phase plates that change the orientation of the plane of polarization of the two waves in cascade third harmonic generation. Measured the efficiency of the generation of harmonics of the intensity of radiation at 1064 nm.

  12. Fiber-to-fiber nonlinear coupling via a nematic liquid crystal

    Science.gov (United States)

    Nyushkov, B. N.; Trashkeev, S. I.; Ivanenko, A. V.; Kolker, D. B.; Purtov, P. A.

    2017-01-01

    Nonlinear optical coupling between two single-mode fibers terminated coaxially in a nematic liquid crystal (NLC) was explored for the first time. Light-induced reorientation of nematic molecules can result in the stable self-collimation of light transmitted through the gap between fibers. Thus, high coupling efficiency can be achieved despite large fiber spacing. We demonstrated a coupling efficiency of up to ∼0.7, achieved with spacing equal to four diffraction lengths. This feature opens up possibilities for the development of novel in-line fiber-optic elements based on NLCs. For instance, a polarization controller was proposed and considered.

  13. Optical nonlinearities in GaSe and InSe crystals upon laser excitation

    Science.gov (United States)

    Kyazym-zade, A. G.; Salmanov, V. M.; Guseinov, A. G.; Gasanova, L. G.; Mamedov, R. M.

    2014-04-01

    The nonlinear absorption of light and its temporal evolution in the vicinity of exciton resonance in layered GaSe and InSe crystals under high optical excitation have been experimentally investigated. The decisive factor for the observed temporal dependence of the absorption coefficient and its dependence on the excitation intensity is screening excitons by nonequilibrium-carrier plasma. It is shown that the increase in the transmittance in the absorption-band edge in GaSe with a simultaneous blue shift of the band edge is caused by filling the energy bands under high optical excitation.

  14. Flat super-continuum generation based on normal dispersion nonlinear photonic crystal fibre

    DEFF Research Database (Denmark)

    Chow, K.K.; Takushima, Y.; Lin, C.

    2006-01-01

    Flat super-continuum generation spanning over the whole telecommunication band using a passively modelocked fibre laser source at 1550 nm together with a dispersion-flattened nonlinear photoinc crystal fibre is demonstrated. Since the pulses propagate in the normal dispersion regime of the fibre...... only, linear frequency chirp is induced by self-phase modulation which leads to a flat super-continuum. By launching the compressed 170 fs modelocked pulses with an average power of 10 mW into the fibre, super-continuum over 185 nm with less than 5 dB fluctuation is obtained from the all...

  15. Temperature-Dependent Sellmeier Equations of IR Nonlinear Optical Crystal BaGa4Se7

    Directory of Open Access Journals (Sweden)

    Naixia Zhai

    2017-02-01

    Full Text Available The thermal dependent principal refractive indices of a new promising IR nonlinear optical crystal BaGa4Se7 at wavelengths of 0.546, 0.5806, 0.644, 0.7065, 1.530, 1.970, and 2.325μm were measured by using the vertical incidence method within the temperature range from 25 to 150 °C. We derived equations of thermal refractive index coefficients as a function of wavelength that could be used to calculate the principal thermal refractive indices at different wavelengths. The temperature-dependent Sellmeier equations were also obtained and used to calculate the phase matching angles for the optical parametric process of BaGa4Se7 crystal at different temperatures.

  16. Compact engineering of path-entangled sources from a monolithic quadratic nonlinear photonic crystal

    CERN Document Server

    Jin, H; Luo, X W; Leng, H Y; Gong, Y X; Zhu, S N

    2013-01-01

    Photonic entangled states lie at the heart of quantum science for the demonstrations of quantum mechanics foundations and supply as a key resource for approaching various quantum technologies. An integrated realization of such states will certainly guarantee a high-degree of entanglement and improve the performance like portability, stability and miniaturization, hence becomes an inevitable tendency towards the integrated quantum optics. Here, we report the compact realization of steerable photonic path-entangled states from a monolithic quadratic nonlinear photonic crystal. The crystal acts as an inherent beam splitter to distribute photons into coherent spatial modes, producing the heralded single-photon even appealing beamlike two-photon path-entanglement, wherein the entanglement is characterized by quantum spatial beatings. Such multifunctional entangled source can be further extended to high-dimensional fashion and multi-photon level as well as involved with other degrees of freedom, which paves a desir...

  17. Structural, thermal, optical and nonlinear optical properties of ethylenediaminium picrate single crystals

    Science.gov (United States)

    Indumathi, C.; T. C., Sabari Girisun; Anitha, K.; Alfred Cecil Raj, S.

    2017-07-01

    A new organic optical limiting material, ethylenediaminium picrate (EDAPA) was synthesized through acid base reaction and grown as single crystals by solvent evaporation method. Single crystal XRD analysis showed that EDAPA crystallizes in orthorhombic system with Cmca as space group. The formation of charge transfer complex during the reaction of ethylenediamine and picric acid was strongly evident through the recorded Fourier Transform Infra Red (FTIR), Raman and Nuclear Magnetic Resonance (NMR) spectrum. Thermal (TG-DTA and DSC) curves indicated that the material possesses high thermal stability with decomposition temperature at 243 °C. Optical (UV-Visible-NIR) analysis showed that the grown crystal was found to be transparent in the entire visible and NIR region. Z-scan studies with intense short pulse (532 nm, 5 ns, 100 μJ) excitations, revealed that EDAPA exhibited two photon absorption behaviour and the nonlinear absorption coefficient was found to be two orders of magnitude higher than some of the known optical limiter like Cu nano glasses. EDAPA exhibited a strong optical limiting action with low limiting threshold which make them a potential candidate for eye and photosensitive component protection against intense short pulse lasers.

  18. Generation of broadband spontaneous parametric fluorescence using multiple bulk nonlinear crystals

    CERN Document Server

    Okano, Masayuki; Tanaka, Akira; Subashchandran, Shanthi; Takeuchi, Shigeki; 10.1364/OE.20.013977

    2012-01-01

    We propose a novel method for generating broadband spontaneous parametric fluorescence by using a set of bulk nonlinear crystals (NLCs). We also demonstrate this scheme experimentally. Our method employs a superposition of spontaneous parametric fluorescence spectra generated using multiple bulk NLCs. A typical bandwidth of 160 nm (73 THz) with a degenerate wavelength of 808 nm was achieved using two beta-barium-borate (BBO) crystals, whereas a typical bandwidth of 75 nm (34 THz) was realized using a single BBO crystal. We also observed coincidence counts of generated photon pairs in a non-collinear configuration. The bandwidth could be further broadened by increasing the number of NLCs. Our demonstration suggests that a set of four BBO crystals could realize a bandwidth of approximately 215 nm (100 THz).We also discuss the stability of Hong-Ou-Mandel two-photon interference between the parametric fluorescence generated by this scheme. Our simple scheme is easy to implement with conventional NLCs and does not...

  19. Generation of broadband spontaneous parametric fluorescence using multiple bulk nonlinear crystals.

    Science.gov (United States)

    Okano, Masayuki; Okamoto, Ryo; Tanaka, Akira; Subashchandran, Shanthi; Takeuchi, Shigeki

    2012-06-18

    We propose a novel method for generating broadband spontaneous parametric fluorescence by using a set of bulk nonlinear crystals (NLCs). We also demonstrate this scheme experimentally. Our method employs a superposition of spontaneous parametric fluorescence spectra generated using multiple bulk NLCs. A typical bandwidth of 160 nm (73 THz) with a degenerate wavelength of 808 nm was achieved using two β-barium-borate (BBO) crystals, whereas a typical bandwidth of 75 nm (34 THz) was realized using a single BBO crystal. We also observed coincidence counts of generated photon pairs in a non-collinear configuration. The bandwidth could be further broadened by increasing the number of NLCs. Our demonstration suggests that a set of four BBO crystals could realize a bandwidth of approximately 215 nm (100 THz). We also discuss the stability of Hong-Ou-Mandel two-photon interference between the parametric fluorescence generated by this scheme. Our simple scheme is easy to implement with conventional NLCs and does not require special devices.

  20. Growth, spectral, linear and nonlinear optical characteristics of an efficient semiorganic acentric crystal: L-valinium L-valine chloride

    Energy Technology Data Exchange (ETDEWEB)

    Nageshwari, M.; Jayaprakash, P.; Kumari, C. Rathika Thaya [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604407, Tamil Nadu (India); Vinitha, G. [Department of Physics, School of Advanced Sciences, VIT Chennai, 600127 Tamil Nadu (India); Caroline, M. Lydia, E-mail: lydiacaroline2006@yahoo.co.in [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604407, Tamil Nadu (India)

    2017-04-15

    An efficient nonlinear optical semiorganic material L-valinium L-valine chloride (LVVCl) was synthesized and grown-up by means of slow evaporation process. Single crystal XRD evince that LVVCl corresponds to monoclinic system having acentric space group P2{sub 1}. The diverse functional groups existing in LVVCl were discovered with FTIR spectral investigation. The UV-Visible and photoluminescence spectrum discloses the optical and electronic properties respectively for the grown crystal. Several optical properties specifically extinction coefficient, reflectance, linear refractive index, electrical and optical conductivity were also determined. The SEM analysis was also carried out and it portrayed the surface morphology of LVVCl. The calculated value of laser damage threshold was 2.59 GW/cm{sup 2}. The mechanical and dielectric property of LVVCl was investigated employing microhardness and dielectric studies. The second and third order nonlinear optical characteristics of LVVCl was characterized utilizing Kurtz Perry and Z scan technique respectively clearly suggest its suitability in the domain of optics and photonics. - Graphical abstract: Good quality transparent single crystals of L-valinium L-valine chloride single crystal was grown by slow evaporation technique. The grown crystals were analyzed using different instrumentation methods to check its usefulness for the device fabrication. The determination of nonlinear refractive index (n{sub 2}), absorption coefficient (β) and third order nonlinear susceptibility was determined by Z scan technique, highlighted that LVVCl can serve as a promising candidate for opto electronic and nonlinear optical applications.

  1. Determination of nonlinear absorption and refraction in direct and indirect band gap crystals by Z-scan method.

    Science.gov (United States)

    Gaur, Poonam; Sharma, Dimple; Singh, Nageshwar; Malik, B P; Gaur, Arun

    2012-11-01

    A systematic investigation on nonlinear optical properties such as three photon absorption (3PA) wavelength dependent of Kerr type nonlinear refraction in direct and indirect band gap crystals has been reported in the present work. The Z-scan measurements are recorded for both ZnO and CdI(2) with femtosecond laser pulses while the wavelength dependent of the Kerr nonlinearity are in agreement with a two band model. The wavelength dependence of the 3PA is determined by [(3E(photon)/E(g))-1](5/2)[(3E(photon)/E(g))](-9) in the case of direct band gap crystal and [(3E(photon)±ℏΩ/E(g))-1](5/2)[(3E(photon)±ℏΩ/E(g))](-9) in the case of indirect band gap crystal. In the present investigation the value of 3PA in the case of indirect band gap crystal is lower than the direct band gap crystal which is due to the phonon assisted transition. The materials of large band gap with optical nonlinearity and fast response speed should be dominating factor for further photonic devices such as optical limiters, optical switches and optical modulators. The higher order nonlinear optical effects have also been determined in the present study. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Theory of nonlinear elasticity, stress-induced relaxation, and dynamic yielding in dense fluids of hard nonspherical colloids.

    Science.gov (United States)

    Zhang, Rui; Schweizer, Kenneth S

    2012-04-21

    We generalize the microscopic naïve mode coupling and nonlinear Langevin equation theories of the coupled translation-rotation dynamics of dense suspensions of uniaxial colloids to treat the effect of applied stress on shear elasticity, cooperative cage escape, structural relaxation, and dynamic and static yielding. The key concept is a stress-dependent dynamic free energy surface that quantifies the center-of-mass force and torque on a moving colloid. The consequences of variable particle aspect ratio and volume fraction, and the role of plastic versus double glasses, are established in the context of dense, glass-forming suspensions of hard-core dicolloids. For low aspect ratios, the theory provides a microscopic basis for the recently observed phenomenon of double yielding as a consequence of stress-driven sequential unlocking of caging constraints via reduction of the distinct entropic barriers associated with the rotational and translational degrees of freedom. The existence, and breadth in volume fraction, of the double yielding phenomena is predicted to generally depend on both the degree of particle anisotropy and experimental probing frequency, and as a consequence typically occurs only over a window of (high) volume fractions where there is strong decoupling of rotational and translational activated relaxation. At high enough concentrations, a return to single yielding is predicted. For large aspect ratio dicolloids, rotation and translation are always strongly coupled in the activated barrier hopping event, and hence for all stresses only a single yielding process is predicted.

  3. Light yield of an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin

    Science.gov (United States)

    Liu, Jing; Yamashita, Masaki; Soma, Arun Kumar

    2017-01-01

    A light yield of 20 . 4 +/- 0 . 8 photoelectrons/keV was achieved with an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin. This is by far the largest in the world achieved with CsI crystals. An energy threshold that is several times lower than the current dark matter experiments utilizing CsI(Tl) crystals may be achievable using this technique. Together with novel CsI crystal purification methods, the technique may be used to improve the sensitivities of dark matter and coherent elastic neutrino-nucleus scattering experiments. Also measured were the scintillation light decay constants of the undoped CsI crystal at both room temperature and 77 Kelvin. The results are consistent with those in the literature. This work was supported by NSF PHY-1506036, USA and Grant-in-Aid (B) Project No. 26800122, MEXT, Japan.

  4. Synthesis, growth, and structural, optical, mechanical, electrical properties of a new inorganic nonlinear optical crystal: Sodium manganese tetrachloride (SMTC

    Directory of Open Access Journals (Sweden)

    M. Packiya raj

    2017-01-01

    Full Text Available A new inorganic nonlinear optical single crystal of sodium manganese tetrachloride (SMTC has been successfully grown from aqueous solution using the slow evaporation technique at room temperature. The crystals obtained using the aforementioned method were characterized using different techniques. The crystalline nature of the as-grown crystal of SMTC was analyzed using powder X-ray diffraction. Single-crystal X-ray diffraction revealed that the crystal belongs to an orthorhombic system with non-centrosymmetric space group Pbam. The optical transmission study of the SMTC crystal revealed high transmittance in the entire UV–vis region, and the lower cut-off wavelength was determined to be 240 nm. The mechanical strength of the as-grown crystal was estimated using the Vickers microhardness test. The second harmonic generation (SHG efficiency of the crystal was measured using Kurtz's powder technique, which indicated that the crystal has a nonlinear optical (NLO efficiency that is 1.32 times greater than that of KDP. The dielectric constant and dielectric loss of the compound were measured at different temperatures with varying frequencies. The photoconductivity study confirmed that the title compound possesses a negative photoconducting nature. The growth mechanism and surface features of the as-grown crystals were investigated using chemical etching analysis.

  5. Enhancing the Long-Term Yield Competitiveness of a Semiconductor Manufacturing Factory Using a Multiobjective Fuzzy Nonlinear Programming Approach

    Directory of Open Access Journals (Sweden)

    Toly Chen

    2013-01-01

    Full Text Available This study proposes a multiobjective fuzzy nonlinear programming (MOFNP approach to enhance the long-term yield competitiveness of a semiconductor manufacturing factory. By modeling the long-term competitiveness of every product in a semiconductor manufacturing plant with the fuzzy correlation coefficient (FCC between time and instantaneous competitiveness, the proposed model considers the various viewpoints when interpreting the overall competitiveness of the semiconductor manufacturing plant in the long-term. All noninferior solutions of the MOFNP solutions are then derived using a systematic procedure. A real example is employed to illustrate the applicability of the proposed methodology.

  6. Experimental observation of long-wavelength dispersive wave generation induced by self-defocusing nonlinearity in BBO crystal

    CERN Document Server

    Zhou, Binbin

    2015-01-01

    We experimentally observe long-wavelength dispersive waves generation in a BBO crystal. A soliton was formed in normal GVD regime of the crystal by a self-defocusing and negative nonlinearity through phase-mismatched quatradic interaction. Strong temporal pulse compression confirmed the formation of soliton during the pulse propagation inside the crystal. Significant dispersive wave radiation was measured in the anomalous GVD regime of the BBO crystal. With the pump wavelengths from 1.24 to 1.4 $\\mu$m, tunable dispersive waves are generated around 1.9 to 2.2 $\\mu$m. The observed dispersive wave generation is well understood by simulations.

  7. Optimization of highly nonlinear dispersion-flattened photonic crystal fiber for supercontinuum generation

    Institute of Scientific and Technical Information of China (English)

    Zhang Ya-Ni

    2013-01-01

    A simple type of photonic crystal fiber (PCF) for supercontinuum generation is proposed for the first time.The proposed PCF is composed of a solid silica core and a cladding with square lattice uniform elliptical air holes,which offers not only a large nonlinear coefficient but also a high birefringence and low leakage losses.The PCF with nonlinear coefficient as large as 46 W-1 · km-1 at the wavelength of 1.55 μm and a total dispersion as low as ±2.5 ps.nm-1 · km-1 over an ultra-broad waveband range of the S-C-L band (wavelength from 1.46 μm to 1.625 μm) is optimized by adjusting its structure parameter,such as the lattice constant A,the air-filling fraction f,and the air-hole ellipticity η.The novel PCF with ultra-flattened dispersion,highly nonlinear coefficient,and nearly zero negative dispersion slope will offer a possibility of efficient super-continuum generation in telecommunication windows using a few ps pulses.

  8. A comparative study on dual colour soft aperture cascaded second-order mode-locking with different nonlinear optical crystals

    Indian Academy of Sciences (India)

    Shyamal Mondal; Satya Pratap Singh; Sourabh Mukhopadhyay; Aditya Date; Kamal Hussain; Shouvik Mukherjee; Prasanta Kumar Datta

    2014-02-01

    A comparative study in terms of optimized output power and stability is made on cascaded second-order nonlinear optical mode-locking with KTP, BBO and LBO crystals for both 1064 nm and 532 nm. Large nonlinear optical phase shift achieved in a non-phase-matched second harmonic generating crystal, is transformed into amplitude modulation through soft aperturing the nonlinear cavity mode variation at the laser gain medium to mode-lock a Nd:YVO4 laser. The laser delivers stable dual wavelength cw mode-locked pulse train with pulse duration 10.3 ps and average power of 1.84 W and 255 mW at 1064 nm and 532 nm respectively for the optimum performance in type-II KTP crystal. The exceptional stability achieved with KTP is accounted by simulating the mode-size variation with phase mismatch.

  9. Investigations on the electrical, thermal and optical properties of the nonlinear optical allylthiourea mercury chloride single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sreekanth, G. [Department of Physics, St. Thomas College Pala, Kottayam 686574, Kerala (India); Chandralingam, S. [Department of Physics, Jawaharlal Nehru Technological University, Hyderabad 500085 (India); Philip, Jacob; Jayalakshmy, M.S. [Department of instrumentation, Cochin University of Science and Technology, Cochin, Kerala (India); Philip, Reji; Sridharan, Kishore [Raman research institute, Bangalore, Karnataka 560080 (India); Santhosh Kumar, R. [Department of Physics, St. George' s College Aruvithura, Kottayam 686122, Kerala (India); Joseph, Ginson P., E-mail: ginsonpj@gmail.com [Department of Physics, St. Thomas College Pala, Kottayam 686574, Kerala (India)

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► The single crystals of dimension 10 × 5 × 5 mm{sup 3} of allylthiourea mercury chloride are synthesized using slow evaporation technique. ► The bandgap of allylthiourea mercury chloride crystal is found to be about 3.18 eV. ► The optical nonlinearity of the crystal sample are studied using the open aperture Z-scan technique employing a nanosecond laser at 532 nm, and three photon absorption effect has been found. ► An improved photo pyroelectric is used to find the thermal parameters of the crystal. ► The piezoelectric charge coefficient is determined. -- Abstract: Single crystals of dimension 10 × 5 × 5 mm{sup 3} of allylthiourea mercury chloride were synthesized from aqueous solution using slow evaporation technique at ambient temperature. The grown crystals are confirmed by elemental analysis. The band gap of Allylthiourea mercury chloride crystal was found to be about 3.18 eV. The optical nonlinearity of the crystal sample was studied using the open aperture Z-scan technique employing a nanosecond laser at 532 nm, and a three-photon absorption effect has been found. The electrical properties such as dielectric constant, dielectric loss and ac conductivity of the sample were carried out by Agillent E 4980 A LCR meter at different temperatures. An improved photopyroelectric technique was used to find the thermal parameters of the crystal. The piezo electric charge coefficient is also determined.

  10. Crystal studies, vibrational spectra and non-linear optical properties of L-histidine chloride monohydrate.

    Science.gov (United States)

    Ben Ahmed, A; Feki, H; Abid, Y; Boughzala, H; Minot, C

    2010-01-01

    This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a non-linear optical material L-histidine chloride monohydrate. Due to the lack of sufficiently precise information on geometric parameters available in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine chloride monohydrate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro-symmetric space group P2(1)2(1)2(1) of orthorhombic system. IR spectrum has been recorded in the range [400-4000 cm(-1)]. All the experimental vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our calculations. The optimized geometric bond lengths and bond angles obtained by using DFT//B3LYP/6-31G (d) method show a good agreement with the experimental data. The calculated vibrational spectra are in well agreement with the experimental one. To investigate microscopic second-order non-linear optical NLO behavior of the examined complex, the electric dipole mu, the polarizability alpha and the hyperpolarizability beta were computed using DFT//B3LYP/6-31G (d) method. The time-dependent density functional theory (TD-DFT) was employed to descript the molecular electron structure of the title compound using the B3LYP/6-31G (d) method. According to our calculations, L-histidine chloride monohydrate exhibits non-zero beta value revealing microscopic second-order NLO behavior. Copyright 2009 Elsevier B.V. All rights reserved.

  11. Crystal studies, vibrational spectra and non-linear optical properties of L-histidine chloride monohydrate

    Science.gov (United States)

    Ahmed, A. Ben; Feki, H.; Abid, Y.; Boughzala, H.; Minot, C.

    2010-01-01

    This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a non-linear optical material L-histidine chloride monohydrate. Due to the lack of sufficiently precise information on geometric parameters available in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine chloride monohydrate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro-symmetric space group P2 12 12 1 of orthorhombic system. IR spectrum has been recorded in the range [400-4000 cm -1]. All the experimental vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our calculations. The optimized geometric bond lengths and bond angles obtained by using DFT//B3LYP/6-31G (d) method show a good agreement with the experimental data. The calculated vibrational spectra are in well agreement with the experimental one. To investigate microscopic second-order non-linear optical NLO behavior of the examined complex, the electric dipole μ, the polarizability α and the hyperpolarizability β were computed using DFT//B3LYP/6-31G (d) method. The time-dependent density functional theory (TD-DFT) was employed to descript the molecular electron structure of the title compound using the B3LYP/6-31G (d) method. According to our calculations, L-histidine chloride monohydrate exhibits non-zero β value revealing microscopic second-order NLO behavior.

  12. Investigation of the linear and second-order nonlinear optical properties of molecular crystals within the local field theory.

    Science.gov (United States)

    Seidler, Tomasz; Stadnicka, Katarzyna; Champagne, Benoît

    2013-09-21

    In this paper it is shown that modest calculations combining first principles evaluations of the molecular properties with electrostatic interaction schemes to account for the crystal environment effects are reliable for predicting and interpreting the experimentally measured electric linear and second-order nonlinear optical susceptibilities of molecular crystals within the experimental error bars. This is illustrated by considering two molecular crystals, namely: 2-methyl-4-nitroaniline and 4-(N,N-dimethylamino)-3-acetamidonitrobenzene. Three types of surrounding effects should be accounted for (i) the polarization due to the surrounding molecules, described here by static electric fields originating from their electric dipoles or charge distributions, (ii) the intermolecular interactions, which affect the geometry and particularly the molecular conformation, and (iii) the screening of the external electric field by the constitutive molecules. This study further highlights the role of electron correlation on the linear and nonlinear responses of molecular crystals and the challenge of describing frequency dispersion.

  13. Luminescence and light yield of (Gd2Y)(Ga3Al2)O12:Pr3+ single crystal scintillators

    Science.gov (United States)

    Lertloypanyachai, Prapon; Pathumrangsan, Nichakorn; Sreebunpeng, Krittiya; Pattanaboonmee, Nakarin; Chewpraditkul, Weerapong; Yoshikawa, Akira; Kamada, Kei; Nikl, Martin

    2017-06-01

    Praseodymium-doped (Gd2Y)(Ga3Al2)O12 (GYGAG: Pr) single crystals are grown by the micro-pulling down method with different Pr concentrations. The energy transfer process between Pr3+ and Gd3+ is investigated by photoluminescence excitation (PLE) and emission (PL) spectra measurements. Photoelectron yield measurements are carried out using photomultiplier. At 662 keV γ-rays, photoelectron yield of 2520 phe/MeV obtained for the GYGAG: Pr (0.01%) sample is larger than that of 1810 phe/MeV obtained for BGO crystal. Light yield degradation for the GYGAG: Pr scintillators is presumably due to the energy transfer from 5d state of Pr3+ to 4f state of Gd3+ together with the concentration quenching in the Gd3+-sublattice.

  14. The anisotropic Kerr nonlinear refractive index of the beta-barium borate (β-BaB2O4) nonlinear crystal

    DEFF Research Database (Denmark)

    Bache, Morten; Guo, Hairun; Zhou, Binbin;

    2013-01-01

    We study the anisotropic nature of the Kerr nonlinear response in a beta-barium borate (β-BaB2O4, BBO) nonlinear crystal. The focus is on determining the relevant χ(3) cubic tensor components that affect interaction of type I cascaded second-harmonic generation. Various experiments...... a complete list that we propose as reference of the four major cubic tensor components in BBO. We finally discuss the impact of using the cubic anisotropic response in ultrafast cascading experiments in BBO....

  15. Nonlinear photonic crystal fiber with a structured multi-component glass core for four-wave mixing and supercontinuum generation.

    Science.gov (United States)

    Tombelaine, Vincent; Labruyère, Alexis; Kobelke, Jens; Schuster, Kay; Reichel, Volker; Leproux, Philippe; Couderc, Vincent; Jamier, Raphaël; Bartelt, Hartmut

    2009-08-31

    We report about a new type of nonlinear photonic crystal fibers allowing broadband four-wave mixing and supercontinuum generation. The microstructured optical fiber has a structured core consisting of a rod of highly nonlinear glass material inserted in a silica tube. This particular structure enables four wave mixing processes with very large frequency detuning (>135 THz), which permitted the generation of a wide supercontinuum spectrum extending over 1650 nm after 2.15 m of propagation length. The comparison with results obtained from germanium-doped holey fibers confirms the important role of the rod material properties regarding nonlinear process and dispersion.

  16. Design of photonic crystal fibers with highly nonlinear glasses for four-wave-mixing based telecom applications.

    Science.gov (United States)

    Kanka, Jiri

    2008-12-08

    A fully-vectorial mode solver based on the finite element method is employed in a combination with the downhill simplex method the dispersion optimization of photonic crystal fibers made from highly nonlinear glasses. The nonlinear fibers are designed for telecom applications such as parametric amplification, wavelength conversion, ultra-fast switching and regeneration of optical signals. The optimization is carried in terms of the zero dispersion wavelength, dispersion magnitude and nonlinear coefficient and confinement loss in the wavelength range around 1.55 microm. We restrict our work to the index-guiding fiber structures a small number of hexagonally arrayed air holes.

  17. Subpicosecond pulse compression in nonlinear photonic crystal waveguides based on the formation of high-order optical solitons

    Institute of Scientific and Technical Information of China (English)

    Chen Xiong-Wen; Lin Xu-Sheng; Lan Sheng

    2005-01-01

    We investigate by numerical simulation the compression of subpicosecond pulses in two-dimensional nonlinear photonic crystal (PC) waveguides. The compression originates from the generation of high-order optical solitons through the interplay of the huge group-velocity dispersion and the enhanced self-phase modulation in nonlinear PC waveguides.Both the formation of Bragg grating solitons and gap solitons can lead to efficient pulse compression. The compression factors under different excitation power densities and the optimum length for subpicosecond pulse compression have been determined. As a compressor, the total length of the nonlinear PC waveguide is only ten micrometres and therefore can be easily incorporated into PC integrated circuits.

  18. Growth, structural, optical, thermal and mechanical properties of cytosinium hydrogen selenite: A novel nonlinear optical single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Jaikumar, P. [PG & Research Department of Physics, National College (Autonomous), Tiruchirappalli, 620 001 Tamil Nadu (India); Sathiskumar, S. [Crystal Growth Laboratory, Department of Physics, Periyar EVR College (Autonomous), Tiruchirappalli, 620 023 Tamil Nadu (India); Balakrishnan, T., E-mail: balacrystalgrowth@gmail.com [Crystal Growth Laboratory, Department of Physics, Periyar EVR College (Autonomous), Tiruchirappalli, 620 023 Tamil Nadu (India); Ramamurthi, K. [Crystal Growth & Thin Film laboratory, Department of Physics & Nanotechnology, SRM University, Kattankulathur, 603 203 Kancheepuram, Tamil Nadu (India)

    2016-06-15

    Highlights: • Growth of bulk single crystals of cytosinium hydrogen selenite (CHS) is reported. • Dielectric constant of CHS is measured as a function of Frequency and temperature. • Lower cut off value of UV–vis-NIR spectrum of CHS crystal is observed at 210 nm. • Meyer’s index value of CHS crystal calculated identifies it as a soft material. • Powder SHG efficiency of CHS is about 1.5 times that of KDP crystal. - Abstract: A novel nonlinear optical single crystal of cytosinium hydrogen selenite was grown from aqueous solution of cytosinium hydrogen selenite by slow solvent evaporation method at room temperature. The structural properties of grown crystal have been studied by single crystal and powder X-ray diffraction analysis. Presence of various functional groups was identified from Fourier transform infrared spectroscopy. The optical transmittance and absorbance spectra were recorded by UV–vis-NIR spectrometer and the grown crystal possesses good transparency in the entire visible region. The dielectric constant and dielectric loss of the crystal were calculated as a function of frequency at different temperatures. The mechanical strength of the cytosinium hydrogen selenite crystal was estimated using Vicker’s microhardness tester. Etch patterns of the cytosinium hydrogen selenite crystal were obtained using distilled water as etchant for different etching time. Second harmonic generation efficiency tested using Nd:YAG laser is about 1.5 times that of KDP.

  19. Investigation of gamma radiation effect on chemical properties and surface morphology of some nonlinear optical (NLO) single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ahlam, M.A., E-mail: omaymn771@yahoo.com [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka (India); Ravishankar, M.N. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka (India); Vijayan, N. [Materials Characterization Division, National Physical Laboratory, New Delhi 110 012 (India); Govindaraj, G. [Department of Physics, Pondicherry University, Pondicherry 605 014 (India); Siddaramaiah [Department of Polymer and Technology, Sri Jayachamarajendra College of Engineering, Mysore 570 006 (India); Gnana Prakash, A.P., E-mail: gnanaprakash@physics.uni-mysore.ac.in [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka (India)

    2012-05-01

    The effect of Co-60 gamma irradiation on L-alanine cadmium chloride (LACC), L-alanine doped potassium dihydrogen orthophosphate (KDP) and L-arginine doped KDP nonlinear optical (NLO) single crystals were studied in doses ranging from 100 krad to 6 Mrad. The crystals were grown by slow evaporation method at room temperature. The effects of gamma irradiation on the chemical, surface morphology, DC electrical conductivity, thermal and mechanical properties of the grown crystals have been studied. The functional groups of unirradiated and irradiated crystals have been identified and confirmed by Fourier transform infrared (FTIR) studies. Scanning electron microscopy (SEM) of irradiated crystals shows some morphological changes in the crystals. The dc conductivity of LACC and L-alanine doped KDP crystals were found to increase with increase in radiation dose whereas in case of L-arginine doped KDP crystals, the dc conductivity was found to decrease with increase in radiation dose. Differential scanning calorimetry (DSC) thermograms reveals that there is no significant change in the melting point of the crystals after irradiation and the crystals does not decompose as a result of irradiation. The mechanical behavior of both unirradiated and irradiated crystals is explained with the indentation effects using Vicker's microhardness tester. The Vicker's hardness number H{sub V} and Mayer's index 'n' has been estimated and confirms that LACC belong to the hard materials.

  20. Investigation of gamma radiation effect on chemical properties and surface morphology of some nonlinear optical (NLO) single crystals

    Science.gov (United States)

    Ahlam, M. A.; Ravishankar, M. N.; Vijayan, N.; Govindaraj, G.; Siddaramaiah; Gnana Prakash, A. P.

    2012-05-01

    The effect of Co-60 gamma irradiation on L-alanine cadmium chloride (LACC), L-alanine doped potassium dihydrogen orthophosphate (KDP) and L-arginine doped KDP nonlinear optical (NLO) single crystals were studied in doses ranging from 100 krad to 6 Mrad. The crystals were grown by slow evaporation method at room temperature. The effects of gamma irradiation on the chemical, surface morphology, DC electrical conductivity, thermal and mechanical properties of the grown crystals have been studied. The functional groups of unirradiated and irradiated crystals have been identified and confirmed by Fourier transform infrared (FTIR) studies. Scanning electron microscopy (SEM) of irradiated crystals shows some morphological changes in the crystals. The dc conductivity of LACC and L-alanine doped KDP crystals were found to increase with increase in radiation dose whereas in case of L-arginine doped KDP crystals, the dc conductivity was found to decrease with increase in radiation dose. Differential scanning calorimetry (DSC) thermograms reveals that there is no significant change in the melting point of the crystals after irradiation and the crystals does not decompose as a result of irradiation. The mechanical behavior of both unirradiated and irradiated crystals is explained with the indentation effects using Vicker's microhardness tester. The Vicker's hardness number HV and Mayer's index 'n' has been estimated and confirms that LACC belong to the hard materials.

  1. Design and optimization of highly nonlinear low-dispersion crystal fiber with high birefringence for four-wave mixing.

    Science.gov (United States)

    Zhang, Ya-Ni; Ren, Li-Yong; Gong, Yong-Kang; Li, Xiao-Hui; Wang, Lei-Ran; Sun, Chuan-Dong

    2010-06-01

    We have proposed a novel type of photonic crystal fiber (PCF) with low dispersion and high nonlinearity for four-wave mixing. This type of fiber is composed of a solid silica core and a cladding with a squeezed hexagonal lattice elliptical airhole along the fiber length. Its dispersion and nonlinearity coefficient are investigated simultaneously by using the full vectorial finite element method. Numerical results show that the proposed highly nonlinear low-dispersion fiber has a total dispersion as low as +/-2.5 ps nm(-1) km(-1) over an ultrabroad wavelength range from 1.43 to 1.8 microm, and the corresponding nonlinearity coefficient and birefringence are about 150 W(-1) km(-1) and 2.5x10(-3) at 1.55 microm, respectively. The proposed PCF with low ultraflattened dispersion, high nonlinearity, and high birefringence can have important application in four-wave mixing.

  2. Growth and characterization of benzaldehyde 4-nitro phenyl hydrazone (BPH) single crystal: A proficient second order nonlinear optical material

    Science.gov (United States)

    Saravanan, M.; Abraham Rajasekar, S.

    2016-04-01

    The crystals (benzaldehyde 4-nitro phenyl hydrazone (BPH)) appropriate for NLO appliance were grown by the slow cooling method. The solubility and metastable zone width measurement of BPH specimen was studied. The material crystallizes in the monoclinic crystal system with noncentrosymmetric space group of Cc. The optical precision in the whole visible region was found to be excellent for non-linear optical claim. Excellence of the grown crystal is ascertained by the HRXRD and etching studies. Laser Damage Threshold and Photoluminescence studies designate that the grown crystal contains less imperfection. The mechanical behaviour of BPH sample at different temperatures was investigated to determine the hardness stability of the grown specimen. The piezoelectric temperament and the relative Second Harmonic Generation (for diverse particle sizes) of the material were also studied. The dielectric studies were executed at varied temperatures and frequencies to investigate the electrical properties. Photoconductivity measurement enumerates consummate of inducing dipoles due to strong incident radiation and also divulge the nonlinear behaviour of the material. The third order nonlinear optical properties of BPH crystals were deliberate by Z-scan method.

  3. Nonlinear wavelength conversion in photonic crystal fibers with three zero dispersion points

    CERN Document Server

    Stark, S P; Podlipensky, A; Russell, P St J

    2010-01-01

    In this theoretical study, we show that a simple endlessly single-mode photonic crystal fiber can be designed to yield, not just two, but three zero-dispersion wavelengths. The presence of a third dispersion zero creates a rich phase-matching topology, enabling enhanced control over the spectral locations of the four-wave-mixing and resonant-radiation bands emitted by solitons and short pulses. The greatly enhanced flexibility in the positioning of these bands has applications in wavelength conversion, supercontinuum generation and pair-photon sources for quantum optics.

  4. Nonlinear response and dynamical transitions in a phase-field crystal model for adsorbed overlayers

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, J A P [Departamento de Ciencias Exatas, Universidade Estadual do Sudoeste da Bahia, 45000-000 Vitoria da Conquista, BA (Brazil); Granato, E [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, 12245-970 Sao Jose dos Campos, SP (Brazil); Ying, S C; Ala-Nissila, T [Department of Physics, PO Box 1843, Brown University, Providence, RI 02912-1843 (United States); Achim, C V [Department of Applied Physics, Aalto University School of Science and Technology, PO Box 11000, FI-00076 Aalto, Espoo (Finland); Elder, K R, E-mail: Jorge@las.inpe.b [Department of Physics, Oakland University, Rochester, Michigan 48309-4487 (United States)

    2010-09-01

    The nonlinear response and sliding friction behavior of a phase-field crystal model for driven adsorbed atomic layers is determined numerically. The model describes the layer as a continuous density field coupled to the pinning potential of the substrate and under an external driving force. Dynamical equations which take into account both thermal fluctuations and inertial effects are used for numerical simulations of commensurate and incommensurate layers. At low temperatures, the velocity response of an initially commensurate layer shows hysteresis with dynamical melting and freezing transitions at different critical forces. The main features of the sliding friction behavior are similar to the results obtained previously from molecular dynamics simulations of particle models. However, the dynamical transitions correspond to nucleations of stripes rather than closed domains.

  5. Broadband wavelength converter based on four-wave mixing in a highly nonlinear photonic crystal fiber.

    Science.gov (United States)

    Zhang, Ailing; Demokan, M S

    2005-09-15

    We demonstrate a 10 Gbit/s nonreturn-to-zero wavelength converter based on four-wave mixing in a 20 m highly nonlinear photonic crystal fiber. The tunable wavelength conversion bandwidth (3 dB) is about 100 nm. The conversion efficiency is -16 dB when the pump power is 22.5 dBm. Phase modulation was not used to suppress the stimulated Brillouin scattering; thus the linewidth of the converted wavelength remained very narrow. The eye diagrams show that there is no additional noise during wavelength conversion. The measured power penalty at a 10(-9) bit-error-rate level is about 0.7 dB.

  6. Second-order nonlinearities and crystal structure of 2-methoxy-4 prime -nitro-(E)-stilbene

    Energy Technology Data Exchange (ETDEWEB)

    Grubbs, R.B.; Marder, S.R.; Perry, J.W.; Schaefer, W.P. (California Inst. of Tech., Pasadena (USA))

    Second-order nonlinear optical (NLO) properties of crystalline materials depend both on the magnitude of the molecular hyperpolarizability ({beta}) and on the orientation of the chromophores in the crystal lattice. To develop molecular structure-property relationships, it is important to measure accurate values of {beta} for many series of compounds. These values, which can be obtained by electric-field-induced second harmonic generation (EFISH) experiments, coupled with theoretical modeling will provide guidelines for the synthesis of new NLO materials. Recently Cheng et al. have examined the effect that variation of donor and acceptor strength has on {beta}, for various aromatic systems, including benzenes and stilbenes. In collaboration with Cheng, the authors are now studying the effect on the magnitude of {beta} of variation of the relative substitution position of the donor and acceptor in stilbenes.

  7. Contamination and Radiation Effects on Nonlinear Crystals for Space Laser Systems

    Science.gov (United States)

    Abdeldayem, Hossain A.; Dowdye, Edward; Jamison, Tracee; Canham, John; Jaeger, Todd

    2005-01-01

    Space Lasers are vital tools for NASA s space missions and military applications. Although, lasers are highly reliable on the ground, several past space laser missions proved to be short-lived and unreliable. In this communication, we are shedding more light on the contamination and radiation issues, which are the most common causes for optical damages and laser failures in space. At first, we will present results based on the study of liquids and subsequently correlate these results to the particulates of the laser system environment. We present a model explaining how the laser beam traps contaminants against the optical surfaces and cause optical damages and the role of gravity in the process. We also report the results of the second harmonic generation efficiency for nonlinear optical crystals irradiated with high-energy beams of protons. In addition, we are proposing to employ the technique of adsorption to minimize the presence of adsorbing molecules present in the laser compartment.

  8. Growth, spectral and optical characterization of a novel nonlinear optical organic material: D-Alanine DL-Mandelic acid single crystal

    Science.gov (United States)

    Jayaprakash, P.; Mohamed, M. Peer; Caroline, M. Lydia

    2017-04-01

    An organic nonlinear optical single crystal, D-alanine DL-mandelic acid was synthesized and successfully grown by slow evaporation solution growth technique at ambient temperature using solvent of aqueous solution. The unit cell parameters were assessed from single crystal X-ray diffraction analysis. The presence of diverse functional groups and vibrational modes were identified using Fourier Transform Infra Red and Fourier Transform Raman spectral analyses. The chemical structure of grown crystal has been identified by Nuclear Magnetic Resonance spectroscopic study. Ultraviolet-visible spectral analysis reveal that the crystal has lower cut-off wavelength down to 259 nm, is a key factor to exhibit second harmonic generation signal. The electronic optical band gap and Urbach energy is calculated as 5.31 eV and 0.2425 eV respectively from the UV absorption profile. The diverse optical properties such as, extinction coefficient, reflectance, linear refractive index, optical conductivity was calculated using UV-visible data. The relative second harmonic efficiency of the compound is found to be 0.81 times greater than that of KH2PO4 (KDP). The thermal stability of the grown crystal was studied by thermogravimetric analysis and differential thermal analysis techniques. The luminescence spectrum exhibited two peaks (520 nm, 564 nm) due to the donation of protons from carboxylic acid to amino group. The Vickers microhardness test was carried out employing one of the as-grown hard crystal and there by hardness number (Hv), Meyer's index (n), yield strength (σy), elastic stiffness constant (C11) and Knoop hardness number (HK) were assessed. The dielectric behaviour of the as-grown crystal was analyzed for different temperatures (313 K, 333 K, 353 K, and 373 K) at different frequencies.

  9. Synthesis, crystal structures, and third-order nonlinear optical properties of a series of ferrocenyl organometallics.

    Science.gov (United States)

    Li, Gang; Song, Yinglin; Hou, Hongwei; Li, Linke; Fan, Yaoting; Zhu, Yu; Meng, Xiangru; Mi, Liwei

    2003-02-10

    Three novel ferrocenyl complexes [Zn(4-PFA)(2)(NO(3))(2)](H(2)O) (1), [Hg(2)(OAc)(4)(4-BPFA)(2)](CH(3)OH) (2), and [Cd(2)(OAc)(4)(4-BPFA)(2)] (3) (4-PFA = [(4-pyridylamino)carbonyl]ferrocene, 4-BPFA = 1,1'-bis[(4-pyridylamino)carbonyl]ferrocene) were prepared, and complexes 1 and 2 were structurally characterized by means of X-ray single-crystal diffraction. In complex 1, the zinc(II) atom is coordinated at a distorted tetrahedral environment by two nitrogen atoms from two 4-PFA moieties and two oxygen atoms from two nitrate anions; [Zn(4-PFA)(2)(NO(3))(2)] units are linked by hydrogen bonds N-H.O and O-H.O forming one-dimensional chains. Complex 2 is a tetranuclear macrocycle compound consisting of two 4-BPFA moieties and two Hg atoms; [Hg(2)(OAc)(4)(4-BPFA)(2)] units form 1-D chains by hydrogen bonds N-H.O as complex 1. Some complexes with 1,1'-bisubstituted pyridine-containing ferrocene ligands have been described, but their crystal data are limited. Compound 2 is the first example of a macrocyclic pyridine-containing ferrocenyl complex. The third-order nonlinear optical (NLO) properties of 4-PFA, 4-BPFA, and complexes 1-3 were determined by Z-scan techniques. The results indicate that all the compounds exhibit strong self-focusing effect. The hyperpolarizability gamma values are calculated to be in the range 1.51 x 10(-)(28) to 3.12 x 10(-)(28) esu. The gamma values are nearly twice as large for complexes 1-3 as for their individual ligands, showing that the optical nonlinearity of the complexes is dominated by the ligands.

  10. Bulk growth, structure, optical properties and laser damage threshold of organic nonlinear optical crystals of Imidazolium L-Ascorbate

    Science.gov (United States)

    Saripalli, Ravi Kiran; Bhat, H. L.; Elizabeth, Suja

    2016-09-01

    Bulk, transparent organic nonlinear optical (NLO) single-crystals of imidazolium L-Ascorbate (ImLA) were grown using slow-evaporation. Crystal structure was determined by single crystal X-ray diffraction analysis. Preliminary linear optical measurements through UV-Visible and infrared spectroscopy revealed good optical transmittance and a low near-UV cutoff wavelength at 256 nm. Kurtz and Perry powder test revealed that ImLA is a phase-matchable NLO material with a second harmonic generation (SHG) efficiency of 1.2 times larger than that of standard KH2PO4 (KDP). Laser damage thresholds were determined for ImLA.

  11. Growth, mechanical, dielectric, thermal and optical studies of a nonlinear optical crystal: L-Histidinium dipicrate dihydrate

    Energy Technology Data Exchange (ETDEWEB)

    Helen, F.; Kanchana, G., E-mail: kanchanagac@gmail.com

    2015-02-01

    Nonlinear optical single crystals of L-histidinium dipicrate dihydrate (LHDPDH) were grown by slow evaporation solution growth technique at room temperature. The microstructure and growth features were analysed by chemical etching. The grown crystal was subjected to X-ray diffraction analysis to confirm its purity and crystal structure. Mechanical behaviour of the grown crystal was analysed by Vicker's microhardness test. The stiffness constant was evaluated for various loads. The dielectric behaviour was investigated at different frequencies and temperatures. AC conductivity and activation energy were determined. Electronic properties, such as valence electron plasma energy, average energy gap or Penn gap, Fermi energy and electronic polarizability were calculated. Thermal analysis confirmed the association of two water molecules in the crystal lattice of LHDPDH and revealed the thermal stability of the crystal. Photoconductivity study reveals that LHDPDH exhibits positive photoconductivity. The optical transmission window and optical band gap of the crystal were found by UV–vis–NIR studies. Second harmonic generation efficiency was found to be 2.5 times that of the standard KDP crystal. The laser damage threshold for the grown crystal was measured using Nd:YAG laser. - Highlights: • High stiffness constant indicates strong binding forces between ions. • Low dielectric constant and dielectric loss at high frequencies. • LHDPDH crystal shows positive photoconductivity. • The laser damage threshold is found to be higher than urea. • SHG efficiency is 2.5 times that of KDP.

  12. Fabrication of optical element from unidirectional grown imidazole-imidazolium picrate monohydrate (IIP) organic crystals for nonlinear optical applications

    Science.gov (United States)

    Vivek, P.; Murugakoothan, P.

    2014-12-01

    Nonlinear optical bulk single crystal of Imidazole-imidazolium picrate monohydrate (IIP) has been grown by Sankaranarayanan-Ramasamy (SR) method using acetonitrile as solvent. First time we report the bulk growth of IIP crystal by SR method. The transparent IIP single crystal of maximum diameter 21 mm and length 46 mm was obtained by employing SR method. The grown crystal was subjected to high resolution X-ray diffraction, UV-vis-NIR transmittance, refractive index, hardness, dielectric and laser damage threshold studies. The crystalline perfection of the grown crystal was analyzed using HRXRD. Cut off wavelength and optical transmission window of the crystal was assessed by UV-vis-NIR and the refractive index of the crystal was found. The mechanical property of the crystal was estimated by Vicker's hardness test. The dielectric property of the crystal was measured as a function of frequency. The laser damage threshold value was determined. The particle size dependent second harmonic generation efficiency for IIP was evaluated with standard reference material potassium dihydrogen phosphate (KDP) by Kurtz-Perry powder method using Nd:YAG laser, which established the existence of phase matching. The second harmonic generation (SHG) of IIP crystal was investigated by the SHG Maker fringes technique. The mechanism of growth is revealed by carrying out chemical etching using acetonitrile as etchant.

  13. On the formation of shocks of electromagnetic plane waves in non-linear crystals

    CERN Document Server

    Christodoulou, Demetrios

    2015-01-01

    An influential result of F. John states that no genuinely non-linear strictly hyperbolic quasi-linear first order system of partial differential equations in two variables has a global $C^2$-solution for small enough initial data. Inspired by recent work of D. Christodoulou, we revisit John's original proof and extract a more precise description of the behaviour of solutions at the time of shock. We show that John's singular first order quantity, when expressed in characteristic coordinates, remains bounded until the final time, which is then characterised by an inverse density of characteristics tending to zero in one point. Moreover, we study the derivatives of second order, showing again their boundedness when expressed in appropriate coordinates. We also recover John's upper bound for the time of shock formation and complement it with a lower bound. Finally, we apply these results to electromagnetic plane waves in a crystal with no magnetic properties and cubic electric non-linearity in the energy density...

  14. On the formation of shocks of electromagnetic plane waves in non-linear crystals

    Science.gov (United States)

    Christodoulou, Demetrios; Perez, Daniel Raoul

    2016-08-01

    An influential result of F. John states that no genuinely non-linear strictly hyperbolic quasi-linear first order system of partial differential equations in two variables has a global C2-solution for small enough initial data. Inspired by recent work of D. Christodoulou, we revisit John's original proof and extract a more precise description of the behaviour of solutions at the time of shock. We show that John's singular first order quantity, when expressed in characteristic coordinates, remains bounded until the final time, which is then characterised by an inverse density of characteristics tending to zero in one point. Moreover, we study the derivatives of second order, showing again their boundedness when expressed in appropriate coordinates. We also recover John's upper bound for the time of shock formation and complement it with a lower bound. Finally, we apply these results to electromagnetic plane waves in a crystal with no magnetic properties and cubic electric non-linearity in the energy density, assuming no dispersion.

  15. Preparation of AgCl Nano-Crystal Embedded Tellurite Nonlinear Optical Glasses under Electric Field Accompanied Heat Treatment

    Institute of Scientific and Technical Information of China (English)

    Jian LIN; Wenhai HUANG; Bofang LI; Chong JIN; Changcheng LIU; Shuhua LEI; Zhenrong SUN

    2008-01-01

    The quantum effect of nano-crystals is an important factor to improve nonlinear optical performance of nano-crystal embedded glasses,while controlling the size distribution and content of nano-crystals in the glass accurately is a key to obtain good quality.The auxiliary direct current electric field,accompanied with heat treatment,was applied on AgCl containing niobic tellurite glass sheet.The nucleation and crystallization of the glass were well controlled under auxiliary electric field.It was found that the average size of AgCl nano-crystal particles in the glass is smaller than that under single heat treatment,and the content of nano-crystals is higher.Therefore the third-order nonlinear optical performance of the glass was increased a lot.The local-area distributed AgCl nano-crystal particles can also be embedded into a glass sheet by using locally applied electric field.

  16. Studies of Second Order Optical Nonlinearities of 4-Aminobenzophenone (ABP) Single Crystal Films

    Science.gov (United States)

    Bhowmik, Achintya; Thakur, Mrinal

    1998-03-01

    Specific organic materials exhibit very high second order optical susceptibilities. Growth of single crystal films of these materials and characterization of nonlinear optical properties are necessary for implementation of device applications. We have grown large-area films ( 1 cm^2 area, 4 μm thick) of ABP by a modification of the shear method. Single crystal nature of the films was confirmed by polarized optical microscopy. X-ray diffraction analysis showed a [100] surface orientation. The absorption spectra revealed transparency from 390 nm to 1940 nm. Significant elements of the second order optical susceptibility tensor were measured by detailed SHG experiments using a Nd:YAG laser (1064 nm, 100 ps, 82 MHz). Second-harmonic power was measured using lock-in detection with carefully selected polarization conditions while the film was rotated about the propagation direction. Using LiNbØas the reference, d-coefficients of ABP were found to be d_23=7.2 pm/V and d_22=0.7 pm/V. Type-I and type-II phase-matching directions were identified on the film by analyzing the optical indicatrix surfaces at fundamental and second-harmonic frequencies.

  17. Synthesis and crystal structure and nonlinear optical properties of polymeric W (Mo)-Cu-S cluster

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jian-liang; CHEN Qi-yuan; GU Ying-ying; ZHONG Shi-an

    2006-01-01

    The polymeric chalcogenide [W2O2S6Cu4(NCMe)4]n (compound 1) was synthesized by the self-assembly reaction of (NH4)2(WOS3) with CuBr in MeCN in the presence of tricyclohexylphosphane (PCy3) under a purified nitrogen atmosphere using standard Schlenk techniques. It gives rise to a novel 1D polymeric compound 1 with solvent MeCN coordinated to the copper atom. This situation is unprecedented in the W(Mo)/Cu/S system. The crystals were characterized by elemental analysis,IR and single-crystal X-ray crystallography. The configuration of the polymeric compound can be viewed as a helical chain which is propagated along the crystallographic c axis. The excited state absorption and refraction of compound 1 in CH3CN solution were studied by using the Z-scan technique with laser pulses of 40 ps pulse-width at a wavelength of 532 nm. The polymeric compound possesses an optical self-focusing performance. The positive nonlinear refraction is attributed to population transitions between singlet states. Compound 1 displays a strong excited-state absorption.

  18. 149.8 nm, the shortest wavelength generated by phase matching in nonlinear crystals

    Science.gov (United States)

    Nakazato, Tomoharu; Ito, Isao; Kobayashi, Yohei; Wang, Xiaoyang; Chen, Chuangtian; Watanabe, Shuntaro

    2017-02-01

    Narrow band light sources in the vacuum ultraviolet (VUV) region are attractive for photo lithography and high resolution photoelectron spectroscopy. Phase matching is essential to generate high power VUV lights by using a narrow band, low peak intensity and nanosecond pump source. In this research, sum frequency mixing has been demonstrated below 150 nm in KBe2BO3F2 by using the fundamental with its fourth harmonic of a 6 kHz Ti:sapphire laser. The laser system we have developed in this research, consists of a Ti:sapphire laser system and a frequency conversion stage. We generated 149.8-nm radiation, which is the shortest wavelength ever obtained to our knowledge by phase matching in nonlinear crystals. The fifth harmonic output powers were 3.6 μW at 149.8 nm and 110 μW at 154.0 nm, respectively. The phase matching angles measured from 149.8 nm to 158.1 nm are larger by 3-4 degrees than those expected from the existing Sellmeier equation. The optical transmission spectra of some KBBF crystals were measured by the spectrophotometer. The transmittance near the absorption edge supports the generation of coherent radiation below 150 nm. The improvement of a prism-coupled device contributed to the generation of coherent radiation below 150 nm. Another reason for the present break through to the shorter wavelength is the use of the short pulse driving source compared with our previous research.

  19. Crystal growth and characterisation of mixed niobates for non-linear optical applications

    CERN Document Server

    Jiang, Q

    1999-01-01

    Temperature tuned NCPM has been realised by using both wavelengths. The measured phase matching temperatures increase with increasing spontaneous polarisation. KLN also has large non-linear optical coefficient (d sub 3 sub 1 =2.14 d sub 3 sub 1 sup l sup i sup N sup b sup O sup 3), a reasonably high damage threshold (1.75 times that of LiNbO sub 3), wide temperature acceptance (approx 5 deg C) and angular acceptance (approx 8 deg). Potassium sodium niobate (K sub x Na sub 1 sub - sub x NbO sub 3 , KNN) crystals have been grown and they are confirmed to be ferroelectric. However, they are unstable and break up into small pieces after a short period of time. By employing ferroelectric phenomenological theory, it is revealed that the birefringence of a ferroelectric crystal consists of two parts: one relating to a ferroelectric free of any electrical displacement and the other depending on the spontaneous polarisation. The theoretical outcomes provide a brief explanation of the experimental results in modifying ...

  20. Structural, mechanical and light yield characterisation of heat treated LYSO:Ce single crystals for medical imaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Mengucci, P., E-mail: p.mengucci@univpm.it [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy); André, G. [Laboratoire Léon Brillouin, CEA-CNRS, CE-Saclay, 91191 Gif sur Yvette cedex (France); Auffray, E. [Department PH-CMX CERN, Route de Meyrin, 1211 Geneva 23 (Switzerland); Barucca, G. [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy); Cecchi, C. [Dipartimento di Fisica e Geologia, Università di Perugia, Via A. Pascoli, 06123 Perugia (Italy); Chipaux, R. [CEA DSM/IRFU/SEDI, CE-Saclay, 91191 Gif sur Yvette cedex (France); Cousson, A. [Laboratoire Léon Brillouin, CEA-CNRS, CE-Saclay, 91191 Gif sur Yvette cedex (France); Davì, F. [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy); Di Vara, N. [Department PH-CMX CERN, Route de Meyrin, 1211 Geneva 23 (Switzerland); Rinaldi, D.; Santecchia, E. [Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona (Italy)

    2015-06-11

    Five single crystals of cerium-doped lutetium yttrium oxyorthosilicate (LYSO:Ce) grown by the Czochralski method were submitted to structural characterisation by X-ray (XRD) and neutron (ND) diffraction, scanning (SEM) and transmission (TEM) electron microscopy and energy dispersive microanalysis (EDS). The Ultimate Tensile Strength (UTS), the Young Modulus (YM) and the Light Yield (LY) of the samples were also measured in order to correlate the mechanical and the optical behaviour of the crystals with the characteristics of their microstructure. Two of the samples analysed were also heat treated at 300 °C for 10 h to evidence possible variations induced by the temperature in the optical and mechanical response of the crystals. Results showed that the mean compositional variations evidenced by the structural analyses do not affect the mechanical and optical behaviour of the samples. On the contrary, the thermal treatment could induce the formation of coherent spherical particles (size 10 to 15 nm), not uniformly distributed inside the sample, that strongly reduce the UTS and YM values, but it does not affect the optical response of the crystal. This latter result was attributed to the low value of the heating temperature (300 °C) that is not sufficiently high to induce annealing of the oxygen vacancies traps that are responsible of the deterioration of the scintillation properties of the LYSO:Ce crystals. This study was carried out in the framework of the Crystal Clear Collaboration (CCC)

  1. Triple-wavelength switchable multiwavelength erbium-doped fiber laser based on a highly nonlinear photonic crystal fiber

    Energy Technology Data Exchange (ETDEWEB)

    Han, Young-Geun [Hanyang University, Seoul (Korea, Republic of)

    2010-04-15

    We propose and experimentally investigate a novel scheme for a triple-wavelength switchable multiwavelength erbium-doped fiber laser based on a highly nonlinear photonic crystal fiber incorporating a multiply-phase-shifted fiber Bragg grating. A nonlinear optical loop mirror based on a highly nonlinear photonic crystal fiber is exploited to suppress the homogeneous line broadening of an erbium-doped fiber amplifier and to provide the triple lasing wavelength switchability. A multiply phase-shifted fiber Bragg grating with three channels, depending on the number of phase-shifted segments, is implemented to establish a multichannel filter and to generate the multiwavelength output. A high-quality multiwavelength output with a high extinction ratio of {approx}45 dB and a high output flatness of {approx}0.3 dB is realized. The switching performance to provide lasing-wavelength selectivity can be realized by using a nonlinear polarization rotation based on a nonlinear optical loop mirror. The lasing wavelength can be switched individually by controlling both the polarization controller within the nonlinear optical loop mirror and the cavity loss. The proposed multiwavelength fiber laser can be operated in the single-, dual-, and triple-lasing wavelength states. Based on the bending technique, the lasing wavelength of the proposed multiwavelength erbium-doped fiber laser can be readily controlled, and its tunability was measured to be {approx}7.2 nm/m{sup -1}.

  2. Structural, mechanical and light yield characterisation of heat treated LYSO:Ce single crystals for medical imaging applications

    CERN Document Server

    Mengucci, P; Auffray, E; Barucca, G; Cecchi, C; Chipaux, R; Cousson, A; Davì, F; Di Vara, N; Rinaldi, D; Santecchia, E

    2015-01-01

    Five single crystals of cerium-doped lutetium yttrium oxyorthosilicate (LYSO:Ce) grown by the Czochralski method were submitted to structural characterisation by X-ray (XRD) and neutron (ND) diffraction, scanning (SEM) and transmission (TEM) electron microscopy and energy dispersive microanalysis (EDS). The Ultimate Tensile Strength (UTS), the Young Modulus (YM) and the Light Yield (LY) of the samples were also measured in order to correlate the mechanical and the optical behaviour of the crystals with the characteristics of their microstructure. Two of the samples analysed were also heat treated at 300 °C for 10 h to evidence possible variations induced by the temperature in the optical and mechanical response of the crystals. Results showed that the mean compositional variations evidenced by the structural analyses do not affect the mechanical and optical behaviour of the samples. On the contrary, the thermal treatment could induce the formation of coherent spherical particles (size 10 to 15 nm), not unifo...

  3. Variational principles for linear and nonlinear mixtures: New derivations and application to bilinear materials and yield behavior

    Science.gov (United States)

    Alqaraleh, Sahar Mubarak

    2006-04-01

    We study in this paper the effective energy potential of nonlinear composites in terms of the corresponding energy potential for linear material. We study this for power law material using Suquet's variational principle, for bilinear material using Ponte Castaneda variational principle, and we studied the yield behavior as limiting cases of both. We show that three established variational principles can be derived from the Cauchy-Buniakowski-Schwartz inequality; these variational principles (bounds) are: (a) bounds on yield behavior of mixtures, (b) The Hashin-Shtrikman variational principle for linear materials, (c) The Debotton and Ponte Castaneda bound for power-law polycrystals. We also compute the actual stress and strain fields for laminate material for two choices of the average strain, and compute a bound on the effective potential for spherical inclusions using Hashin's linear bound, as well as for spheroidal inclusions using Willis's linear bound. We obtained bounds sharper than the established bounds for both laminate and aligned ellipsoids geometry, and we investigate also how the bound depends on the specified geometry and on specific parameters of the problem.

  4. Creation technique and nonlinear optics of dynamic one-dimensional photonic crystals in colloidal solution of quantum dots

    Science.gov (United States)

    Smirnov, A. M.; Golinskaya, A. D.; Ezhova, K.; Kozlova, M.; Stebakova, J. V.; Valchuk, Y. V.

    2017-05-01

    One-dimensional dynamic photonic crystal was formed by a periodic spatial modulation of dielectric permittivity induced by the two ultrashort laser pulses interference in semiconductor quantum dots CdSe/ZnS (QDs) colloidal solution intersecting at angle θ. The fundamental differences of dynamic photonic crystals from static ones which determine the properties of these transient structures are the following. I. Dynamic photonic crystals lifetimes are determined by the nature of nonlinear changes of dielectric permittivity. II. The refractive index changing is determined by the intensity of the induced standing wave maxima and nonlinear susceptibility of the sample. We use the pump and probe method to create the dynamic one-dimensional photonic crystal and to analyze its features. Two focused laser beams are the pump beams, that form in the colloidal solution of quantum dots dynamic one-dimensional photonic crystal. The picosecond continuum, generated by the first harmonic of laser (1064 nm) passing through a heavy water is used as the probe beam. The self-diffraction of pumping beams on self induced dynamic one-dimensional photonic crystal provides information about spatial combining of laser beams.

  5. Crystal growth, perfection, linear and nonlinear optical, photoconductivity, dielectric, thermal and laser damage threshold properties of 4-methylimidazolium picrate: an interesting organic crystal for photonic and optoelectronic devices

    Science.gov (United States)

    Rajesh, K.; Arun, A.; Mani, A.; Praveen Kumar, P.

    2016-10-01

    The 4-methylimidazolium picrate has been synthesized and characterized successfully. Single and powder x-ray diffraction studies were conducted which confirmed the crystal structure, and the value of the strain was calculated. The crystal perfection was determined by a HRXR diffractometer. The transmission spectrum exhibited a better transmittance of the crystal in the entire visible region with a lower cut-off wavelength of 209 nm. The linear absorption value was calculated by the optical limiting method. A birefringence study was also carried out. Second and third order nonlinear optical properties of the crystal were found by second harmonic generation and the z-scan technique. The crystals were also characterized by dielectric measurement and a photoconductivity analyzer to determine the dielectric property and the optical conductivity of the crystal. The laser damage threshold activity of the grown crystal was studied by a Q-switched Nd:YAG laser beam. Thermal studies established that the compound did not undergo a phase transition and was stable up to 240 °C.

  6. Impact of dyes on the nonlinear optical response of liquid crystals implementing the Z-scan technique

    Science.gov (United States)

    Rodríguez-Rosales, A. A.; Ortega-Martínez, R.; Morales-Saavedra, O. G.

    2011-01-01

    The study of the nonlinear refractive index response γ of several organic dyes and their impact on the nonlinear optical (NLO) properties of nematic liquid crystals (LC) was performed via Z-scan measurements. For his purpose, a low power CW He-Ne laser system (λ approx 633 nm) was implemented. Studies were carried out at the low absorption spectroscopic region of the implemented samples (dyes, liquid crystals and mixtures at different ratios of these materials). Samples were prepared at 1% weight of the used solvent (THF) and were sandwiched in glass cells with a gap thickness of ~100 μm. The implemented dyes have shown the largest optical nonlinearities and represent the main contributors to the cubic NLO-properties of the LC:Dye mixtures. In our particular studies, 5CB liquid crystal doped with DR1 azo-dye, resulted in the simultaneous positive and negative exhibition of nonlinear refractive indexes γ, depending on the polarization state of the excitation laser beam. Experimental conditions and results are described in detail.

  7. Bulk crystal growth, optical, mechanical and ferroelectric properties of new semiorganic nonlinear optical and piezoelectric Lithium nitrate monohydrate oxalate single crystal

    Science.gov (United States)

    Dalal, Jyoti; Kumar, Binay

    2016-01-01

    New semiorganic nonlinear optical single crystals of Lithium nitrate oxalate monohydrate (LNO) were grown by slow evaporation solution technique. Single crystal X-ray diffraction study indicated that LNO crystal belongs to the triclinic system with space group P1. Various functional groups present in the material were identified by FTIR and Raman analysis. UV-vis study showed the high transparency of crystals with a wide band gap 5.01 eV. Various Optical constants i.e. Urbach energy (Eu), extinction coefficient (K), refractive index, optical conductivity, electric susceptibility with real and imaginary parts of dielectric constant were calculated using the transmittance data which have applications in optoelectronic devices. A sharp emission peak was found at 438 nm in photoluminescence measurement, which revealed suitability of crystal for fabricating violet lasers. In dielectric studies, a peak has been observed at 33 °C which is due to ferroelectric to paraelectric phase transition. Piezoelectric charge coefficients (d33 = 9.2 pC/N and g33) have been calculated, which make it a suitable for piezoelectric devices applications. In ferroelectric studies, a saturated loop was found in which the values of coercive field and remnant polarization were found to be 2.18 kV/cm and 0.39 μC/cm2, respectively. Thermal behavior was studied by TGA and DSC studies. The relative SHG efficiency of LNO was found to be 1.2 times that of KDP crystal. In microhardness study, Meyer's index value was found to be 1.78 which revealed its soft nature. These optical, dielectric, piezoelectric, ferroelectric, mechanical and non-linear optical properties of grown crystal establish the usefulness of this material for optoelectronics, non-volatile memory and piezoelectric devices applications.

  8. Growth and Characterization of Lithium Potassium Phthalate (LiKP) Single Crystals for Third Order Nonlinear Optical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Sivakumar, B.; Mohan, R. [Preidency College, Bangalore (India); Raj, S. Gokul [RR and Dr. SR Technical Univ., Avadi (India); Kumar, G. Ramesh [Anna Univ., Arni (India)

    2012-11-15

    Single crystals of lithium potassium phthalate (LiKP) were successfully grown from aqueous solution by solvent evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction. The lithium potassium phthalate C{sub 16} H{sub 12} K Li{sub 3} O{sub 11} belongs to triclinic system with the following unit-cell dimensions at 298(2) K; a = 7.405(5) A; b = 9.878(5) A; c = 13.396(5) A; α = 71.778(5) .deg.; β = 87.300(5) .deg.; γ = 85.405(5) .deg.; having a space group P1. Mass spectrometric analysis provides the molecular weight of the compound and possible ways of fragmentations occurs in the compound. Thermal stability of the crystal was also studied by both simultaneous TGA/DTA analyses. The UV-Vis-NIR spectrum shows a good transparency in the whole of Visible and as well as in the near IR range. Third order nonlinear optical studies have also been studied by Z-scan technique. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated.

  9. Growth and characterization studies of sodium Di(L-Malato) borate bulk single crystal: A promising nonlinear optical material

    Science.gov (United States)

    Senthil, A.; Loganayaki, M.; Lenin, M.; Ramasamy, P.

    2012-06-01

    A semi-organic nonlinear optical material, sodium di(L-malato) borate (NaDMB) has been synthesized. Optically good quality bulk single crystal of NaDMB was successfully grown by slow evaporation solution technique (SEST) and Sankaranarayanan-Ramasamy (SR) method at 36 °C. Transparent, colourless crystal of size 22 mm X 8 mm X 6 mm with well defined morphology was grown by SEST and oriented unidirectional bulk single crystal of size 48 mm length and 16 mm diameter was grown by SR method. The grown crystals were subjected to single crystal X-ray diffraction studies. The crystal belongs to monoclinic structure with space group P21. The grown crystals were characterized by UV-vis studies. The structural perfection of the grown crystal has been analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. The differential thermal (DTA) and thermogravimetric (TG) analysis traces reveal the thermal stability of the sample. The second-harmonic generation efficiency was estimated by Kurtz and Perry powder technique.

  10. Linear and nonlinear optical characterization of methyl-p-hydroxybenzoate (p-MHB) single crystal grown by TSSG method

    Science.gov (United States)

    Sritharan, K.; Manikandan, V.; Srinivasan, K.

    2017-06-01

    The nonlinear optical single crystal methyl-p-hydroxybenzoate (p-MHB) was grown by employing top seeded solution growth method (TSSG) for the first time. A good quality small size crystal grown from methanol solution was inserted into the melt as a seed for growth after seasoning it around the melt temperature. Highly transparent optical quality p-MHB single crystal with regular faceting was harvested after the successful growth run. The unit cell parameter of the grown crystal was determined by powder X-ray diffraction (PXRD) and the crystal structure was confirmed by single crystal X-ray diffraction (SCXRD) methods. The UV-Vis-NIR absorption spectrum has been recorded in the range 200-2700 nm and it shows that the lower cutoff wavelength exits at 307 nm. The study indicates that the grown crystal has good optical transparency window in the visible and near IR region in the range 307-2136 nm. Second harmonic generation (SHG) efficiency of the grown crystal was studied by Kurtz-Perry powder method with 1064 nm Nd: YAG laser beam as a fundamental source and it was about twice that the standard KDP.

  11. Z-scan measurement of the nonlinear refractive index of Nd(3+), Y(3+)-codoped CaF(2) and SrF(2) crystals.

    Science.gov (United States)

    Guo, Yue; Lu, Shunbin; Su, Liangbi; Zhao, Chujun; Zhang, Han; Wen, Shuangchun

    2015-02-01

    By performing the Z-scan measurements at 800 nm using a femtosecond pulsed laser, we are able to characterize the nonlinear refractive indices of Nd, Y codoped CaF(2) and SrF(2) crystals. Based on our measured results, we conclude that the doped fluoride crystal possesses a small nonlinear refractive index and the doping of Nd(3+) and Y(3+) ions in CaF(2) can change its third-order nonlinear index, but the contribution is minor. The doped fluoride crystal may have large potential to be developed as the next generation of gain material for a high-energy laser system.

  12. Studies on the growth, structural, spectral and third-order nonlinear optical properties of Ammonium 3-carboxy-4-hydroxy benzenesulfonate monohydrate single crystal

    Science.gov (United States)

    Silambarasan, A.; Krishna Kumar, M.; Thirunavukkarasu, A.; Mohan Kumar, R.; Umarani, P. R.

    2015-01-01

    An organic nonlinear optical bulk single crystal, Ammonium 3-carboxy-4-hydroxy benzenesulfonate monohydrate (ACHBS) was successfully grown by solution growth technique. Single crystal X-ray diffraction study confirms that, the grown crystal belongs to P21/c space group. Powder X-ray diffraction and high resolution X-ray diffraction analyses revealed the crystallinity of the grown crystal. Infrared spectral analysis showed the vibrational behavior of chemical bonds and its functional groups. The thermal stability and decomposition stages of the grown crystal were studied by TG-DTA analysis. UV-Visible transmittance studies showed the transparency region and cut-off wavelength of the grown crystal. The third-order nonlinear optical susceptibility of the grown crystal was estimated by Z-scan technique using Hesbnd Ne laser source. The mechanical property of the grown crystal was studied by using Vicker's microhardness test.

  13. Plastic yielding and work hardening of single crystals in a soft device

    Science.gov (United States)

    Le, K. C.; Nguyen, Q. S.

    2009-11-01

    An analytical solution to the problem of an anti-plane constrained shear of single crystals placed in a soft device within the continuum dislocation theory is found. The dependence of the nucleation stress on the grain size exhibits a modest deviation from the Hall-Petch relation. It is shown that, as soon as the dissipation is taken into account, the hardening behavior becomes nearly identical to that of single crystals in a hard device. To cite this article: K.C. Le, Q.S. Nguyen, C. R. Mecanique 337 (2009).

  14. Invited Article: Multiple-octave spanning high-energy mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    Science.gov (United States)

    Zhou, Binbin; Bache, Morten

    2016-08-01

    Bright and broadband coherent mid-IR radiation is important for exciting and probing molecular vibrations. Using cascaded nonlinearities in conventional quadratic nonlinear crystals like lithium niobate, self-defocusing near-IR solitons have been demonstrated that led to very broadband supercontinuum generation in the visible, near-IR, and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal is pumped in the mid-IR. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed. The results were recorded in a commercially available crystal LiInS2 pumped in the 3-4 μm range with 85 fs 50 μJ pulse energy, with the broadest supercontinuum covering 1.6-7.0 μm. We measured up 30 μJ energy in the supercontinuum, and the energy promises to scale favorably with an increased pump energy. Other mid-IR crystals can readily be used as well to cover other pump wavelengths and target other supercontinuum wavelength ranges.

  15. Effect of dislocation pile-up on size-dependent yield strength in finite single-crystal micro-samples

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Bo; Shibutani, Yoji, E-mail: sibutani@mech.eng.osaka-u.ac.jp [Department of Mechanical Engineering, Osaka University, Suita 565-0871 (Japan); Zhang, Xu [State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi' an Jiaotong University, Xi' an 710049 (China); School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou 450001 (China); Shang, Fulin [State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi' an Jiaotong University, Xi' an 710049 (China)

    2015-07-07

    Recent research has explained that the steeply increasing yield strength in metals depends on decreasing sample size. In this work, we derive a statistical physical model of the yield strength of finite single-crystal micro-pillars that depends on single-ended dislocation pile-up inside the micro-pillars. We show that this size effect can be explained almost completely by considering the stochastic lengths of the dislocation source and the dislocation pile-up length in the single-crystal micro-pillars. The Hall–Petch-type relation holds even in a microscale single-crystal, which is characterized by its dislocation source lengths. Our quantitative conclusions suggest that the number of dislocation sources and pile-ups are significant factors for the size effect. They also indicate that starvation of dislocation sources is another reason for the size effect. Moreover, we investigated the explicit relationship between the stacking fault energy and the dislocation “pile-up” effect inside the sample: materials with low stacking fault energy exhibit an obvious dislocation pile-up effect. Our proposed physical model predicts a sample strength that agrees well with experimental data, and our model can give a more precise prediction than the current single arm source model, especially for materials with low stacking fault energy.

  16. Fabrication of air-bridged Kerr nonlinear polymer photonic crystal slab structures in near-infrared region

    Institute of Scientific and Technical Information of China (English)

    Ziming Meng; Xiaolan Zhong; Chen Wang; Zhiyuan Li

    2012-01-01

    Fabrication details of air-bridged Kerr nonlinear polymer photonic crystal slab structures are presented.Both the two-dimensional photonic crystal slab and the one-dimensional nanobeam structures are fabricated using direct focused ion beam etching and subsequent wet chemical etching.The scanning electron microscopy images show the uniformity and homogeneity of the cylindrical air holes.The optical measurement in the near-infrared region is implemented using the tapered fiber coupling method,and the results agree with the numerical calculations by using the three-dimensional finite-difference time-domain method.

  17. Synthesis, Crystal Growth and Characterization of bis Dl-Valine Picrate Single Crystal for Second-Order Nonlinear Optical Applications

    Science.gov (United States)

    Silambarasan, A.; Krishna Kumar, M.; Sudhahar, S.; Thirunavukkarasu, A.; Mohan Kumar, R.; Umarani, P. R.

    2013-08-01

    An organic compound Bis DL-Valine picrate (BDLVP) was synthesized successfully and single crystal was grown by slow evaporation solution growth method. The presence of functional groups in the compound was identified by FTIR spectral analysis. Single crystal X-ray diffraction study revealed that the grown crystal belongs to P21/n space group of monoclinic crystal system. Powder X-ray diffraction pattern was recorded to know the crystalline perfection of the grown crystal. The reaction mechanism, thermal decomposition stages and thermal stability of the grown crystal were studied by using TG/DTA analysis. From the UV-visible spectral study, the electronic band gap energy (Eg) of the grown crystal was found to be 2.43 eV. The second harmonic generation (SHG) efficiency of grown crystal was found to be 1.3 times higher than KDP crystal by using Kurtz powder SHG technique. The microhardness property of the grown crystal was examined by Vicker's microhardness test.

  18. All optical NAND gate based on nonlinear photonic crystal ring resonator

    Directory of Open Access Journals (Sweden)

    Somaye Serajmohammadi

    2016-06-01

    Full Text Available In this paper we proposed a new design for all optical NAND gate. By combining nonlinear Kerr effect with photonic crystal ring resonators, we designed an all optical NAND gate. A typical NAND gate is a logic device with one bias and two logic input and one output ports. It has four different combinations for its logic input ports. The output port of the NAND gate is OFF, when both logic ports are ON, otherwise the output port will be ON. The switching power threshold obtained for this structure equals to 1.5 kW/μm2. For designing the proposed optical logic gate we employed one resonant ring whose resonant wavelength is at 1554 nm. The functionality of the proposed NAND gate depends on the operation of this resonant ring. When the power intensity of optical waves is less than the switching threshold the ring will couple optical waves into drop waveguide otherwise the optical waves will propagate on the bus waveguide.

  19. Directional asymmetry of the nonlinear wave phenomena in a three-dimensional granular phononic crystal under gravity.

    Science.gov (United States)

    Merkel, A; Tournat, V; Gusev, V

    2014-08-01

    We report the experimental observation of the gravity-induced asymmetry for the nonlinear transformation of acoustic waves in a noncohesive granular phononic crystal. Because of the gravity, the contact precompression increases with depth inducing space variations of not only the linear and nonlinear elastic moduli but also of the acoustic wave dissipation. We show experimentally and explain theoretically that, in contrast to symmetric propagation of linear waves, the amplitude of the nonlinearly self-demodulated wave depends on whether the propagation of the waves is in the direction of the gravity or in the opposite direction. Among the observed nonlinear processes, we report frequency mixing of the two transverse-rotational modes belonging to the optical band of vibrations and propagating with negative phase velocities, which results in the excitation of a longitudinal wave belonging to the acoustic band of vibrations and propagating with positive phase velocity. We show that the measurements of the gravity-induced asymmetry in the nonlinear acoustic phenomena can be used to compare the in-depth distributions of the contact nonlinearity and of acoustic absorption.

  20. Study of Welding Distortion and Residual Stress Considering Nonlinear Yield Stress Curves and Multi-constraint Equations

    Science.gov (United States)

    Rong, Youmin; Zhang, Guojun; Huang, Yu

    2016-10-01

    Inherent strain analysis has been successfully applied to predict welding deformations of large-scale structural components, while thermal-elastic-plastic finite element method is rarely used for its disadvantages of long calculation period and large storage space. In this paper, a hybrid model considering nonlinear yield stress curves and multi-constraint equations to thermal-elastic-plastic analysis is further proposed to predict welding distortions and residual stresses of large-scale structures. For welding T-joint structural steel S355JR by metal active gas welding, the published experiment results of temperature and displacement fields are applied to illustrate the credibility of the proposed integration model. By comparing numerical results of four different cases with the experiment results, it is verified that prediction precision of welding deformations and residual stresses is apparently improved considering the power-law hardening model, and computational time is also obviously shortened about 30.14% using multi-constraint equations. On the whole, the proposed hybrid method can be further used to precisely and efficiently predict welding deformations and residual stresses of large-scale structures.

  1. Extinction ratio improvement by pump-modulated four-wave mixing in a dispersion-flattened nonlinear photonic crystal fiber.

    Science.gov (United States)

    Chow, K K; Shu, C; Lin, Chinlon; Bjarklev, A

    2005-10-31

    We demonstrate extinction ratio improvement by using pump-modulated four-wave mixing in a dispersion-flattened nonlinear photonic crystal fiber. A 6-dB improvement in the extinction ratio of a degraded return-to-zero signal has been achieved. A power penalty improvement of 3 dB at 10(-9) bit-error-rate level is obtained in the 10 Gb/s bit-error-rate measurements.

  2. Efficient conversion from infrared to red light by cascaded nonlinear optical processes using an aperiodically poled lithium niobate crystal

    Directory of Open Access Journals (Sweden)

    Juan Eduardo González

    2015-12-01

    Full Text Available We present a scheme for conversion of pulsed light from the infrared to the red spectral region, using an aperiodically poled ferroelectric crystal within a resonant cavity in which two cascaded nonlinear optical processes occur when pumped with a pulsed Nd:YAG laser. This device emits 9 ns pulses of over 1 mJ at 710 nm and is a viable source for future biomedical applications.

  3. Influence of formic acid on electrical, linear and nonlinear optical properties of potassium dihydrogen phosphate (KDP) crystals

    Energy Technology Data Exchange (ETDEWEB)

    Anis, Mohd [Crystal Growth Laboratory, Department of Physics, Milliya Arts, Science and Management Science College, Beed 431122, Maharashtra (India); Shirsat, M.D. [Intelligent Material Research Laboratory, Department of Physics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad 431005,Maharashtra (India); Muley, Gajanan [Department of Physics, Sant Gadge Baba Amravati University, Amravati 444602, Maharashtra (India); Hussaini, S.S., E-mail: Shuakionline@yahoo.co.in [Crystal Growth Laboratory, Department of Physics, Milliya Arts, Science and Management Science College, Beed 431122, Maharashtra (India)

    2014-09-15

    In present investigation 0.5 and 1 mol% formic acid (FA) added potassium dihydrogen phosphate (KDP) crystals have been grown by a slow evaporation technique. The cell parameters of the grown crystals were determined using single crystal X-ray diffraction analysis. The presence of different functional groups has been qualitatively analyzed by the FT-IR spectral analysis. The optical transparency and optical constants were assessed employing UV–visible studies in the range of 200–900 nm. The wide optical band gap of 1 mol% FA added KDP has been found to be 5 eV. The frequency dependent dielectric measurements were studied for pure and KDP added FA crystals. The enhanced second harmonic generation (SHG) efficiency of grown crystals was determined by a classical Kurtz–Perry powder technique. The encouraging third order nonlinear properties were examined employing a Z-scan technique using He–Ne laser, at 632.8 nm. The effective negative index of refraction and high figure of merit (FOM) essential for laser stabilization were determined for grown crystals. - Highlights: • Study on electrical and optical properties of formic acid (FA) added KDP was reported for the first time. • Optical properties were found to be enhanced with increasing concentration of FA. • The SHG efficiency of 1 mol% FA added KDP was 1.13 times that of KDP. • The high concentration of FA contributed lower dielectric properties to KDP suitable for microelectronics applications. • The improved third order nonlinear parameters were ascertained with addition of FA in KDP crystal.

  4. Synthesis, crystal growth, structural, spectral, thermal, mechanical, linear and nonlinear optical studies of organic single crystal 4-Iodo 4-nitrostilbene (IONS): A potential NLO material

    Energy Technology Data Exchange (ETDEWEB)

    Dinakaran, Paul M.; Kalainathan, S., E-mail: kalainathan@yahoo.com

    2013-12-16

    An organic nonlinear optical material 4-Iodo 4-nitrostilbene (IONS) has been synthesized and good optical quality single crystal was grown from ethyl methyl ketone solvent by the solution growth technique. Single and powder X-ray diffraction analyses reveals that the grown crystal belongs to monoclinic crystal system with noncentrosymmetric space group ‘P2{sub 1}’ and it has good crystalline nature. Functional groups and molecular structure of the title compound were confirmed by FTIR and {sup 1}H NMR respectively. The UV–Vis–NIR absorption study reveals no absorption in the visible region and the cut-off wavelength was found to be at 412.84 nm, TG/DTA, mass spectral analysis, photoluminescence and microhardness studies have been carried out for the grown crystals and results are discussed in detail. The second harmonic efficiency of the IONS was determined by Kurtz–Perry powder technique which reveals that the IONS crystal (3.1 V) has greater efficiency i.e., 143 times to that of KDP (21.7 mV). - Highlights: • The 4-Iodo 4-nitrostilbene (IONS) material has been synthesized by Wittig reaction. • The single crystal was grown for the first time with dimensions of 9.5 × 4 × 1.5 mm{sup 3}. • SHG efficiency of IONS is 143 times greater than that of KDP crystal. • The UV–Vis absorption study reveals that the transparency was found to be good. • IONS crystal is a potential candidate for optoelectronic applications.

  5. Computational studies of third-order nonlinear optical properties of pyridine derivative 2-aminopyridinium p-toluenesulphonate crystal

    Indian Academy of Sciences (India)

    ANUJ KUMAR; MAHESH PAL SINGH YADAV

    2017-07-01

    We have reported a theoretical investigation on nonlinear optical behaviour, electronic and optical properties and other molecular properties of the organic nonlinear optical crystal 2-aminopyridinium ptoluenesulphonate(APPTS). The computation has been done using density functional theory (DFT) methodemploying 6-31G(d) basis set and Becke’s three-parameter hybrid functional (B3LYP). Calculated values of static hyperpolarizability confirm the good nonlinear behaviour of the molecule. Electronic behaviour and global reactivity descriptor parameters are calculated and analysed using HOMO–LUMO analysis. Energy band gap and simulated UV–visible spectrum show good agreement with experimental results. Other important molecular properties like rotational constant, zero-point vibrational energy, total energy at room temperature and pressure have also beencalculated in the ground state.

  6. Computational studies of third-order nonlinear optical properties of pyridine derivative 2-aminopyridinium p-toluenesulphonate crystal

    Science.gov (United States)

    Kumar, Anuj; Yadav, Mahesh Pal Singh

    2017-07-01

    We have reported a theoretical investigation on nonlinear optical behaviour, electronic and optical properties and other molecular properties of the organic nonlinear optical crystal 2-aminopyridinium p-toluenesulphonate (APPTS). The computation has been done using density functional theory (DFT) method employing 6-31G(d) basis set and Becke's three-parameter hybrid functional (B3LYP). Calculated values of static hyperpolarizability confirm the good nonlinear behaviour of the molecule. Electronic behaviour and global reactivity descriptor parameters are calculated and analysed using HOMO-LUMO analysis. Energy band gap and simulated UV-visible spectrum show good agreement with experimental results. Other important molecular properties like rotational constant, zero-point vibrational energy, total energy at room temperature and pressure have also been calculated in the ground state.

  7. Super Continuum Generation at 1310nm in a Highly Nonlinear Photonic Crystal Fiber with a Minimum Anomalous Group Velocity Dispersion

    Directory of Open Access Journals (Sweden)

    Ashkan Ghanbari

    2014-12-01

    Full Text Available In the present study, we investigate the evolution of the super continuum generation (SCG through the triangular photonic crystal fiber (PCF at 1310nm by using both full-vector multi pole method (M.P.M and novel concrete algorithms: Symmetric Split-step Fourier (SSF and fourth order Runge Kutta(RK4 which is an accurate method to solve the general nonlinear Schrodinger equation (GNLSE. We propose an ideal solid-core PCF structure featuring a minimum anomalous group velocity dispersion (GVD, small higher order dispersions (HODs and enhanced nonlinearity for appropriate super continuum generation with low input pulse energies over discrete distances of the PCF. We also investigate the impact of the linear and nonlinear effects on the super continuum spectra in detail and compare the results with different status.

  8. High stable, high efficient ultraviolet laser with angle-phase-mismatching compensation by adjusting temperature of the nonlinear crystals

    Science.gov (United States)

    Yang, Houwen; Wang, Bo; Wang, Junhua; Li, Xiaofang; Liu, Zhaojun; Cheng, Wenyong

    2017-03-01

    We demonstrated an ultraviolet laser at 355 nm using a type-I and a type-II phase-matching nonlinear optical crystal of LiB3O5 (LBO). A method of adjusting temperature for compensation is presented. The crystal temperature is controlled by proportional integral derivative (PID) thermal controllers with a  ±0.01 °C resolution. The value of wave vector mismatch, distance of light propagation in nonlinear crystals, effective nonlinear coefficient, theoretical analysis and calculation of conversion efficiency versus temperature are discussed. The experimental results show that the average output power of the 355 nm laser is 1.24 W with the pump power of 13.33 W, when the repetition frequency is 15 kHz. The pulse duration is 9.8 ns, and the beam quality factors are of Mx2   =  1.8, My2   =  1.7. The conversion efficiency from 808 nm to 355 nm laser is 9.3%, which nearly reaches the optimum value reported so far and is limited by the wavelength mismatch between the pumping and absorbing lasers. The 355 nm output power instability of the laser device is 0.45% in 2 h. A compact no-water-cooling ultraviolet laser with high stability and high efficiency is obtained.

  9. Improved Slow-Positron Yield using a Single Crystal Tungsten Moderator

    DEFF Research Database (Denmark)

    Vehanen, A.; Lynn, K. G.; Schultz, P. J.

    1983-01-01

    A well-annealed W(110) single crystal was used as a fast-to-slow positron moderator. The measured moderator efficiency at room temperature using a58Co positron source in the backscattering geometry isɛ =(3.2±0.4)×10−3, roughly a factor of three better thanɛ for the best previously reported Cu(111...

  10. Synthesis, growth and characterization of new organic crystal: 2-Aminopyridinium p-Toluenesulfonate for third order nonlinear optical applications

    Science.gov (United States)

    Bincy, I. P.; Gopalakrishnan, R.

    2014-09-01

    2-Aminopyridinium p-Toluenesulfonate (2APPTS), an organic NLO crystal, was grown for the first time by the slow evaporation solution technique. Single crystal X-ray diffraction analysis reveals that 2APPTS belongs to monoclinic crystal system with centrosymmetric space group P21/n. The determined lattice parameters are a=8.580(7) Å, b=6.419(5) Å, c=23.277(18) Å, β=100.016(3)° and volume=1262.58(3) Å3. Powder XRD study reveals the crystalline nature of the grown sample. FT-IR and FT-Raman studies were carried out to identify the functional groups present in 2APPTS. FT-NMR spectral study confirms the number of protons and carbon present in the molecular structure of the title compound. Thermal behavior and stability of 2APPTS were investigated by thermogravimetric (TG) and differential thermal analyses (DTA). Transparency of the title crystal in UV-vis-NIR region was analyzed and the optical band gap energy was found to be 3.6 eV. The mechanical properties of the grown crystals have been analyzed by the Vickers microhardness method. The etching studies reveal the growth pattern and dislocations present in the grown 2APPTS crystal. The negative third order nonlinear optical parameters like refractive index (n2), absorption coefficient (β) and susceptibility (χ(3)) were estimated by Z-scan studies.

  11. Growth and characterization of Bis(L-threonine) copper (II) monohydrate single crystals: A semiorganic second order nonlinear optical material

    Science.gov (United States)

    Subhashini, R.; Sathya, D.; Sivashankar, V.; Latha Mageshwari, P. S.; Arjunan, S.

    2016-12-01

    Highly transparent solitary nonlinear semiorganic optical material Bis(L-threonine) copper (II) monohydrate [BLTCM], was synthesized by a conventional slow evaporation solution growth technique. The grown crystals were subjected to structural, optical, electrical, thermal, mechanical, SHG and Laser damage threshold studies. Single crystal XRD shows that the material crystallizes in monoclinic system with noncentrosymmetric space group P21. FT-IR and FT-RAMAN analyses confirm the various functional groups present in the grown crystal. The transparency range of BLTCM was determined by UV-vis-NIR studies and various optical constants such as extinction coefficient (K), refractive index, optical conductivity and electric susceptibility with real and imaginary parts of dielectric constant were calculated using the transmittance data which have applications in optoelectronic devices. Dielectric studies of the crystal were carried out at different frequencies and temperatures to analyze the electrical properties. TGA and DSC analyses were performed to study the thermal behaviour of the sample. The hardness stability of the grown specimen was investigated by Vickers microhardness test. The output intensity of second harmonic generation was confirmed using the Kurtz and Perry powder method. The laser induced surface damage threshold of the crystal was measured using Nd:YAG laser.

  12. Growth, thermal, dielectric and mechanical properties of L-phenylalanine-benzoic acid: A nonlinear optical single crystal

    Science.gov (United States)

    Tamilselvan, S.; Vimalan, M.; Vetha Potheher, I.; Rajasekar, S.; Jeyasekaran, R.; Antony Arockiaraj, M.; Madhavan, J.

    2013-10-01

    An efficient amino acid family nonlinear optical single crystal L-phenylalanine-benzoic acid (LPB) was conveniently grown by slow evaporation technique at room temperature. The crystal system and the lattice parameters were analyzed by single crystal X-ray diffraction studies. The grown crystal has excellent transmission in the entire visible region and its lower cut-off wavelength was found to be 248 nm. The SHG efficiency of the grown crystal was found to be 1.6 times higher than that of KDP crystal. The Laser damage threshold value of LPB has been found to be 6.5 GW/cm2. The sample was thermally stable up to 134 °C. Microhardness, dielectric and AC/DC conductivity measurements were made along (0 0 1) plane and reported for the first time. Microhardness studies revealed that the sample belongs to hard nature. Frequency dependent dielectric constant was measured for different temperatures and found maximum dielectric constant of 14 for 363 K. Photoconductivity studies of LPB divulged its negative photoconducting nature.

  13. Synthesis, crystal growth and characterization of a phase matchable nonlinear optical single crystal: p-chloro dibenzylideneacetone

    Science.gov (United States)

    Ravindra, H. J.; John Kiran, A.; Nooji, Satheesha Rai; Dharmaprakash, S. M.; Chandrasekharan, K.; Kalluraya, Balakrishna; Rotermund, Fabian

    2008-05-01

    Good quality single crystals of p-chloro dibenzylideneacetone (CDBA) of size 13 mm×8 mm×2 mm were grown by slow evaporation solution growth technique. The grown crystals were confirmed by elemental analysis, Fourier transform infrared (FTIR) analysis and single crystal X-ray diffraction techniques. From the thermo gravimetric/differential thermal (TG/DT) analysis, the CDBA was found to be thermally stable up to 250 °C. The mechanical stability of the crystal is comparable with that of the other reported chalcones. The lower optical cut-off wavelength for this crystal was observed at 440 nm. The laser damage threshold of the crystal was 0.6 GW/cm 2 at 532 nm. The second harmonic generation conversion efficiency of the powder sample of CDBA was found to be 4.5 times greater than that of urea. We also demonstrate the existence of the phase matching property in this crystal using Kurtz powder technique.

  14. Investigation on the linear and nonlinear optical properties of a metal organic complex—Bis thiourea zinc acetate single crystal

    Science.gov (United States)

    Pabitha, G.; Dhanasekaran, R.

    2013-09-01

    The third order nonlinear optical properties of bis thiourea zinc acetate single crystal were measured using He-Ne laser (λ=632.8nm) by employing the Z-scan technique. The magnitude of nonlinear refractive index and nonlinear absorption coefficient were found to be -2.11×10-8cm2/W and -1.201×10-3cm/W respectively. The linear refractive index of the complex was measured by the Brewster angle method and was found to be 1.483. The third order non-linear optical susceptibility χ(3) was found to be in the order of 10-6esu. The negative non-linear absorption coefficient shows the defocusing nature of the complex which is an essential property required for the application in optical limiting application. The second harmonic generation efficiency of the complex was studied using the Powder Kurtz method and was found to be 1.5 times greater than that of KDP.

  15. Synthesis, crystal structure, spectroscopic characterization and nonlinear optical properties of Co(II)- picolinate complex

    Energy Technology Data Exchange (ETDEWEB)

    Tamer, Ömer, E-mail: omertamer@sakarya.edu.tr; Avcı, Davut; Atalay, Yusuf

    2015-11-15

    A cobalt(II) complex of picolinate was synthesized, and its structure was fully characterized by the applying of X-ray diffraction method as well as FT-IR, FT-Raman and UV–vis spectroscopies. In order to both support the experimental results and convert study to more advanced level, density functional theory calculations were performed by using B3LYP level. Single crystal X-ray structural analysis shows that cobalt(II) ion was located to the center of distorted octahedral geometry. The C=O, C=C and C=N stretching vibrations were found as highly active and strong peaks, inducing the molecular charge transfer within Co(II) complex. The small energy gap between frontier molecular orbital energies was another indicator of molecular charge transfer interactions within Co(II) complex. The nonlinear optical properties of Co(II) complex were investigated at DFT/B3LYP level, and the hypepolarizability parameter was found to be decreased due to the presence of inversion symmetry. The natural bond orbital (NBO) analysis was performed to investigate molecular stability, hyperconjugative interactions, intramolecular charge transfer (ICT) and bond strength for Co(II) complex. Finally, molecular electrostatic potential (MEP) and spin density distributions for Co(II) complex were evaluated. - Highlights: • Co(II) complex of picolinate was prepared. • Its FT-IR, FT-Raman and UV–vis spectra were measured. • DFT calculations were performed to support experimental results. • Small HOMO-LUMO energy gap is an indicator of molecular charge transfer. • Spin density localized on Co(II) as well as O and N atoms.

  16. Generation of green frequency comb from chirped χ{sup (2)} nonlinear photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Lai, C.-M. [Department of Electronic Engineering, Ming Chuan University, Taoyuan, Taiwan (China); Chang, K.-H.; Yang, Z.-Y.; Fu, S.-H.; Tsai, S.-T.; Hsu, C.-W.; Peng, L.-H. [Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, Taiwan (China); Yu, N. E. [Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Boudrioua, A. [LPL, CNRS - UMR 7538, Université Paris 13, Sorbone Paris Cité (France); Kung, A. H. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan (China); Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan (China)

    2014-12-01

    Spectrally broad frequency comb generation over 510–555 nm range was reported on chirped quasi-phase-matching (QPM) χ{sup (2)} nonlinear photonic crystals of 12 mm length with periodicity stepwise increased from 5.9 μm to 7.1 μm. When pumped with nanosecond infrared (IR) frequency comb derived from a QPM optical parametric oscillator (OPO) and spanned over 1040 nm to 1090 nm wavelength range, the 520 nm to 545 nm up-converted green spectra were shown to consist of contributions from (a) second-harmonic generation among the signal or the idler modes, and (b) sum-frequency generation (SFG) from the neighboring pairs of the signal or the idler modes. These mechanisms led the up-converted green frequency comb to have the same mode spacing of 450 GHz as that in the IR-OPO pump comb. As the pump was further detuned from the aforementioned near-degeneracy point and moved toward the signal (1020–1040 nm) and the idler (1090–1110 nm) spectral range, the above QPM parametric processes were preserved in the chirped QPM devices to support up-converted green generation in the 510–520 nm and the 545–555 nm spectral regime. Additional 530–535 nm green spectral generation was also observed due to concurrence of multi-wavelength SFG processes between the (signal, idler) mode pairs. These mechanisms facilitate the chirped QPM device to support a single-pass up-conversion efficiency ∼10% when subject to an IR-OPO pump comb with 200 mW average power operated near- or off- the degeneracy point.

  17. Physicochemical properties of dimethylammonium p-nitrophenolate– p-nitrophenol: A nonlinear optical crystal

    Energy Technology Data Exchange (ETDEWEB)

    Rathika, A. [Department of Physics, Noorul Islam Centre for Higher Education, Noorul Islam University, Kumaracoil 629 180 (India); Prasad, L. Guru [Departemnt of Science & Humanities, M. Kumarasamy College of Engineering, Karur (India); Raman, R. Ganapathi, E-mail: ganapathiraman83@gmail.com [Department of Physics, Noorul Islam Centre for Higher Education, Noorul Islam University, Kumaracoil 629 180 (India)

    2016-03-15

    Single crystals of Dimethylammonium p-nitrophenolate–p-nitrophenol have been grown from aqueous solution by slow evaporation solution growth technique. Unit cell parameters of the grown crystal were confirmed by single crystal X-ray diffraction analysis and the synthesized compound is crystallized in monoclinic system. Various functional groups and their vibrational frequencies were recognized from the FT-IR and FT-Raman spectrum. Thermal stability of the crystal was examined by recording the TGA/DTA curve. The grown crystal has wider transparency nature in the visible region and the lower cut-off wavelength is found at 465 nm. Mechanical property of the crystal was studied by analyzing the Vicker's microhardness measurements. The fluorescence emission from the crystal is observed at 350 nm which arise due to the presence of aromatic ring. Relative SHG conversion efficiency of the grown crystal is about 0.59 times that of KDP.

  18. Physicochemical properties of dimethylammonium p-nitrophenolate- p-nitrophenol: A nonlinear optical crystal

    Science.gov (United States)

    Rathika, A.; Prasad, L. Guru; Raman, R. Ganapathi

    2016-03-01

    Single crystals of Dimethylammonium p-nitrophenolate-p-nitrophenol have been grown from aqueous solution by slow evaporation solution growth technique. Unit cell parameters of the grown crystal were confirmed by single crystal X-ray diffraction analysis and the synthesized compound is crystallized in monoclinic system. Various functional groups and their vibrational frequencies were recognized from the FT-IR and FT-Raman spectrum. Thermal stability of the crystal was examined by recording the TGA/DTA curve. The grown crystal has wider transparency nature in the visible region and the lower cut-off wavelength is found at 465 nm. Mechanical property of the crystal was studied by analyzing the Vicker's microhardness measurements. The fluorescence emission from the crystal is observed at 350 nm which arise due to the presence of aromatic ring. Relative SHG conversion efficiency of the grown crystal is about 0.59 times that of KDP.

  19. High pressure electrical resistivity study on nonlinear bis thiourea cadmium chloride (BTCC) single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Ariponnammal, S.; Radhika, S. [Department of Physics, Gandhigram Rural Institute, Deemed University, Gandhigram - 624 302, Dindigul District, Tamil Nadu (India); Selva Vennila, R. [Department of Physics, Anna University, Chennai - 600 025 (India); Arumugam, S. [Department of Physics, Bharathidasan University, Trichy (India)

    2005-09-01

    The Bis Thiourea Cadmium Chloride (BTCC) crystals have been crystallized by slow evaporation technique. The lattice parameters of the grown crystals have been determined by the Energy dispersive x-ray diffraction technique (EDXRD) and the structure has been confirmed. The high pressure electrical resistivity study have been carried out on this crystal and the results have been reported here. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. Growth of single crystals of organic salts with large second-order optical nonlinearities by solution processes for devices

    Science.gov (United States)

    Leslie, Thomas M.

    1995-01-01

    Data obtained from the electric field induced second harmonic generation (EFISH) and Kurtz Powder Methods will be provided to MSFC for further refinement of their method. A theoretical model for predicting the second-order nonlinearities of organic salts is being worked on. Another task is the synthesis of a number of salts with various counterions. Several salts with promising SHG activities and new salts will be tested for the presence of two crystalline forms. The materials will be recrystallized from dry and wet solvents and compared for SHG efficiency. Salts that have a high SHG efficiency and no tendency to form hydrates will be documented. The synthesis of these materials are included in this report. A third task involves method to aid in the growth of large, high quality single crystals by solution processes. These crystals will be characterized for their applicability in the fabrication of devices that will be incorporated into optical computers in future programs. Single crystals of optimum quality may be obtained by crystal growth in low-gravity. The final task is the design of a temperature lowering single crystal growth apparatus for ground based work. At least one prototype will be built.

  1. Studies on growth and characterization of a novel nonlinear optical and ferroelectric material - N,N-dimethylurea picrate single crystal

    Science.gov (United States)

    Shanthi, A.; Krishnan, C.; Selvarajan, P.

    2014-05-01

    A novel organic nonlinear optical (NLO) material viz. N,N-dimethylurea picrate (NNDMP) was grown by the slow evaporation technique using N,N-dimethyl formamide as a solvent. The solubility of the grown sample has been estimated for various temperatures. The XRD study reveals that the grown crystal crystallizes in the monoclinic crystal system and the corresponding lattice parameters were determined. The relative second harmonic generation (SHG) efficiency of the NNDMP was found to be 1.045 times that of KDP by Kurtz-Perry powder technique. FTIR and FT-Raman spectral analyses explain the various functional groups present in the sample. The optical spectral analysis of the grown crystal has been performed by UV-vis-NIR spectroscopy and the band gap energy was found out. The thermogravimetric analysis and differential thermal analysis (TG/DTA) reveal that the NNDMP crystal is stable at up to 172 °C. A prominent first-order ferroelectric to paraelectric phase transition at 323 K has been observed and activation energy was determined for the AC conduction process in the sample.

  2. Study of Growth, Structural, Thermal and Nonlinear Optical Properties of Silica Gel Grown Calcium Iodate Monohydrate Crystals

    Directory of Open Access Journals (Sweden)

    Sharda J. Shitole

    2015-12-01

    Full Text Available Single crystals of calcium iodate, monohydrate [Ca (IO32, H2O] were grown by simple gel technique by single and double diffusion method. Morphologies and habit faces like prismatic, prismatic pyramidal, needle shaped, hopper crystals were obtained. Few crystals were opaque, some were translucent and some good quality transparent crystals were obtained. EDAX spectrum verified that crystals are of calcium iodate, monohydrate indeed and was used to find Atomic % and Weight %. Unit cell parameters were obtained from the X-ray diffractogram. The calculated unit cell parameters, β, and‘d’ values are in good agreement with reported ones. Structural analysis was done by using FTIR spectroscopy which confirmed the presence of fundamental infrared frequencies, generally observed in all iodate compounds. Thermal analysis exhibits three steps explicitly on heating the samples. The first step involves dehydration at 5500C, second step shows decomposition at 5800C, and the third step involves again decomposition at 6400C. Powder second harmonic generation experiments exhibit the nonlinear nature of the substance.

  3. Integrated nonlinear optical imaging microscope for on-axis crystal detection and centering at a synchrotron beamline

    Energy Technology Data Exchange (ETDEWEB)

    Madden, Jeremy T.; Toth, Scott J.; Dettmar, Christopher M.; Newman, Justin A.; Oglesbee, Robert A.; Hedderich, Hartmut G.; Everly, R. Michael [Purdue University, 560 Oval Drive, West Lafayette, IN 47906 (United States); Becker, Michael [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Ronau, Judith A. [Purdue University, 560 Oval Drive, West Lafayette, IN 47906 (United States); Buchanan, Susan K. [National Institutes of Health, Building 50, Room 4503, 50 South Drive, Bethesda, MD 20814 (United States); Cherezov, Vadim [The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037 (United States); Morrow, Marie E. [Purdue University, 560 Oval Drive, West Lafayette, IN 47906 (United States); Xu, Shenglan; Ferguson, Dale; Makarov, Oleg [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Das, Chittaranjan [Purdue University, 560 Oval Drive, West Lafayette, IN 47906 (United States); Fischetti, Robert [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Simpson, Garth J., E-mail: gsimpson@purdue.edu [Purdue University, 560 Oval Drive, West Lafayette, IN 47906 (United States)

    2013-07-01

    Nonlinear optical (NLO) instrumentation has been integrated with synchrotron X-ray diffraction for combined single-platform analysis, examining the viability of NLO microscopy as an alternative to the conventional X-ray raster scan for the purposes of sample centering. Second-harmonic generation microscopy and two-photon excited ultraviolet fluorescence microscopy were evaluated for crystal detection, and assessed by X-ray raster scanning. Nonlinear optical (NLO) instrumentation has been integrated with synchrotron X-ray diffraction (XRD) for combined single-platform analysis, initially targeting applications for automated crystal centering. Second-harmonic-generation microscopy and two-photon-excited ultraviolet fluorescence microscopy were evaluated for crystal detection and assessed by X-ray raster scanning. Two optical designs were constructed and characterized; one positioned downstream of the sample and one integrated into the upstream optical path of the diffractometer. Both instruments enabled protein crystal identification with integration times between 80 and 150 µs per pixel, representing a ∼10{sup 3}–10{sup 4}-fold reduction in the per-pixel exposure time relative to X-ray raster scanning. Quantitative centering and analysis of phenylalanine hydroxylase from Chromobacterium violaceum cPAH, Trichinella spiralis deubiquitinating enzyme TsUCH37, human κ-opioid receptor complex kOR-T4L produced in lipidic cubic phase (LCP), intimin prepared in LCP, and α-cellulose samples were performed by collecting multiple NLO images. The crystalline samples were characterized by single-crystal diffraction patterns, while α-cellulose was characterized by fiber diffraction. Good agreement was observed between the sample positions identified by NLO and XRD raster measurements for all samples studied.

  4. Structural, optical, thermal and mechanical characterization of an organic nonlinear optical material: 4-methyl-3-nitrobenzoic acid single crystal

    Science.gov (United States)

    Bharathi, M. Divya; Ahila, G.; Mohana, J.; Chakkaravarthi, G.; Anbalagan, G.

    2016-11-01

    Organic single crystals of 4-methyl-3-nitrobenzoic acid (4M3N) have been grown by slow evaporation solution growth technique at room temperature. The single crystal X-ray diffraction study reveals that 4M3N crystallizes in monoclinic system with space group P21/n. The crystalline perfection of the crystal was analyzed by high resolution X-ray diffraction (HRXRD) measurements. The functional groups present in 4M3N have been identified from FT-IR and FT-Raman spectra. The lower cut-off wavelength of 4M3N is found to be 404 nm and the optical band gap is calculated as 2.91 eV. The refractive index shows normal behavior with wavelength. The physio chemical changes, decomposition and stability of the 4M3N compound were established by TG-DTA studies. Vickers microhardness measurement concludes that 4M3N belongs to soft material (n=2.5) category. The LDT value is found to be higher than that of KDP and some of the important organic NLO materials. The third order nonlinear refractive index and nonlinear absorption coefficient of the 4M3N have been measured by Z-scan studies. The imaginary and real parts of the third-order susceptibility values were determined as Im χ3=9.129×10-11 esu and Re χ3=1.4034×10-9 esu respectively. The dislocation density was calculated to be 3.0448×106 cm-2 which indicates the quality of the crystal.

  5. First-principles study of structure and nonlinear optical properties of CdHg(SCN)4 crystal

    Institute of Scientific and Technical Information of China (English)

    张鹏; 孔垂岗; 郑超; 王新强; 马跃; 冯金波; 矫玉秋; 卢贵武

    2015-01-01

    The geometric structure, electronic structure, and optical properties of CdHg(SCN)4 crystal are calculated by using the density functional perturbation theory and Green function screening Coulomb interaction approximation. The band gap of CdHg(SCN)4 crystal is calculated to be 3.198 eV, which is in good agreement with the experimental value 3.265 eV. The calculated second-order nonlinear optical coefficients are d14=1.2906 pm/V and d15=5.0928 pm/V, which are in agreement with the experimental results (d14=(1.4 ± 0.6) pm/V and d15=(6.0 ± 0.9) pm/V). Moreover, it is found that the contribution to the valence band mainly comes from Cd-4d, Hg-5d states, and the contributions to the valence band top and the conduction band bottom predominantly come from C-2p, N-2p, and S-3p states. The second-order nonlinear optical effect of CdHg(SCN)4 crystal results mainly from the internal electronic transition of (SCN)−.

  6. Effect of Metal Dopant on Ninhydrin—Organic Nonlinear Optical Single Crystals

    Directory of Open Access Journals (Sweden)

    R. S. Sreenivasan

    2013-01-01

    Full Text Available In the present work, metal (Cu2+-substituted ninhydrin single crystals were grown by slow evaporation method. The grown crystals have been subjected to single crystal XRD, powder X-ray diffraction, FTIR, dielectric and SHG studies. Single crystal X-ray diffraction analysis reveals that the compound crystallizes in monoclinic system with noncentrosymmetric space group P21 with lattice parameters a=11.28 Å, b=5.98 Å, c=5.71 Å, α=90∘, β=98.57, γ=90∘, and V=381 (Å3, which agrees very well with the reported value. The sharp and strong peaks in the powder X-ray diffraction pattern confirm the good crystallinity of the grown crystals. The presence of dopants marginally altered the lattice parameters without affecting the basic structure of the crystal. The UV-Vis transmittance spectrum shows that the crystal has a good optical transmittance in the entire visible region with lower cutoff wavelength 314 nm. The vibrational frequencies of various functional groups in the crystals have been derived from FT-IR analysis. Based on the shifts in the vibrations, the presence of copper in the lattice of the grown crystal is clearly established from the pure ninhydrin crystals. Both dielectric constant and dielectric loss decrease with the increase in frequency. The second harmonic generation efficiency was measured by employing powder Kurtz method.

  7. Study on third order nonlinear optical properties of a metal organic complex-Monothiourea-cadmium Sulphate Dihydrate single crystals grown in silica gel

    Science.gov (United States)

    Sivanandan, T.; Kalainathan, S.

    2015-04-01

    The third order nonlinear optical properties of Monothiourea-cadmium Sulphate Dihydrate crystal were measured using a He-Ne laser (λ=632.8 nm) by a Z-scan technique. The magnitude of nonlinear refractive index (n2) and nonlinear absorption coefficient was found to be 4.4769×10-11 m2/W and 1.233×10-2 m/W respectively. The third order non-linear optical susceptibility χ(3) was found to be in the order of 3.6533×10-2 esu. The negative sign of non-linear refractive index shows the self-defocusing nature of the gel grown crystal. The second-order molecular hyperpolarizability γ of the grown crystal is 1.2822×10-33 esu. Laser damage threshold was measured by using an Nd: YAG laser (1064 nm). Photoconductivity studies of the gel grown crystal revealed that the crystal possesses positive photoconducting nature. The results obtained from Z-scan, laser damage threshold and photoconducting studies reveal that the crystal can be a possible candidate material for photonics device, optical switches, and optical power limiting application.

  8. Coherence properties of supercontinuum generated in highly nonlinear photonic crystal fibers

    Science.gov (United States)

    Zhang, Yuji

    In this dissertation, experimentally measured spectral and coherence evolution of supercontinuum (SC) is presented. Highly nonlinear soft-glass photonic crystal fibers (PCF) were used for SC generation, including lead-silicate (Schott SF6) PCFs of a few different lengths: 10.5 cm, 4.7 mm, and 3.9 mm, and a tellurite PCF of 2.7 cm. The pump is an optical parametric oscillator (OPO) at 1550 nm with pulse energy in the order of nanojoule (nJ) and pulse duration of 105 femtosecond (fs). The coherence of SC was measured using the delayed-pulse method, where the interferometric signal was sent into an optical spectrum analyzer (OSA) and spectral fringes were recorded. By tuning the pump power, power-dependent evolution of spectrum and coherence was obtained. Numerical simulations based on the generalized nonlinear Schrodinger equation (GNLSE) were performed. To match the measured data, the simulated spectral evolution was optimized by iteratively tuning parameters and comparing features. To further match the simulated coherence evolution with the measurement, shot noise and pulse-to-pulse power fluctuation were added in the pump, and the standard deviation of the fluctuation was tuned. Good agreement was obtained between the simulated and the measured spectral evolution, in spite of the unavailability of some physical parameters for simulation. It is demonstrated in principle that, given a measured spectral evolution, the fiber length, and the average power of SC, all other parameters can be determined unambiguously, and the spectral evolution can be reproduced in the simulations. Most importantly, the soliton fission length can be simulated accurately. The spectral evolution using the 4.7- and the 3.9-mm SF6 PCFs shows a pattern dominated by self phase modulation (SPM). This indicates that, these fiber lengths are close to the soliton fission length at the maximum power. The spectral evolution using the 10.5-cm SF6 PCF and the 2.7-cm tellurite PCF shows a soliton

  9. Designing quadratic nonlinear photonic crystal fibers for soliton compression to few-cycle pulses

    DEFF Research Database (Denmark)

    Bache, Morten; Moses, Jeffrey; Lægsgaard, Jesper

    2007-01-01

    Second-harmonic generation (SHG) in the limit of large phase mismatch, given by Deltabeta=beta2-2beta1 effectively induces a Kerr-like nonlinear phase shift on the fundamental wave (FW). The phase mismatch determines the sign and magnitude of the effective Kerr nonlinearity, making large negative...

  10. Studies on 2-amino-5-nitropyridinium nitrate (2A5NPN): A semi-organic third order nonlinear optical single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Sivasubramani, V.; Pandian, Muthu Senthil, E-mail: senthilpandianm@ssn.edu.in; Ramasamy, P. [SSN Research Centre, SSN College of Engineering, Kalavakkam-603 110, Chennai, Tamilnadu (India)

    2016-05-23

    2-amino-5-nitropyridinium nitrate (2A5NPN) is a semi-organic nonlinear optical crystal and optically good quality 2A5NPN single crystals were successfully grown by slow evaporation solution growth technique (SEST) at ambient temperature. The crystallographic structure of the grown crystal was determined by single crystal X-Ray diffraction analysis and it belongs to Monoclinic crystal system with centro symmetric crystalline nature. The crystallinity of the grown crystal was confirmed by powder X-ray diffraction analysis. The other physical properties of grown crystals are also characterized using TG-DTA, UV-Visible NIR, chemical etching, photoconductivity and Z-scan measurements. The Z-scan method reveals that the 2A5NPN crystal possesses multi photon absorption behaviour and the significantly higher third order susceptibility and it is a promising potential NLO material.

  11. PREDICTION OF YIELD FUNCTIONS ON BCC POLYCRYSTALS

    Institute of Scientific and Technical Information of China (English)

    Huang Mojia; Fu Mingfu; Zheng Chaomei

    2006-01-01

    By the nonlinear optimization theory, we predict the yield function of single BCC crystals in Hill's criterion form. Then we give a formula on the macroscopic yield function of a BCC polycrystal Ω under Sachs' model, where the volume average of the yield functions of all BCC crystallites in Ω is taken as the macroscopic yield function of the BCC polycrystal. In constructing the formula, we try to find the relationship among the macroscopic yield function, the orientation distribution function (ODF), and the single BCC crystal's plasticity. An expression for the yield stress of a uniaxial tensile problem is derived under Taylor's model in order to compare the expression with that of the macroscopic yield function.

  12. A Sensitive Scheme to Observe Weak Photo-Refraction Effects in Some Nonlinear Optical Crystals Pumped by Ultrashort Optical Pulses

    Institute of Scientific and Technical Information of China (English)

    XU Shi-Xiang; GAO Yan-Xia; CAI Hua; LI Jing-Zhen

    2009-01-01

    We present a sensitive scheme, for the first time to our knowledge, to observe photo-refraction (PR) effects in some nonlinear optical crystals, e.g.β-BBO, LBO and BIBO, pumped by an intense ultrashort laser pulse chain. These quite weak effects are "amplified" by sensitive cw intracavity loss modulation. Our results show that they are repeatable and are dependent on pumping power and wavelength, and their response time ranges from tens of seconds to several minutes. The recorded dynamical transitions between the self-focusing to the self-defocusing (or vice versa) induced by the PR effect may be critically important for us to give more insight into the stability of some cascade nonlinear frequency conversions, e.g. multi-stage optical parametric amplifiers.

  13. Efficient continuous-wave nonlinear frequency conversion in high-Q Gallium Nitride photonic crystal cavities on Silicon

    CERN Document Server

    Mohamed, Mohamed Sabry; Carlin, Jean-François; Minkov, Momchil; Gerace, Dario; Savona, Vincenzo; Grandjean, Nicolas; Galli, Matteo; Houdré, Romuald

    2016-01-01

    We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave resonant excitation. Optimized two-dimensional PhC cavities with augmented far-field coupling have been characterized with quality factors as high as 4.4$\\times10^{4}$, approaching the computed theoretical values. The strong enhancement in light confinement has enabled efficient SHG, achieving normalized conversion efficiency of 2.4$\\times10^{-3}$ $W^{-1}$, as well as simultaneous THG. SHG emission power of up to 0.74 nW has been detected without saturation. The results herein validate the suitability of gallium nitride for integrated nonlinear optical processing.

  14. Synthesis, growth and characterization of a new nonlinear optical crystal: glycinium hydrogen squarate (GHS).

    Science.gov (United States)

    Paramasivam, P; Ramachandra Raja, C

    2012-07-01

    Single crystals of glycinium hydrogen squarate (GHS) have been successfully synthesized and purity of the material has been increased by repeated recrystallization process. Single crystals were grown by slow evaporation solution growth technique using water and ethanol as solvents at room temperature. Then the grown crystal was characterized by different techniques for finding its suitability for device fabrications. The grown crystal was characterized by single crystal XRD, powder XRD, FT-IR, UV-Vis-NIR, (1)H NMR, (13)C NMR, SHG and DTA/TGA analyses respectively. From the single crystal XRD diffraction, the crystal system was identified as monoclinic. The presence of functional groups were identified by FT-IR analysis. The UV transparency cut-off wavelength of the grown crystal occurs at 342nm. (1)H NMR and (13)C NMR spectroscopic studies were employed to elucidate the structure of the grown crystal. The second harmonic generation efficiency test by Kurtz-Perry technique showed positive result. The decomposition temperature of the grown crystal was studied by DTA/TGA analysis. The results observed from the characterization analyses show its suitability for NLO applications.

  15. Studies on the growth, spectral, structural, electrical, optical and mechanical properties of Uronium 3-carboxy-4-hydroxybenzenesulfonate single crystal for third-order nonlinear optical applications

    Science.gov (United States)

    Silambarasan, A.; Krishna Kumar, M.; Thirunavukkarasu, A.; Md Zahid, I.; Mohan Kumar, R.; Umarani, P. R.

    2015-05-01

    Organic Uronium 3-carboxy-4-hydroxybenzenesulfonate (UCHBS) nonlinear optical single crystal was grown by solution growth technique. The solubility and nucleation studies were performed for UCHBS at different temperatures 30, 35, 40, 45, 50 and 55 °C. The crystal structure of UCHBS was elucidated from single crystal X-ray diffraction study. High resolution X-ray diffraction technique was employed to study the perfection and internal defects of UCHBS crystal. Infrared and Raman spectra were recorded to analyze the vibrational behavior of chemical bonds and its functional groups. The physico-chemical changes, stability and decomposition stages of the UCHBS compound were established by TG-DTA studies. The dielectric phenomenon of UCHBS crystal was studied at different temperatures with respect to frequency. Linear optical properties of transmittance, cut-off wavelength, band gap of UCHBS were found from UV-visible spectral studies. Third-order nonlinear optical susceptibility, nonlinear refractive index, nonlinear optical absorption coefficient values were measured by Z-scan technique. The mechanical properties of UCHBS crystal was studied by using Vicker's microhardness test. The growth features of UCHBS crystal were analyzed from etching studies.

  16. Laser-induced breakdown and damage generation by nonlinear frequency conversion in ferroelectric crystals: Experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Center for Advanced Photonics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hatano, Hideki; Kitamura, Kenji [National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2013-11-28

    published for other nonlinear crystals and operated wavelengths.

  17. Mid-IR femtosecond frequency conversion by soliton-probe collision in phase-mismatched quadratic nonlinear crystals

    DEFF Research Database (Denmark)

    Liu, Xing; Zhou, Binbin; Guo, Hairun;

    2015-01-01

    in a quadratic nonlinear crystal (beta-barium borate) in the normal dispersion regime due to cascaded (phase-mismatched) second-harmonic generation, and the mid-IR converted wave is formed in the anomalous dispersion regime between. lambda = 2.2-2.4 mu m as a resonant dispersive wave. This process relies...... on nondegenerate four-wave mixing mediated by an effective negative cross-phase modulation term caused by cascaded soliton-probe sum-frequency generation. (C) 2015 Optical Society of America...

  18. Multi-Wavelength Erbium-Doped Fibre Lasers on Assistance of High-Nonlinear Photonic-Crystal Fibre

    Institute of Scientific and Technical Information of China (English)

    LIU Xue-Ming; ZHAO Wei; ZHANG Tong-Yi; LU Ke-Qing; SUN Chuan-Dong; WANG Yi-Shan; OUYANG Xian; HOU Xun; CHEN Guo-Fu

    2006-01-01

    @@ On the basis of self-stability effect of four-wave mixings (FWMs) in high-nonlinear photonic-crystal fibres, a novel multi-wavelength erbium-doped fibre (EDF)laser is proposed and demonstrated experimentally at room temperature. The proposed lasers have the capacity of switching and tuning with excellent uniformity and stability. By means of adjusting the attenuators, the triple-, four-, or five-wavelength EDF lasers can be lasing simultaneously.With the assistance of the FWM self-stability function, the multi-wavelength spectrum is excellently stabilized with uniformity less than 0.9dB.

  19. Evaluation of hydrogen-bonding distance in organic nonlinear optical crystals for high-output terahertz-wave generation

    Science.gov (United States)

    Matsukawa, Takeshi; Hoshikawa, Akinori; Ishikawa, Yoshihisa; Ishigaki, Toru

    2017-04-01

    The crystal structure of deuterated 4-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST-d26) was obtained by powder X-ray and neutron diffraction measurements. The scattering length density distributions of deuterium atoms were successfully obtained from neutron diffraction data using the maximum-entropy method. From the density distributions, we estimated the hydrogen-bonding distances, which contribute significantly to the vibrational modes of DAST at 1 THz. Inhibition of these hydrogen bonds could allow the development of new nonlinear optical materials with low THz absorption.

  20. Measurement of the Third-Order Nonlinear Optical Coefficient of ZnO Crystals by Using ICCD-Z-Scan

    Institute of Scientific and Technical Information of China (English)

    JIA Guang-Ming; ZHANG Gui-Zhong; XIANG Wang-Hua; J.B.Ketterson

    2004-01-01

    We present an image-intensified charge-coupled-device (ICCD) version of Z-scan by employing an ICCD detector and fixing the sample at the beam waist, and a measurement of the third-order nonlinear optical coefficient of single crystal zinc oxide (ZnO). The X(3) value of -9.1 × 10-15 cm2/W measured is in agreement with the published result. Our Z-scan configuration of placing sample at beam waist and collecting the whole wavefront by an ICCD detector is simple and can be deployed in cryogenic research where the sample cannot be Z-scanned.

  1. Growth and studies of cyclohexylammonium 4-methoxy benzoate single crystal for nonlinear optical applications

    Science.gov (United States)

    Sathya, P.; Gopalakrishnan, R.

    2015-06-01

    Cyclohexylammonium 4-Methoxy Benzoate (C4MB) was synthesised and the functional groups were confirmed by FTIR analysis. The purified C4MB (by repeated recrystallisation) was used for single crystal growth. Single crystal of cyclohexylammonium 4-methoxy benzoate was successfully grown by slow evaporation solution growth method at ambient temperature. Structural orientations were determined from single crystal X-ray diffractometer. Optical absorption and cut off wavelength were identified by UV-Visible spectroscopy. Thermal stability of the crystal was studied from thermogravimetric and differential thermal analyses curves. Mechanical stability of the grown crystal was analysed by Vicker's microhardness tester. The Second Harmonic Generation (SHG) study revealed that the C4MB compound exhibits the SHG efficiency 3.3 times greater than KDP crystal.

  2. Growth and studies of cyclohexylammonium 4-methoxy benzoate single crystal for nonlinear optical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sathya, P.; Gopalakrishnan, R., E-mail: krgkrishnan@annauniv.edu [Crystal Research Lab, Department of Physics, Anna University, Chennai-600002 (India)

    2015-06-24

    Cyclohexylammonium 4-Methoxy Benzoate (C4MB) was synthesised and the functional groups were confirmed by FTIR analysis. The purified C4MB (by repeated recrystallisation) was used for single crystal growth. Single crystal of cyclohexylammonium 4-methoxy benzoate was successfully grown by slow evaporation solution growth method at ambient temperature. Structural orientations were determined from single crystal X-ray diffractometer. Optical absorption and cut off wavelength were identified by UV-Visible spectroscopy. Thermal stability of the crystal was studied from thermogravimetric and differential thermal analyses curves. Mechanical stability of the grown crystal was analysed by Vicker’s microhardness tester. The Second Harmonic Generation (SHG) study revealed that the C4MB compound exhibits the SHG efficiency 3.3 times greater than KDP crystal.

  3. Spatiotemporal light bullets and supercontinuum generation in β-BBO crystal with competing quadratic and cubic nonlinearities.

    Science.gov (United States)

    Šuminas, R; Tamošauskas, G; Valiulis, G; Dubietis, A

    2016-05-01

    We experimentally study filamentation and supercontinuum generation in a birefringent medium [beta-barium borate (β-BBO) crystal] pumped by intense 90 fs, 1.8 μm laser pulses whose carrier wavelength falls in the range of anomalous group velocity dispersion of the crystal. We demonstrate that the competition between the intrinsic cubic and cascaded-quadratic nonlinearities may serve as a useful tool for controlling the self-action effects via phase matching condition. In particular, we found that spectral superbroadening of the ordinary polarization is linked to three-dimensional self-focusing and formation of self-compressed spatiotemporal light bullets that could be accessed within a certain range of either positive or negative phase mismatch. In the extraordinary polarization, we detect giant spectral shifts of the second harmonic radiation, which are attributed to a light bullet-induced self-phase matching.

  4. Thermal and Mechanical Properties of a Complex Nonlinear Optical Material: Cadmium Mercury Thiocyanate Crystal

    Institute of Scientific and Technical Information of China (English)

    YUAN Duo-Rong; XU Dong; ZHANG Guang-Hui; LIU Ming-Guo; GUO Shi-Yi; MENG Fan-Qing; LU Meng-Kai; FANG Qi; JIANG Min-Hua

    2000-01-01

    Institute of Crystal Materials and State Key Laboratory of Crystal Materials, Shandong University, Ji'nan 250100 (Received 18 March 2000) The data of the thermal expansion and specific heat of cadmium mercury thiocyanate crystal have been obtained. The specific heat is 0.7588J/g℃ at room temperature. The thermal expansion occurs in the direction parallel to the c-axis, and the thermal contraction occurs in the direction parallel to the a-axis. The thermal expansion is the same as the thermal contraction at 353 K. The relationship between thermal properties and crystal structure is discussed.

  5. Laser patterning of nonlinear optical Bi2ZnB2O7 crystal lines in glass

    Directory of Open Access Journals (Sweden)

    Takayuki eKomatsu

    2015-05-01

    Full Text Available Bi2O3-based glasses are very attractive from the viewpoints of low-melting, high refractive index and crystallization, and the research on their glasses and glass-ceramics is at the frontiers of glass science and technology. Nonlinear optical Bi2ZnB2O7 crystal lines with a high orientation were patterned in 3Sm2O3-30.3Bi2O3-33.3ZnO-33.3B2O3 glass by using a laser-induced crystallization technique. It was confirmed from transmission electron microscope observations that crystals were formed in the inside of the glass, i.e., at the beneath of 4 micro-meter from the surface, although lasers (Yb:YVO4 laser with a wavelength of 1080 nm were focused at the glass surface. A new potential for optical device applications was added in Bi2O3-based glasses from the present study.

  6. Ultrastable, high efficiency picosecond green light generation using K3B6O10Br series nonlinear optical crystals

    Science.gov (United States)

    Hou, Z. Y.; Xia, M. J.; Wang, L. R.; Xu, B.; Yan, D. X.; Meng, L. P.; Liu, L. J.; Xu, D. G.; Zhang, L.; Wang, X. Y.; Li, R. K.; Chen, C. T.

    2017-09-01

    Two perovskite-structure K3B6O10Br1-x Cl x (x  =  0 and 0.5) series nonlinear optical crystals were thoroughly investigated for their picosecond 532 nm laser pulses abilities and high power outputs were achieved via second harmonic generation (SHG) technique for the first time. SHG conversion efficiency of 57.3% with a 13.2 mm length K3B6O10Br (KBB) crystal was achieved using a laser source of pulse repetition rate of 10 Hz and pulse width of 25 ps, which is the highest conversion efficiency of ps visible laser based on KBB crystal. And by employing an 80 MHz, 10 ps fundamental laser beam, maximum power outputs of 12 W with K3B6O10Br0.5Cl0.5 (KBBC) and 11.86 W with KBB crystals were successfully demonstrated. Furthermore, the standard deviation jitters of the average power outputs are less than 0.6% and 1.17% by KBB and KBBC, respectively, showing ultrastable power stabilities favorable for practical applications. In addition, the other optical parameters including acceptance angle and temperature bandwidth were also investigated.

  7. The biaxial nonlinear crystal BiB3O6 as a polarization entangled photon source using non-collinear type-II parametric down-conversion

    CERN Document Server

    Halevy, A; Dovrat, L; Eisenberg, H S; Becker, P; Bohatý, L

    2011-01-01

    We describe the full characterization of the biaxial nonlinear crystal BiB3O6 (BiBO) as a polarization entangled photon source using non-collinear type-II parametric down-conversion. We consider the relevant parameters for crystal design, such as cutting angles, polarization of the photons, effective nonlinearity, spatial and temporal walk-offs, crystal thickness and the effect of the pump laser bandwidth. Experimental results showing entanglement generation with high rates and a comparison to the well investigated beta-BaB2O4 (BBO) crystal are presented as well. Changing the down-conversion crystal of a polarization entangled photon source from BBO to BiBO enhances the generation rate as if the pump power was increased by more than three times. Such an improvement is currently required for the generation of multiphoton entangled states.

  8. The biaxial nonlinear crystal BiB₃O₆ as a polarization entangled photon source using non-collinear type-II parametric down-conversion.

    Science.gov (United States)

    Halevy, A; Megidish, E; Dovrat, L; Eisenberg, H S; Becker, P; Bohatý, L

    2011-10-10

    We describe the full characterization of the biaxial nonlinear crystal BiB₃O₆ (BiBO) as a polarization entangled photon source using non-collinear type-II parametric down-conversion. We consider the relevant parameters for crystal design, such as cutting angles, polarization of the photons, effective nonlinearity, spatial and temporal walk-offs, crystal thickness and the effect of the pump laser bandwidth. Experimental results showing entanglement generation with high rates and a comparison to the well investigated β-BaB₂O₄ (BBO) crystal are presented as well. Changing the down-conversion crystal of a polarization entangled photon source from BBO to BiBO enhances the generation rate as if the pump power was increased by 2.5 times. Such an improvement is currently required for the generation of multiphoton entangled states.

  9. Measurement of nonlinear coefficients of crystals at terahertz frequencies via High Field THzat the FELIX FEL

    Science.gov (United States)

    2017-04-03

    Naftaly NPL MANAGEMENT LTD Final Report 04/02/2017 DISTRIBUTION A: Distribution approved for public release. AF Office Of Scientific Research (AFOSR)/ IOE...ADDRESS(ES) NPL MANAGEMENT LTD HAMPTON RD TEDDINGTON, TW11 0LW GB 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND...refractive index and () is the incident electric field. The imaginary component of nonlinear refractive index, i.e. nonlinear or multi-photon

  10. Switching Correlation and Noise Level in Pr3+:YSO Crystal via Dressing Nonlinear Phase

    OpenAIRE

    Irfan Ahmed; Zhaoyang Zhang; Feng Wen; Da Zhang; Changbiao Li; Ruimin Wang; Yanpeng Zhang

    2016-01-01

    We propose and experimentally demonstrate that the intensity noise correlation and the noise level of intensity-difference and intensity-sum in Stokes and anti-Stokes channel can be well controlled by the relative nonlinear phase in spontaneous parametric four-wave mixing process. By modulating the relative nonlinear phase, including self-phase modulation and cross-phase modulation, switching the correlation into anti-correlation and the relative intensity noise level between the intensity-di...

  11. Tuning quadratic nonlinear photonic crystal fibers for zero group-velocity mismatch

    DEFF Research Database (Denmark)

    Bache, Morten; Lægsgaard, Jesper; Bang, Ole

    2006-01-01

    A nonlinear index-guiding silica PCF is optimized for efficient second-harmonic generation through dispersion calculations. Zero group-velocity mismatch is possible for any pump wavelength above 780 nm. Very high conversion efficiencies and bandwidths are found.......A nonlinear index-guiding silica PCF is optimized for efficient second-harmonic generation through dispersion calculations. Zero group-velocity mismatch is possible for any pump wavelength above 780 nm. Very high conversion efficiencies and bandwidths are found....

  12. Concept for power scaling second harmonic generation using a cascade of nonlinear crystals

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Tawfieq, Mahmoud; Jensen, Ole Bjarlin;

    2015-01-01

    Within the field of high-power second harmonic generation (SHG), power scaling is often hindered by adverse crystal effects such as thermal dephasing arising from the second harmonic (SH) light, which imposes limits on the power that can be generated in many crystals. Here we demonstrate a concept...

  13. Modeling dependence structure between stock market volatility and sukuk yields: A nonlinear study in the case of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Nader Naifar

    2016-09-01

    Full Text Available The aim of this paper is to investigate the dependence structure between sukuk (Islamic bonds yields and stock market (returns and volatility in the case of Saudi Arabia. We consider three Archimedean copula models with different tail dependence structures namely Gumbel, Clayton, and Frank. This study shows that the sukuk yields exhibit significant dependence only with stock market volatility. In addition, the dependence structure between sukuk yields and stock market volatility are symmetric and linked with the same intensity.

  14. Interface and facet control during Czochralski growth of (111) InSb crystals for cost reduction and yield improvement of IR focal plane array substrates

    Science.gov (United States)

    Gray, Nathan W.; Perez-Rubio, Victor; Bolke, Joseph G.; Alexander, W. B.

    2014-10-01

    Focal plane arrays (FPAs) made on InSb wafers are the key cost-driving component in IR imaging systems. The electronic and crystallographic properties of the wafer directly determine the imaging device performance. The "facet effect" describes the non-uniform electronic properties of crystals resulting from anisotropic dopant segregation during bulk growth. When the segregation coefficient of dopant impurities changes notably across the melt/solid interface of a growing crystal the result is non-uniform electronic properties across wafers made from these crystals. The effect is more pronounced in InSb crystals grown on the (111) axis compared with other orientations and crystal systems. FPA devices made on these wafers suffer costly yield hits due to inconsistent device response and performance. Historically, InSb crystal growers have grown approximately 9-19 degree off-axis from the (111) to avoid the facet effect and produced wafers with improved uniformity of electronic properties. It has been shown by researchers in the 1960s that control of the facet effect can produce uniform small diameter crystals. In this paper, we share results employing a process that controls the facet effect when growing large diameter crystals from which 4, 5, and 6" wafers can be manufactured. The process change resulted in an increase in wafers yielded per crystal by several times, all with high crystal quality and uniform electronic properties. Since the crystals are grown on the (111) axis, manufacturing (111) oriented wafers is straightforward with standard semiconductor equipment and processes common to the high-volume silicon wafer industry. These benefits result in significant manufacturing cost savings and increased value to our customers.

  15. Studies on the growth aspects, structural, thermal, dielectric and third order nonlinear optical properties of solution grown 4-methylpyridinium p-nitrophenolate single crystal

    Science.gov (United States)

    Devi, S. Reena; Kalaiyarasi, S.; Zahid, I. MD.; Kumar, R. Mohan

    2016-11-01

    An ionic organic optical crystal of 4-methylpyridinium p-nitrophenolate was grown from methanol by slow evaporation method at ambient temperature. Powder and single crystal X-ray diffraction studies revealed the crystal system and its crystalline perfection. The rocking curve recorded from HRXRD study confirmed the crystal quality. FTIR spectral analysis confirmed the functional groups present in the title compound. UV-visible spectral study revealed the optical window and band gap of grown crystal. The thermal, electrical and surface laser damage threshold properties of harvested crystal were examined by using TGA/DTA, LCR/Impedance Analyzer and Nd:YAG laser system respectively. The third order nonlinear optical property of grown crystal was elucidated by Z-scan technique.

  16. Development of an ultra-widely tunable DFG-THz source with switching between organic nonlinear crystals pumped with a dual-wavelength BBO optical parametric oscillator.

    Science.gov (United States)

    Notake, Takashi; Nawata, Kouji; Kawamata, Hiroshi; Matsukawa, Takeshi; Qi, Feng; Minamide, Hiroaki

    2012-11-01

    We developed a difference frequency generation (DFG) source with an organic nonlinear optical crystal of DAST or BNA selectively excited by a dual-wavelength β-BaB(2)O(4) optical parametric oscillator (BBO-OPO). The dual-wavelength BBO-OPO can independently oscillate two lights with different wavelengths from 800 to 1800 nm in a cavity. THz-wave generation by using each organic crystal covers ultrawide range from 1 to 30 THz with inherent intensity dips by crystal absorption modes. The reduced outputs can be improved by switching over the crystals with adequately tuned pump wavelengths of the BBO-OPO.

  17. Experimental study of supercontinuum generation in an amplifier based on an Yb3+ doped nonlinear photonic crystal fiber

    Science.gov (United States)

    Baselt, Tobias; Taudt, Christopher; Nelsen, Bryan; Lasagni, Andrés. Fabián.; Hartmann, Peter

    2016-03-01

    The use of supercontinuum light sources in different optical measurement methods, like microscopy or optical coherence tomography, has increased significantly compared to classical wideband light sources. The development of various optical measurement techniques benefits from the high brightness and bandwidth, as well as the spatial coherence of these sources. For some applications, only a portion of the broad spectral range can be used. Therefore, an increase of the spectral power density in limited spectral regions would provide a clear advantage over spectral filtering. This study describes a method to increase the spectral power density of supercontinuum sources by amplifying the excitation wavelength inside a nonlinear photonic crystal fiber (PCF). An ytterbium doped photonic crystal fiber was manufactured by a sol-gel process and used in a fiber amplifier setup as the nonlinear fiber medium. In order to characterize the fiber's optimum operational characteristics, group-velocity dispersion (GVD) measurements were performed on the fiber during the amplification process. For this purpose, a notch-pass mirror was used to launch the radiation of a stabilized laser diode at 976 nm into the fiber sample for pumping. The performance of the fiber was compared with a conventional PCF. Finally, the system as a whole was characterized in reference to common solid state-laser-based photonic supercontinuum light sources. An improvement of the power density up to 7.2 times was observed between 1100 nm to 1380 nm wavelengths.

  18. Plasmonic enhancement of second harmonic generation from nonlinear RbTiOPO4 crystals by aggregates of silver nanostructures

    DEFF Research Database (Denmark)

    Sánchez-García, Laura; Tserkezis, Christos; Ramírez, Mariola O;

    2016-01-01

    We demonstrate a 60–fold enhancement of the second harmonic generation (SHG) response at the nanoscale in a hybrid metal-dielectric system. By using complex silver nanostructures photochemically deposited on the polar surface of a ferroelectric crystal, we tune the plasmonic resonances from the v...... the potential of aggregates of silver nanostructures for enhancing optical nonlinearities at the nanoscale and provides an alternative approach for the development of nanometric nonlinear photonic devices in a scalable way.......We demonstrate a 60–fold enhancement of the second harmonic generation (SHG) response at the nanoscale in a hybrid metal-dielectric system. By using complex silver nanostructures photochemically deposited on the polar surface of a ferroelectric crystal, we tune the plasmonic resonances from...... or up to 60 times when it matches the fundamental NIR radiation. The results are consistent with the more spatially-extended near-field response of complex metallic nanostructures and can be well explained by taking into account the quadratic character of the SHG process. The work points out...

  19. Growth, spectral, linear and nonlinear optical characteristics of an efficient semiorganic acentric crystal: L-valinium L-valine chloride

    Science.gov (United States)

    Nageshwari, M.; Jayaprakash, P.; Kumari, C. Rathika Thaya; Vinitha, G.; Caroline, M. Lydia

    2017-04-01

    An efficient nonlinear optical semiorganic material L-valinium L-valine chloride (LVVCl) was synthesized and grown-up by means of slow evaporation process. Single crystal XRD evince that LVVCl corresponds to monoclinic system having acentric space group P21. The diverse functional groups existing in LVVCl were discovered with FTIR spectral investigation. The UV-Visible and photoluminescence spectrum discloses the optical and electronic properties respectively for the grown crystal. Several optical properties specifically extinction coefficient, reflectance, linear refractive index, electrical and optical conductivity were also determined. The SEM analysis was also carried out and it portrayed the surface morphology of LVVCl. The calculated value of laser damage threshold was 2.59 GW/cm2. The mechanical and dielectric property of LVVCl was investigated employing microhardness and dielectric studies. The second and third order nonlinear optical characteristics of LVVCl was characterized utilizing Kurtz Perry and Z scan technique respectively clearly suggest its suitability in the domain of optics and photonics.

  20. All-optical transistor- and diode-action and logic gates based on anisotropic nonlinear responsive liquid crystal.

    Science.gov (United States)

    Wang, Cheng-Yu; Chen, Chun-Wei; Jau, Hung-Chang; Li, Cheng-Chang; Cheng, Chiao-Yu; Wang, Chun-Ta; Leng, Shi-Ee; Khoo, Iam-Choon; Lin, Tsung-Hsien

    2016-08-05

    In this paper, we show that anisotropic photosensitive nematic liquid crystals (PNLC) made by incorporating anisotropic absorbing dyes are promising candidates for constructing all-optical elements by virtue of the extraordinarily large optical nonlinearity of the nematic host. In particular, we have demonstrated several room-temperature 'prototype' PNLC-based all-optical devices such as optical diode, optical transistor and all primary logic gate operations (OR, AND, NOT) based on such optical transistor. Owing to the anisotropic absorption property and the optical activity of the twist alignment nematic cell, spatially non-reciprocal transmission response can be obtained within a sizeable optical isolation region of ~210 mW. Exploiting the same mechanisms, a tri-terminal configuration as an all-optical analogue of a bipolar junction transistor is fabricated. Its ability to be switched by an optical field enables us to realize an all-optical transistor and demonstrate cascadability, signal fan-out, logic restoration, and various logical gate operations such as OR, AND and NOT. Due to the possibility of synthesizing anisotropic dyes and wide ranging choice of liquid crystals nonlinear optical mechanisms, these all-optical operations can be optimized to have much lower thresholds and faster response speeds. The demonstrated capabilities of these devices have shown great potential in all-optical control system and photonic integrated circuits.

  1. Stokes polarimetry using analysis of the nonlinear voltage-retardance relationship for liquid-crystal variable retarders

    Energy Technology Data Exchange (ETDEWEB)

    López-Téllez, J. M., E-mail: jmlopez@comunidad.unam.mx; Bruce, N. C. [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad Universitaria, Apdo. Postal 70-186, México D.F., 04510 (Mexico)

    2014-03-15

    We present a method for using liquid-crystal variable retarders (LCVR’s) with continually varying voltage to measure the Stokes vector of a light beam. The LCVR's are usually employed with fixed retardance values due to the nonlinear voltage-retardance behavior that they show. The nonlinear voltage-retardance relationship is first measured and then a linear fit of the known retardance terms to the detected signal is performed. We use known waveplates (half-wave and quarter-wave) as devices to provide controlled polarization states to the Stokes polarimeter and we use the measured Stokes parameters as functions of the orientation of the axes of the waveplates as an indication of the quality of the polarimeter. Results are compared to a Fourier analysis method that does not take into account the nonlinear voltage-retardance relationship and also to a Fourier analysis method that uses experimental voltage values to give a linear retardance function with time. Also, we present results of simulations for comparison.

  2. Stokes polarimetry using analysis of the nonlinear voltage-retardance relationship for liquid-crystal variable retarders.

    Science.gov (United States)

    López-Téllez, J M; Bruce, N C

    2014-03-01

    We present a method for using liquid-crystal variable retarders (LCVR's) with continually varying voltage to measure the Stokes vector of a light beam. The LCVR's are usually employed with fixed retardance values due to the nonlinear voltage-retardance behavior that they show. The nonlinear voltage-retardance relationship is first measured and then a linear fit of the known retardance terms to the detected signal is performed. We use known waveplates (half-wave and quarter-wave) as devices to provide controlled polarization states to the Stokes polarimeter and we use the measured Stokes parameters as functions of the orientation of the axes of the waveplates as an indication of the quality of the polarimeter. Results are compared to a Fourier analysis method that does not take into account the nonlinear voltage-retardance relationship and also to a Fourier analysis method that uses experimental voltage values to give a linear retardance function with time. Also, we present results of simulations for comparison.

  3. Design of an As2Se3-based photonic quasi-crystal fiber with highly nonlinear and dual zero-dispersion wavelengths

    Science.gov (United States)

    Zhao, Tongtong; Lou, Shuqin; Su, Wei; Wang, Xin

    2016-01-01

    We propose an As2Se3-based highly nonlinear photonic quasi-crystal fiber with dual zero-dispersion wavelengths (ZDWs). Using a full-vector finite element method, the proposed fiber is optimized to obtain high nonlinear coefficient, low confinement loss and two zero-dispersion points by optimizing the structure parameters. Numerical results demonstrate that the proposed photonic quasi-crystal fiber (PQF) has dual ZDWs and the nonlinear coefficient up to 2600 W-1 km-1 within the wavelength range from 2 to 5.5 μm. Due to the introduction of the large air holes in the third ring of the proposed fiber, the ability of confining the fundamental mode field can be improved effectively and thus the low confinement loss can be obtained. The proposed PQF with high nonlinearity and dual ZDWs will have a number of potential applications in four-wave mixing, super-continuum generation, and higher-order dispersion effects.

  4. Growth, spectral, optical, thermal, surface analysis and third order nonlinear optical properties of an organic single crystal: 1-(2-Methyl-6-nitro-4-phenyl-3-quinolyl) ethanone.

    Science.gov (United States)

    Nirosha, M; Kalainathan, S; Sarveswari, S; Vijayakumar, V; Srikanth, A

    2015-02-25

    Single crystal of 1-(2-Methyl-6-nitro-4-phenyl-3-quinolyl) ethanone was grown using slow evaporation solution growth technique. Single crystal X-ray diffraction study reveals the lattice parameters of the grown crystal. The modes of vibration of different molecular groups present in 2M6NQE were identified by FTIR spectral analysis. Its optical behavior was examined through UV-vis-NIR absorption and PL emission spectrum. They signify that the crystal has transparency in the region between 383 and 1100 nm. The PL spectrum of the title compound shows green emission in the crystal. From the thermal analysis, 2M6NQE has found to be thermally stable up to 263°C, and the melting point of the material is 170°C. The estimations of third order non-linear optical properties like non-linear absorption coefficient (β), non-linear refractive index (n2) and susceptibility [χ(3)] were calculated using Z-scan technique. It has observed that, crystal exhibits reverse saturation absorption and self-defocusing performance. Etching study was carried out for the grown crystal using different solvents. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Growth and characterization of an organic nonlinear optical material—lauric acid crystal

    Science.gov (United States)

    Maheswari, J. Uma; Krishnan, C.; Kalyanaraman, S.; Selvarajan, P.

    2016-10-01

    Single crystals of pure lauric acid (LA) were harvested from ethanol solution by a slow evaporation technique. X-ray diffraction showed that the LA crystallized in the monoclinic system and was used to determine the lattice parameters. The Kurtz-Perry powder technique showed that the second-harmonic generation efficiency of LA was 0.87 times that of potassium dihydrogen phosphate. Fourier transform infrared spectral analysis was used to identify the various fatty acid functional groups present in the sample. Thermogravimetric analysis and differential thermal analysis revealed that the LA crystal is stable up to 45 °C. The mechanical strength of the sample crystal was estimated by the Vickers hardness test. Impedance analysis was carried out for the sample at different frequencies and a Nyquist plot was drawn to understand the electrical properties.

  6. Switching Correlation and Noise Level in Pr(3+):YSO Crystal via Dressing Nonlinear Phase.

    Science.gov (United States)

    Ahmed, Irfan; Zhang, Zhaoyang; Wen, Feng; Zhang, Da; Li, Changbiao; Wang, Ruimin; Zhang, Yanpeng

    2016-09-21

    We propose and experimentally demonstrate that the intensity noise correlation and the noise level of intensity-difference and intensity-sum in Stokes and anti-Stokes channel can be well controlled by the relative nonlinear phase in spontaneous parametric four-wave mixing process. By modulating the relative nonlinear phase, including self-phase modulation and cross-phase modulation, switching the correlation into anti-correlation and the relative intensity noise level between the intensity-difference and intensity-sum are realized. We also show that the variation tendencies of the relative intensity noise level and the corresponding intensity fluctuations correlation are in accordance with each other.

  7. Synthesis, X-ray crystal structure and highly non-linear optical properties of inorganic-organic hybrid compound: 1,4-Diazbicyclo-octane oxonium tri- nitrates single crystal

    Science.gov (United States)

    Henchiri, Rokaya; Ennaceur, Nasreddine; Cordier, Marie; Ledoux-Rak, Isabelle; Elaloui, Elimame

    2017-07-01

    A new nonlinear optical hybrid crystal 1,4-Diazbicyclo[222]octane oxonium tri-nitrates (DOTN), of the dimension 4×12×1 mm3. The crystal was grown using water as solvent at room temperature and crystal structure was determined by X-Ray diffraction respectively, this title compound was shown to crystallize in non-centrosymmetric trigonal system with space group P31c. The recorded FTIR spectrum has proven the presence of various functional groups in the grown crystal as well as the formation of DOTN. Besides, the thermal stability and melting temperature of the DOTN crystal were identified from the TG/DSC analysis. The suitability of this material for optical application was studied by non-linear optical (NLO) and UV-visible absorption techniques. Furthermore, the nonlinear optical property was analyzed by Kurtz-Perry powder technique and was 3.4 times than that of KDP (potassium dihydrogen phosphate) single crystals. The first hyperpolarizability of nitrate was determined by Second Harmonic light Scattering.

  8. Laue crystal structure of Shewanella oneidensis cytochrome c nitrite reductase from a high-yield expression system

    Energy Technology Data Exchange (ETDEWEB)

    Youngblut, Matthew; Judd, Evan T.; Srajer, Vukica; Sayyed, Bilal; Goelzer, Tyler; Elliott, Sean J.; Schmidt, Marius; Pacheco, A. Andrew (UW); (UC); (BU)

    2012-09-11

    The high-yield expression and purification of Shewanella oneidensis cytochrome c nitrite reductase (ccNiR) and its characterization by a variety of methods, notably Laue crystallography, are reported. A key component of the expression system is an artificial ccNiR gene in which the N-terminal signal peptide from the highly expressed S. oneidensis protein 'small tetraheme c' replaces the wild-type signal peptide. This gene, inserted into the plasmid pHSG298 and expressed in S. oneidensis TSP-1 strain, generated approximately 20 mg crude ccNiR per liter of culture, compared with 0.5-1 mg/L for untransformed cells. Purified ccNiR has nitrite and hydroxylamine reductase activities comparable to those previously reported for Escherichia coli ccNiR, and is stable for over 2 weeks in pH 7 solution at 4 C. UV/vis spectropotentiometric titrations and protein film voltammetry identified five independent one-electron reduction processes. Global analysis of the spectropotentiometric data also allowed determination of the extinction coefficient spectra for the five reduced ccNiR species. The characteristics of the individual extinction coefficient spectra suggest that, within each reduced species, the electrons are distributed among the various hemes, rather than being localized on specific heme centers. The purified ccNiR yielded good-quality crystals, with which the 2.59-{angstrom}-resolution structure was solved at room temperature using the Laue diffraction method. The structure is similar to that of E. coli ccNiR, except in the region where the enzyme interacts with its physiological electron donor (CymA in the case of S. oneidensis ccNiR, NrfB in the case of the E. coli protein).

  9. Optical Sampling at 80 Gbit/s Using a Highly Non-Linear Photonic Crystal Fiber

    Institute of Scientific and Technical Information of China (English)

    Andrea Tersigni; Vanessa Calle; Anders Clausen; Palle Jeppesen; Kim P. Hansen; Jacob R. Folkenberg

    2003-01-01

    Optical sampling using four-wave mixing in 50m of newly developed highly non-linear photo niccrystal fiber has been achieved at 80 Gbit/s with an Extinction Ratio of 12 dB. A basic characterization is also included.

  10. Nonlinear optical response of the collagen triple helix and second harmonic microscopy of collagen liquid crystals

    Science.gov (United States)

    Deniset-Besseau, A.; De Sa Peixoto, P.; Duboisset, J.; Loison, C.; Hache, F.; Benichou, E.; Brevet, P.-F.; Mosser, G.; Schanne-Klein, M.-C.

    2010-02-01

    Collagen is characterized by triple helical domains and plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. Remarkably, fibrillar collagen exhibits efficient Second Harmonic Generation (SHG) and SHG microscopy proved to be a sensitive tool to score fibrotic pathologies. However, the nonlinear optical response of fibrillar collagen is not fully characterized yet and quantitative data are required to further process SHG images. We therefore performed Hyper-Rayleigh Scattering (HRS) experiments and measured a second order hyperpolarisability of 1.25 10-27 esu for rat-tail type I collagen. This value is surprisingly large considering that collagen presents no strong harmonophore in its amino-acid sequence. In order to get insight into the physical origin of this nonlinear process, we performed HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro-Gly)10]3. It showed that the collagen large nonlinear response originates in the tight alignment of a large number of weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal along the triple helix. To illustrate this mechanism, we successfully recorded SHG images in collagen liquid solutions by achieving liquid crystalline ordering of the collagen triple helices.

  11. An investigation of doubly-resonant optical parametric oscillators and nonlinear crystals for squeezing

    NARCIS (Netherlands)

    Stefszky, Michael; Mow-Lowry, Conor M.; McKenzie, Kirk; Chua, Sheon; Buchler, Ben C.; Symul, Thomas; McClelland, David E.; Lam, Ping Koy

    2011-01-01

    A squeezed light source requires properties such as high squeezing amplitude, high bandwidth and stability over time, ideally using as few resources, such as laser power, as possible. We compare three nonlinear materials, two of which have not been well characterized for squeezed state production,

  12. An investigation of doubly-resonant optical parametric oscillators and nonlinear crystals for squeezing

    NARCIS (Netherlands)

    Stefszky, Michael; Mow-Lowry, Conor M.; McKenzie, Kirk; Chua, Sheon; Buchler, Ben C.; Symul, Thomas; McClelland, David E.; Lam, Ping Koy

    2011-01-01

    A squeezed light source requires properties such as high squeezing amplitude, high bandwidth and stability over time, ideally using as few resources, such as laser power, as possible. We compare three nonlinear materials, two of which have not been well characterized for squeezed state production, a

  13. Crystal structure, optical and thermal studies of a new organic nonlinear optical material: L-Histidinium maleate 1.5-hydrate

    Energy Technology Data Exchange (ETDEWEB)

    Gonsago, C. Alosious [Department of Physics, A. J. College of Engineering, Chennai 603103 (India); Albert, Helen Merina [Department of Physics, Sathyabama University, Chennai 600119 (India); Karthikeyan, J. [Department of Chemistry, Sathyabama University, Chennai 600119 (India); Sagayaraj, P. [Department of Physics, Loyola College, Chennai 600034 (India); Pragasam, A. Joseph Arul, E-mail: drjosephsu@gmail.com [Department of Physics, Sathyabama University, Chennai 600119 (India)

    2012-07-15

    Highlights: ► L-Histidinium maleate 1.5-hydrate, a new organic crystal has been grown for the first time. ► The crystal structure is reported for the first time (CCDC 845975). ► The crystal belongs to monoclinic system with space group P2{sub 1}, Z = 4, a = 11.4656(7) Å, b = 8.0530(5) Å, c = 14.9705(9) Å and β = 101.657(2)°. ► The optical absorption study substantiates the complete transparency of the crystal. ► Kurtz powder SHG test confirms the nonlinear property of the crystal. -- Abstract: A new organic nonlinear optical material L-histidinium maleate 1.5-hydrate (LHM) with the molecular formula C{sub 10}H{sub 16}N{sub 3}O{sub 7.5} has been successfully synthesized from aqueous solution by slow solvent evaporation method. The structural characterization of the grown crystal was carried out by single crystal X-ray diffraction at 293(2) K. In the crystal, molecules are linked through inter and intramolecular N-H⋯O and O-H⋯O hydrogen bonds, generate edge fused ring motif. The hydrogen bonded motifs are linked to each other to form a three dimensional network. The FT-IR spectroscopy was used to identify the functional groups of the synthesized compound. The optical behavior of the grown crystal was examined by UV–visible spectral analysis, which shows that the optical absorption is almost negligible in the wavelength range 280–1300 nm. The nonlinear optical property was confirmed by the powder technique of Kurtz and Perry. The thermal behavior of the grown crystal was analyzed by thermogravimetric analysis.

  14. Studies on the growth aspects, structural and third-order nonlinear optical properties of Piperidinium 3-carboxy-4-hydroxy benzenesulfonate single crystal

    Science.gov (United States)

    Kalaiyarasi, S.; Zahid, I. MD; Devi, S. Reena; Kumar, R. Mohan

    2017-02-01

    Organic nonlinear optical material Piperidinium 3-carboxy-4-hydroxy benzenesulfonate (PBS) single crystal was successfully grown by solution growth method. Single crystal X-ray diffraction study confirms that, the grown crystal belongs to P21/n space group. The crystalline quality of PBS was ascertained by HRXRD studies. Infrared spectral analysis showed the vibrational behaviour of chemical bonds and presence of its functional groups. TG/DTA studies were used to study the thermal stability and decomposition stages of the compound. UV-visible transmittance studies showed the transparency region, cut-off wavelength and band gap of the grown crystal. Photoluminescence emission study was carried out for the grown crystal to show its electronic properties. By using Nd:YAG laser, the laser damage threshold was estimated for the grown crystal. The third-order nonlinear optical parameters of the grown crystal were estimated by Z-scan technique using He-Ne laser source. The mechanical property of the PBS crystal was studied by using Vicker's microhardness measurement.

  15. AC and DC Electrical Conductivity Measurements on Glycine Family of Nonlinear Optical (NLO Single Crystals

    Directory of Open Access Journals (Sweden)

    Suresh Sagadevan

    2014-04-01

    Full Text Available In the present work, the AC/DC conductivity studies were carried out on Glycine family of NLO single crystals such as Trisglycine Zinc Chloride (TGZC, Triglycine Acetate (TGAc and Glycine Lithium Sulphate (GLS. The AC conductivity measurements were carried out using HIOKI 3532-50 LCR HITESTER in the frequency range of 50 Hz to 5 MHz for the grown NLO single crystals. The DC electrical conductivity measurements were also carried out for the crystals using the conventional two – probe technique in the temperature range of 313 – 423 K. The present study indicates that both the AC and DC conductivity of the samples increase with the increase in temperature. The activation energies were also calculated from AC/DC conductivity studies.

  16. Structure and nonlinear optical properties of (E)-1-(4-aminophenyl)-3-(3-chlorophenyl) prop-2-en-1-one: A promising new D-π-A-π-D type chalcone derivative crystal for nonlinear optical devices

    Science.gov (United States)

    Ekbote, Anusha; Patil, P. S.; Maidur, Shivaraj R.; Chia, Tze Shyang; Quah, Ching Kheng

    2017-02-01

    In this paper, we present the structure and nonlinear optical (NLO) studies of a D-π-A-π-D type chalcone derivative, (E)-1-(4-aminophenyl)-3-(3-chlorophenyl) prop-2-en-1-one (abbreviated as 3CAMC). The compound was synthesized by Claisen-Schmidt condensation and single crystals were grown by slow evaporation solution growth technique. The structure was confirmed by FT-IR, 1H NMR and single-crystal X-ray diffraction techniques. The 3CAMC crystal is crystallized in the monoclinic crystal system with non-centrosymmetric space group P21 with the unit cell parameters a = 8.0013 (19) Å, b = 4.6630 (11) Å, c = 16.883 (4) Å, β = 95.568 (3)° and Z = 2. The optical absorption spectrum was recorded using UV-Vis-NIR spectrophotometer and the band gap was calculated. The title crystal has a direct band gap of 2.96 eV. TGA/DTA thermal analysis revealed that the crystal has a good thermal stability. The second harmonic generation (SHG) efficiency was investigated using the modified Kurtz-Perry powder test at 1064 nm wavelength with nanosecond (ns) laser pulses. The SHG efficiency is found to be 7 times higher than the well-studied urea. The third-order nonlinear optical properties of 3CAMC at different concentrations were investigated in DMF using Z-scan technique with continuous wave (CW) DPSS laser at 532 nm wavelength. The molecule shows a strong two-photon absorption (2PA) and significant negative nonlinear refraction characteristic (self-defocusing) in the CW regime. Further, we observed the optical limiting behavior in the compound, and evaluated the one-photon and two-photon figures of merit. The encouraging results of NLO studies suggest that the 3CAMC crystal is a promising material for photonics devices, optical switches, and optical power limiting applications.

  17. Non-linear mixing in coupled photonic crystal nanobeam cavities due to cross-coupling opto-mechanical mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Daniel, E-mail: daniel.ramos@csic.es; Frank, Ian W.; Deotare, Parag B.; Bulu, Irfan; Lončar, Marko [School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2014-11-03

    We investigate the coupling between mechanical and optical modes supported by coupled, freestanding, photonic crystal nanobeam cavities. We show that localized cavity modes for a given gap between the nanobeams provide weak optomechanical coupling with out-of-plane mechanical modes. However, we show that the coupling can be significantly increased, more than an order of magnitude for the symmetric mechanical mode, due to optical resonances that arise from the interaction of the localized cavity modes with standing waves formed by the reflection from thesubstrate. Finally, amplification of motion for the symmetric mode has been observed and attributed to the strong optomechanical interaction of our hybrid system. The amplitude of these self-sustained oscillations is large enough to put the system into a non-linear oscillation regime where a mixing between the mechanical modes is experimentally observed and theoretically explained.

  18. Observation of nonlinear bands in near-field scanning optical microscopy of a photonic-crystal waveguide

    CERN Document Server

    Singh, Amandev; Huisman, Simon R; Korterik, Jeroen P; Mosk, Allard P; Herek, Jennifer L; Pinkse, Pepijn W H

    2014-01-01

    We have measured the photonic bandstructure of GaAs photonic-crystal waveguides with high energy and momentum resolution using near-field scanning optical microscopy. Intriguingly, we observe additional bands that are not predicted by eigenmode solvers, as was recently demonstrated by Huisman et al. [Phys. Rev. B 86, 155154 (2012)]. We study the presence of these additional bands by performing measurements of these bands while varying the incident light power, revealing a non-linear power dependence. Here, we demonstrate experimentally and theoretically that the observed additional bands are caused by a waveguide-specific near- field tip effect not previously reported, which can significantly phase-modulate the detected field.

  19. Studies on spatial modes and the correlation anisotropy of entangled photons generated from 2D quadratic nonlinear photonic crystals

    Science.gov (United States)

    Luo, X. W.; Xu, P.; Sun, C. W.; Jin, H.; Hou, R. J.; Leng, H. Y.; Zhu, S. N.

    2017-06-01

    Concurrent spontaneous parametric down-conversion (SPDC) processes have proved to be an appealing approach for engineering the path-entangled photonic state with designable and tunable spatial modes. In this work, we propose a general scheme to construct high-dimensional path entanglement and demonstrate the basic properties of concurrent SPDC processes from domain-engineered quadratic nonlinear photonic crystals, including the spatial modes and the photon flux, as well as the anisotropy of spatial correlation under noncollinear quasi-phase-matching geometry. The overall understanding about the performance of concurrent SPDC processes will give valuable references to the construction of compact path entanglement and the development of new types of photonic quantum technologies.

  20. Mid-IR femtosecond frequency conversion by soliton-probe collision in phase-mismatched quadratic nonlinear crystals

    CERN Document Server

    Liu, Xing; Guo, Hairun; Bache, Morten

    2015-01-01

    We show numerically that ultrashort self-defocusing temporal solitons colliding with a weak pulsed probe in the near-IR can convert the probe to the mid-IR. A near-perfect conversion efficiency is possible for a high effective soliton order. The near-IR self-defocusing soliton can form in a quadratic nonlinear crystal (beta-barium borate) in the normal dispersion regime due to cascaded (phase-mismatched) second-harmonic generation, and the mid-IR converted wave is formed in the anomalous dispersion regime between $\\lambda=2.2-2.4~\\mu\\rm m$ as a resonant dispersive wave. This process relies on non-degenerate four-wave mixing mediated by an effective negative cross-phase modulation term caused by cascaded soliton-probe sum-frequency generation.

  1. Molecular Optics Nonlinear Optical Processes in Organic and Polymeric Crystals and Films. Part 2

    Science.gov (United States)

    1991-11-01

    susceptibility gamma ijkl(-omega 4; omega 1, omega 2, omega 3 ) demonstrate that the microscopic origin of the nonresonant third order nonlinear optical...interaction calculations of gamma jkl(-omega 4; omega 1, omega 2, omega 3 ) for the archetypal class of quasi-one dimensional conjugated structures...largest of the two dominant, competing virtual excitation processes that determine gamma ijkl(- omega 4; omega 1, omega 2, omega 3 ). It is also found in

  2. The effect of 100 MeV oxygen ion on electrical and optical properties of nonlinear optical l-alanine sodium nitrate single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ahlam, M. A.; Prakash, A. P. Gnana [Department of Studies in Physics, University of Mysore, Mysore-570 006, Karnataka (India)

    2012-06-05

    Single crystals of nonlinear optical (NLO) L-alanine Sodium Nitrate (LASN) were grown by slow evaporation method. The grown crystals were irradiated by 100 MeV oxygen ions with the cumulative doses of 1Mrad, 6 Mrad and 10 Mrad. The dielectric properties, differential scanning calorimetry (DSC) and second harmonic generation (SHG) of the crystals were studied before and after irradiation. The dielectric constant was found to increase after irradiation. The DSC reveals that the melting point remains unaffected due to irradiation. The SHG efficiency of LASN was found to decrease with increase in radiation dose.

  3. The effect of 100 MeV oxygen ion on electrical and optical properties of nonlinear optical l-alanine sodium nitrate single crystals

    Science.gov (United States)

    Ahlam, M. A.; Prakash, A. P. Gnana

    2012-06-01

    Single crystals of nonlinear optical (NLO) L-alanine Sodium Nitrate (LASN) were grown by slow evaporation method. The grown crystals were irradiated by 100 MeV oxygen ions with the cumulative doses of 1Mrad, 6 Mrad and 10 Mrad. The dielectric properties, differential scanning calorimetry (DSC) and second harmonic generation (SHG) of the crystals were studied before and after irradiation. The dielectric constant was found to increase after irradiation. The DSC reveals that the melting point remains unaffected due to irradiation. The SHG efficiency of LASN was found to decrease with increase in radiation dose.

  4. Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-chloro 4-nitrostilbene (CONS): a potential NLO material.

    Science.gov (United States)

    Dinakaran, Paul M; Kalainathan, S

    2013-07-01

    4-Chloro 4-nitrostilbene (CONS) a new organic nonlinear optical material has been synthesized. Employing slow evaporation method, good optical quality single crystals (dimensions up to 6×2×3 mm(3)) have been grown using ethyl methyl ketone (EMK) as a solvent. The grown crystals have been subjected to various characterizations such as single crystal X-ray diffraction, powder XRD, Fourier Transform Infrared spectroscopy (FTIR), proton NMR, solid UV absorption, SHG studies. Single crystal X-ray diffraction reveals that the crystal system belongs to monoclinic with noncentrosymmetric space group P21. The UV-Vis absorption spectrum has been recorded and found that the cut off wavelength is 380 nm. Functional groups and the structure of the title compound have been confirmed by FTIR and (1)H NMR spectroscopic analyses respectively. Molecular mass of the CONS confirmed by the high resolution mass spectral analysis .The thermal behavior of the grown crystal has been studied by TG/DTA analysis and it shows the melting point is at 188.66 °C. Dislocations and growth pattern present in the grown crystal revealed by the etching study. The mechanical strength of the CONS crystal has been studied by Vicker's hardness measurement. The SHG efficiency of the grown crystal has been determined by Kurtz and Perry powder test which revealed that the CONS crystal (327 mV) has 15 times greater efficiency than that of KDP (21.7 mV).

  5. Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-chloro 4-nitrostilbene (CONS): A potential NLO material

    Science.gov (United States)

    Dinakaran, Paul M.; Kalainathan, S.

    2013-07-01

    4-Chloro 4-nitrostilbene (CONS) a new organic nonlinear optical material has been synthesized. Employing slow evaporation method, good optical quality single crystals (dimensions up to 6 × 2 × 3 mm3) have been grown using ethyl methyl ketone (EMK) as a solvent. The grown crystals have been subjected to various characterizations such as single crystal X-ray diffraction, powder XRD, Fourier Transform Infrared spectroscopy (FTIR), proton NMR, solid UV absorption, SHG studies. Single crystal X-ray diffraction reveals that the crystal system belongs to monoclinic with noncentrosymmetric space group P21. The UV-Vis absorption spectrum has been recorded and found that the cut off wavelength is 380 nm. Functional groups and the structure of the title compound have been confirmed by FTIR and 1H NMR spectroscopic analyses respectively. Molecular mass of the CONS confirmed by the high resolution mass spectral analysis .The thermal behavior of the grown crystal has been studied by TG/DTA analysis and it shows the melting point is at 188.66 °C. Dislocations and growth pattern present in the grown crystal revealed by the etching study. The mechanical strength of the CONS crystal has been studied by Vicker's hardness measurement. The SHG efficiency of the grown crystal has been determined by Kurtz and Perry powder test which revealed that the CONS crystal (327 mV) has 15 times greater efficiency than that of KDP (21.7 mV).

  6. 5.5 W of Diffraction-Limited Green Light Generated by SFG of Tapered Diode Lasers in a Cascade of Nonlinear Crystals

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Jensen, Ole Bjarlin; Andersen, Peter Eskil

    2015-01-01

    Diode-based high power visible lasers are perfect pump sources for, e.g., titaniumsapphire lasers. The combination of favorable scaling laws in both SFG and cascading of nonlinear crystals allows access to unprecedented powers in diode-based systems....

  7. All-optical wavelength multicasting with extinction ratio enhancement using pump-modulated four-wave mixing in a dispersion-flattened nonlinear photonic crystal fiber

    DEFF Research Database (Denmark)

    Chow, K.K.; Shu, Chester; Lin, Chinlon;

    2006-01-01

    All optical wavelength multicasting at 4 x 10 Gb/s with extinction ratio enhancement has been demonstrated based on pump-modulated four-wave mixing in a nonlinear photonic crystal fiber. We show that the input signal wavelength can simultaneously convert to four different wavelengths, with a power...

  8. Heterodyne pump probe measurements of nonlinear dynamics in an indium phosphide photonic crystal cavity

    DEFF Research Database (Denmark)

    Heuck, Mikkel; Combrié, S.; Lehoucq, G.

    2013-01-01

    Using a sensitive two-color heterodyne pump-probe technique, we investigate the carrier dynamics of an InP photonic crystal nanocavity. The heterodyne technique provides unambiguous results for all wavelength configurations, including the degenerate case, which cannot be investigated with the wid...... with the widely used homodyne technique. A model based on coupled mode theory including two carrier distributions is introduced to account for the relaxation dynamics, which is assumed to be governed by both diffusion and recombination.......Using a sensitive two-color heterodyne pump-probe technique, we investigate the carrier dynamics of an InP photonic crystal nanocavity. The heterodyne technique provides unambiguous results for all wavelength configurations, including the degenerate case, which cannot be investigated...

  9. Photoinduced nonlinear optical effects in Nd-doped δ-BiB{sub 3}O{sub 6} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Majchrowski, A. [Institute of Applied Physics, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Wojciechowski, A. [Faculty of Electrical Engineering, Czestochowa University Technology, Armii Krajowej 17 (Poland); Kityk, I.V., E-mail: ikityk@el.pcz.czest.pl [Faculty of Electrical Engineering, Czestochowa University Technology, Armii Krajowej 17 (Poland); Chrunik, M.; Jaroszewicz, L.R. [Institute of Applied Physics, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Michalski, E. [Institute of Optoelectronics, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland)

    2014-10-15

    Highlights: • New type of optically operated rare earth doped borates is proposed. • Principal role of the phonon subsystem in photoinduced electrooptics, SHG and piezooptics is shown. • The possibility to create the laser operated materials is shown for the such kind of sold state alloys. - Abstract: The studies of the second harmonic generation, Pockels effect and piezoelectricity were performed for the new synthesized δ-BiB{sub 3}O{sub 6} single crystals. The incorporation of Nd{sup 3+} ions into these crystals plays an important role for the increasing of the photoinduced nonlinear optical properties. Temperature dependences of the optical and piezoelectric features showed existence of some anomalies in the vicinity of 160 K and 220 K. This may confirm a principal role of the photopolarization and of the localized impurity states which give additional contribution into the observed effect. It is crucial that the effect is dependent on the number of the photoinducing pulses. The effect is completely reversible after switching off of the photoinducing laser beam.

  10. Generation and propagation of high-order Bessel vortices in linear and non-linear crystals

    CSIR Research Space (South Africa)

    Belyi, VN

    2009-08-01

    Full Text Available E⊥ of the electric field for these beams are given by the following expressions: ( ))2exp()()( )( )exp( 20 1 10 ϕρρ iqJqJ qw zikA i zoo −+⊥ += eeE , (1) с Uniaxial crystal θs Bs2ω(ρ) Bsω(ρ) Figure 1: Geometry of SHG when wave vectors cone of Bessel...

  11. Hybrid liquid crystals: Enhanced electro-optic and nonlinear response for manipulating beams (Conference Presentation)

    Science.gov (United States)

    Kaczmarek, Malgosia; D'Alessandro, Giampaolo; Proctor, Matthew B.

    2016-09-01

    The manipulation and processing of light beams can be efficiently accomplished through devices based on soft matter placed in a hybrid "symbiosis" with other organic or inorganic, photoresponsive materials. The performance of such smart modulating systems often relies on a subtle balance between individual properties of each component, together with the varying interaction between organic and inorganic elements. Some promising demonstrations in the visible as well as in the THz regimes include liquid crystals integrated with plasmonic or ferroelectric nanoparticles, photoconductive or photosensitive polymers as well as metamaterials. They offer adaptive, flexible and tailor-made solutions for applications in displays and optoelectronics, switching, steering and modulating electromagnetic waves. Hybrid configurations that include multiple photoresponsive layers, sandwiched with liquid crystals, led to stronger modulation and steering of light beams in the visible. Such effects can also be observed in the other regions of spectrum, as inorganic nanoparticles dispersed in liquid crystals modify the magnitude of the material refractive indices measured in THz. The development of such hybrid materials has to be accompanied by comprehensive characterisation of their uniformity, stability and optical quality across the whole surface of the device, capable of determining their optical, electrical and physical parameters.

  12. Nonlinear Response of One-Dimensional Magneto-Optical Photonic Crystals

    Institute of Scientific and Technical Information of China (English)

    WANG Wei-Zhong

    2005-01-01

    @@ We numerically investigate the magneto-optical Cotton-Mouton effect in an alternating multilayer structure with a nonlinear dielectric constant. The multistability and polarization of the transmission of electromagnetic field near the edges of the stop gap are studied in detail. The resonant transmission is accompanied by solitons of intensity of the field. This investigation provides a way to select the transmission property with different polarizations since both the amplitude and the phase of the output field can be adjusted by the input power and by the magneto-optical coefficient depending on the external magnetic field.

  13. Non-centrosymmetric crystals of new N-benzylideneaniline derivatives as potential materials for non-linear optics.

    Science.gov (United States)

    Souza, Talita Evelyn; Rosa, Iara Maria Landre; Legendre, Alexandre Oliveira; Paschoal, Diego; Maia, Lauro J Q; Dos Santos, Hélio F; Matins, Felipe Terra; Doriguetto, Antonio Carlos

    2015-08-01

    Three new N-benzylideneaniline derivatives [p-nitrobenzylidene-p-phenylamineaniline (I), 2,4-dinitrobenzylidene-p-phenylamineaniline (II) and p-dinitrobenzylidene-p-diethylamineaniline (III)] containing electron-push-pull groups have been prepared. They present a planar N-benzylideneaniline core and neighbouring functional atoms, which are related through an efficient intramolecular charge transfer (CT). Two of the derivatives crystallize in non-centrosymmetric space groups, a necessary condition for non-linear optical (NLO) responses. The NLO properties were calculated for the molecular conformations determined by single-crystal X-ray diffraction as well as for the four molecules packed into each corresponding unit cell, using a quantum-chemical method at the cam-B3LYP/NLO-V level of theory. As expected from antiparallel face-to-face stacking through centrosymmetry, the main NLO descriptors - namely, the first hyperpolarizability (βtot) and its projection on the dipole moment direction (βvec) - are almost zero for the tetramer of derivative III. Interestingly, the calculated first hyperpolarizability decreases in the non-centrosymmetric unit-cell content of derivative II when compared to its single molecule, which may be related to its molecular pillaring, similar to that observed in derivative III. On the other hand, a desirable magnification of the NLO properties was found for packed units of derivative I, which may be a consequence of its parallel face-to-tail stacking with the CT vectors of all molecules pointing in the same direction. Moreover, the CT vector of compound I makes an angle of θ = 33.6° with its crystal polar axis, resulting in a higher-order parameter (cos(3)θ = 0.6) compared with the other derivatives. This is in line with the higher macroscopic second-order NLO response predicted for derivative I, βtot = 120.4 × 10(-30) e.s.u.

  14. Multifunctional Bi{sub 2}ZnOB{sub 2}O{sub 6} single crystals for second and third order nonlinear optical applications

    Energy Technology Data Exchange (ETDEWEB)

    Iliopoulos, K. [LUNAM Université, Université d' Angers, CNRS UMR 6200, Laboratoire MOLTECH-Anjou, 2 Bd Lavoisier, 49045 Angers Cedex (France); Institute of Chemical Engineering Sciences, Foundation for Research and Technology Hellas (FORTH/ICE-HT), 26504 Patras (Greece); Kasprowicz, D. [Faculty of Technical Physics, Poznan University of Technology, Nieszawska 13 A, 60-965 Poznan (Poland); Majchrowski, A. [Institute of Applied Physics, Military University of Technology, Kaliskiego 2, 00-908 Warszawa (Poland); Michalski, E. [Institute of Optoelectronics, Military University of Technology, Kaliskiego 2, 00-908 Warszawa (Poland); Gindre, D.; Sahraoui, B., E-mail: bouchta.sahraoui@univ-angers.fr [LUNAM Université, Université d' Angers, CNRS UMR 6200, Laboratoire MOLTECH-Anjou, 2 Bd Lavoisier, 49045 Angers Cedex (France)

    2013-12-02

    Bi{sub 2}ZnOB{sub 2}O{sub 6} nonlinear optical single crystals were grown by means of the Kyropoulos method from stoichiometric melt. The second and third harmonic generation (SHG/THG) of Bi{sub 2}ZnOB{sub 2}O{sub 6} crystals were investigated by the SHG/THG Maker fringes technique. Moreover, SHG microscopy studies were carried out providing two-dimensional SHG images as a function of the incident laser polarization. The high nonlinear optical efficiency combined with the possibility to grow high quality crystals make Bi{sub 2}ZnOB{sub 2}O{sub 6} an excellent candidate for photonic applications.

  15. Energetic mid-IR femtosecond pulse generation by self-defocusing soliton-induced dispersive waves in a bulk quadratic nonlinear crystal

    DEFF Research Database (Denmark)

    Zhou, Binbin; Guo, Hairun; Bache, Morten

    2015-01-01

    and without critical phase-matching requirements. Pumping a bulk quadratic nonlinear crystal (unpoled LiNbO3 cut for noncritical phase-mismatched interaction) with sub-mJ near-IR 50-fs pulses, tunable and broadband (∼ 1,000 cm−1) mid-IR pulses around 3.0 μm are generated with excellent spatio-temporal pulse...... quality, having up to 10.5 μJ energy (6.3% conversion). The mid-IR pulses are dispersive waves phase-matched to near-IR self-defocusing solitons created by the induced self-defocusing cascaded nonlinearity. This process is filament-free and the input pulse energy can therefore be scaled arbitrarily...... by using large-aperture crystals. The technique can readily be implemented with other crystals and laser wavelengths, and can therefore potentially replace current ultrafast frequency-conversion processes to the mid-IR....

  16. An investigation of doubly-resonant optical parametric oscillators and nonlinear crystals for squeezing

    Energy Technology Data Exchange (ETDEWEB)

    Stefszky, Michael; Buchler, Ben C; Symul, Thomas; Lam, Ping Koy [Quantum Optics Group, Department of Quantum Science, The Australian National University, ACT 0200 (Australia); Mow-Lowry, Conor M; McKenzie, Kirk; Chua, Sheon; McClelland, David E, E-mail: michael.stefszky@anu.edu.au [Centre for Gravitational Physics, Department of Quantum Science, The Australian National University, ACT 0200 (Australia)

    2011-01-14

    A squeezed light source requires properties such as high squeezing amplitude, high bandwidth and stability over time, ideally using as few resources, such as laser power, as possible. We compare three nonlinear materials, two of which have not been well characterized for squeezed state production, and also investigate the viability of doubly-resonant optical parametric oscillator cavities in achieving these requirements. A model is produced that provides a new way of looking at the construction of an optical parametric oscillator/optical parametric amplifier setup where second harmonic power is treated as a limited resource. The well-characterized periodically poled potassium titanyl phosphate (PPKTP) is compared in an essentially identical setup to two relatively new materials, periodically poled stoichiometric lithium tantalate (PPSLT) and 1.7% magnesium oxide doped periodically poled stoichiometric lithium niobate (PPSLN). Although from the literature PPSLT and PPSLN present advantages such as a higher damage threshold and a higher nonlinearity, respectively, PPKTP was still found to have the most desirable properties. With PPKTP, 5.8 dB of squeezing below the shot noise limit was achieved. With PPSLT, 5.0 dB of squeezing was observed but the power required to see this squeezing was much higher than expected. A technical problem with the PPSLN limited the observed squeezing to around 1.0 dB. This problem is discussed.

  17. Pitchfork Bifurcation and Zharov Splitting in Nonlinear Mid-infrared Photothermal Spectroscopy in a liquid crystal using a Quantum Cascade Laser

    CERN Document Server

    Mertiri, Alket; Hong, M K; Mehta, P; Mertz, J; Ziegler, L D; Erramilli, Shyamsunder

    2013-01-01

    We report on the mid-infrared nonlinear photothermal spectrum of the neat liquid crystal 4-Octyl-4'-Cyanobiphenyl (8CB) using a tunable Quantum Cascade Laser (QCL). The nonequilibrium steady state characterized by the nonlinear photothermal infrared response undergoes a supercritical pitchfork bifurcation. The bifurcation, observed in heterodyne two-color pump-probe detection, leads to ultrasharp nonlinear infrared spectra similar to those reported in the visible region. A systematic study of the peak splitting as function of absorbed infrared power shows the bifurcation has a critical exponent of 0.5. The surprising observation of an apparently universal critical exponent in a nonequilibrium state is explained using a simple model reminiscent of mean field theory. Apart from the intrinsic interest for nonequilibrium studies, nonlinear photothermal methods lead to a dramatic narrowing of spectral lines, giving rise to a potential new contrast mechanism for the rapidly emerging new field of mid-infrared micros...

  18. Extending of flat normal dispersion profile in all-solid soft glass nonlinear photonic crystal fibres

    Science.gov (United States)

    Siwicki, Bartłomiej; Kasztelanic, Rafał; Klimczak, Mariusz; Cimek, Jarosław; Pysz, Dariusz; Stępień, Ryszard; Buczyński, Ryszard

    2016-06-01

    The bandwidth of coherent supercontinuum generated in optical fibres is strongly determined by the all-normal dispersion characteristic of the fibre. We investigate all-normal dispersion limitations in all-solid oxide-based soft glass photonic crystal fibres with various relative inclusion sizes and lattice constants. The influence of material dispersion on fibre dispersion characteristics for a selected pair of glasses is also examined. A relation between the material dispersion of the glasses and the fibre dispersion has been described. We determined the parameters which limit the maximum range of flattened all-normal dispersion profile achievable for the considered pair of heavy-metal-oxide soft glasses.

  19. Investigation of thermal evolution of nanodomain structures in nonlinear barium sodium niobate crystals

    Institute of Scientific and Technical Information of China (English)

    S.V.Ivanova

    2008-01-01

    By the 90°elastic light scattering investigation and far field observation in the range of 20-800℃,the relation between behavior of light scattering anomalies and evolution of nanodomain structures in lattice of barium sodium niobate(Ba2NaNb5O15,BSN)crystal was clarified.The correlation between anomalies on the temperature curves of the elastic light scattering intensity and temperature transformations of nanodomains was studied by X-ray and electron microscope methods.Phase transition near 500℃ and movement in field of scattering light could be explained by appearance of a new incommensurate phase.

  20. Development of Multifunctional Ultra-Nonlinear Liquids and Liquid Crystals for Sensor Protection Applications

    Science.gov (United States)

    2008-03-01

    10. SPONSOR/MONITOR’S ACRONYM(S) Air Force Office of Scientific Research AFOSR/NA 875 Randolph Street Suite 325, Room 3112 11. SPONSORIMONITOR’S...optical meta-materials," Invited paper, 12 th Int. Topical Meeting on Optics of Liquid Crystals," Puebla , Mexico, Oct. 1-5, 2007. *21. I. C. Khoo and A...DOD Laboratories and Development Centers (i) Wright Patterson Air Force Base [Tim Bunning, Paul Fleitz, Joy Rogers and Augustine Urbus]: We have

  1. Recent advances in very highly nonlinear chalcogenide photonic crystal fibers and their applications

    Science.gov (United States)

    Méchin, David; Brilland, Laurent; Troles, Johann; Chartier, Thierry; Besnard, Pascal; Canat, Guillaume; Renversez, Gilles

    2012-02-01

    Perfos and the laboratory Glasses and Ceramics Group of University of Rennes 1 have worked together to develop a new fabrication technique for chalcogenide preforms based on the glass-casting process. Various fiber profiles have been designed by the Fresnel Institute and fiber losses have been significantly improved, approaching those of the material losses. Using this technology, we have manufactured an AsSe CPCF exhibiting a nonlinear coefficient γ of 46 000 W-1km-1. Self-phase modulation, Raman effect, Brillouin effect, Four-Wave Mixing have been observed leading to the demonstration of various optical functions such four-wave mixing based wavelength conversion at 1.55 μm by FOTON, the demonstration of Raman Shifts and the generation of a mid-IR supercontinuum source by ONERA and the demonstration of a Brillouin fiber laser by FOTON.

  2. Synthesis, growth and characterization of organic nonlinear optical single crystal 1,3-bis(4-methoxyphenyl)prop-2-en-1-one (BMP) by vertical Bridgman technique

    Science.gov (United States)

    Arunkumar, K.; Kalainathan, S.

    2017-03-01

    An organic nonlinear optical (NLO) material 1,3-bis(4-methoxyphenyl)prop-2-en-1-one (BMP) single crystal has been successfully grown by vertical Bridgman stockbarger technique (VBT) using single wall ampoule. The grown crystal was subjected to single-crystal X-ray diffraction analysis (SXRD) to confirm the cell parameters and powder X-ray diffraction analysis (PXRD) to confirm the crystallinity. FTIR analyses were carried to identify the functional groups. The UV-Vis spectrum of BMP showed the lower optical cut off at 435 nm and is transparent in the visible region. The mechanical property of the titled crystal is analyzed by using microhardness measurements. Laser damage threshold energy was determined using Nd: YAG laser (1064 nm). The photoconductivity study of BMP reveals the positive photoconducting nature. The NLO property of the grown crystal confirmed by Kurtz and Perry powder technique and the SHG efficiency of the grown crystal was obtained to be 1.04 times greater than Urea. Z-scan studies calculated the third order nonlinear optical parameters like refractive index (n2), the absorption coefficient (β) and third order susceptibility (χ3).

  3. Structural recovery in plastic crystals by time-resolved non-linear dielectric spectroscopy.

    Science.gov (United States)

    Riechers, Birte; Samwer, Konrad; Richert, Ranko

    2015-04-21

    The dielectric relaxation of several different plastic crystals has been examined at high amplitudes of the ac electric fields, with the aim of exploring possible differences with respect to supercooled liquids. In all cases, the steady state high field loss spectrum appears to be widened, compared with its low field limit counterpart, whereas peak position and peak amplitude remain almost unchanged. This field induced change in the loss profile is explained on the basis of two distinct effects: an increased relaxation time due to reduced configurational entropy at high fields which affects the low frequency part of the spectrum, and accelerated dynamics at frequencies above the loss peak position resulting from the added energy that the sample absorbs from the external electric field. From the time-resolved assessment of the field induced changes in fictive temperatures at relatively high frequencies, we find that this structural recovery is slaved to the average rather than mode specific structural relaxation time. In other words, the very fast relaxation modes in the plastic crystal cannot adjust their fictive temperatures faster than the slower modes, the equivalent of time aging-time superposition. As a result, an explanation for this single fictive temperature must be consistent with positional order, i.e., translational motion or local density fluctuations do not govern the persistence time of local time constants.

  4. From polymer to monomer: cleavage and rearrangement of Si-O-Si bonds after oxidation yielded an ordered cyclic crystallized structure.

    Science.gov (United States)

    Zuo, Yujing; Gou, Zhiming; Cao, Jinfeng; Yang, Zhou; Lu, Haifeng; Feng, Shengyu

    2015-07-27

    Polymerization reactions are very common in the chemical industry, however, the reaction in which monomers are obtained from polymers is rarely invesitgated. This work reveals for the first time that oxone can break the Si-O-Si bond and induce further rearrangement to yield an ordered cyclic structure. The oxidation of P1, which is obtained by reaction of 2,2'-1,2-ethanediylbis(oxy)bis(ethanethiol) (DBOET) with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane (MM(Vi)), with oxone yielded cyclic crystallized sulfone-siloxane dimer (P1-ox) after unexpected cleavage and rearrangement of the Si-O-Si bond.

  5. Determination of the Dalitz plot parameter {alpha} for the decay {eta}{yields}3{pi}{sup 0} with the Crystal Ball at MAMI-B

    Energy Technology Data Exchange (ETDEWEB)

    Unverzagt, M.; Beck, R.; Lang, M.; Nikolaev, A.; Schumann, S. [University Mainz, Institut fuer Kernphysik, Mainz (Germany); University Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany); Aguar-Bartolome, P.; Ahrens, J.; Arends, H.J.; Heid, E.; Jahn, O.; Krambrich, D.; Martinez-Fabregate, M.; Rost, M.; Thomas, A.; Walcher, T. [University Mainz, Institut fuer Kernphysik, Mainz (Germany); Annand, J.R.M.; Codling, R.; Livingston, K.; MacGregor, I.J.D.; McGeorge, J.C.; Owens, R.O.; Rosner, G. [University of Glasgow, Department of Physics and Astronomy, Glasgow (United Kingdom); Bekrenev, V. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Boillat, B.; Krusche, B.; Zehr, F. [University Basel, Institut fuer Physik, Basel (Switzerland); Braghieri, A.; Pedroni, P.; Rostomyan, T. [INFN Sezione di Pavia, Pavia (Italy); Branford, D.; Glazier, D.I.; Tarbert, C.M.; Watts, D.P. [Univ. of Edinburgh, School of Physics, Edinburgh (United Kingdom); Briscoe, W.J. [The George Washington Univ., Center for Nuclear Studies, Washington, D.C. (United States); Brudvik, J.W.; Nefkens, B.M.K.; Prakhov, S.N.; Price, J.W.; Starostin, A. [Univ. of California at Los Angeles, Los Angeles, CA (United States); Cherepnya, S.; Fil' kov, L.V.; Kashevarov, V.L. [Lebedev Physical Inst., Moscow (Russian Federation); Downie, E.J. [Univ. Mainz, Inst. fuer Kernphysik, Mainz (Germany); Univ. of Glasgow, Dept. of Physics and Astronomy, Glasgow (United Kingdom); Gregor, R.; Kotulla, M.; Lugert, S.; Metag, V.; Novotny, R. [Univ. Giessen, II. Physikalisches Inst., Giessen (Germany); Hornidge, D. [Mount Allison Univ., Sackville, NB (Canada); Kondratiev, R.; Lisin, V.; Polonski, A. [Institute for Nuclear Research, Moscow (Russian Federation); Korolija, M.; Mekterovic, D.; Supek, I. [Rudjer Boskovic Inst., Zagreb (Croatia); Manley, D.M. [Kent State Univ., Kent, OH (United States); Sober, D. [The Catholic Univ. of America, Washington, D.C. (United States)

    2009-02-15

    A precise measurement of the Dalitz plot parameter, {alpha}, for the {eta}{yields}3{pi}{sup 0} decay is presented. The experiment was performed with the Crystal Ball and TAPS large-acceptance photon detectors at the tagged photon beam facility of the MAMI-B electron accelerator in Mainz. High statistics of 1.8.10{sup 6} {eta}{yields}3{pi}{sup 0} events were obtained, giving the result {alpha}=-0.032{+-}0.002{sub stat}{+-}0.002{sub syst}. (orig.)

  6. A force-level theory of the rheology of entangled rod and chain polymer liquids. I. Tube deformation, microscopic yielding, and the nonlinear elastic limit

    Science.gov (United States)

    Schweizer, Kenneth S.; Sussman, Daniel M.

    2016-12-01

    We employ a first-principles-based, force-level approach to construct the anharmonic tube confinement field for entangled fluids of rigid needles, and also for chains described at the primitive-path (PP) level in two limiting situations where chain stretch is assumed to either be completely equilibrated or unrelaxed. The influence of shear and extensional deformation and polymer orientation is determined in a nonlinear elastic limit where dissipative relaxation processes are intentionally neglected. For needles and PP-level chains, a self-consistent analysis of transverse polymer harmonic dynamical fluctuations predicts that deformation-induced orientation leads to tube weakening or widening. In contrast, for deformed polymers in which chain stretch does not relax, we find tube strengthening or compression. For all three systems, a finite maximum transverse entanglement force localizing the polymers in effective tubes is predicted. The conditions when this entanglement force can be overcome by an externally applied force associated with macroscopic deformation can be crisply defined in the nonlinear elastic limit, and the possibility of a "microscopic absolute yielding" event destroying the tube confinement can be analyzed. For needles and contour-relaxed PP chains, this force imbalance occurs at a stress of order the equilibrium shear modulus and a strain of order unity, corresponding to a mechanically fragile entanglement tube field. However, for unrelaxed stretched chains, tube compression stabilizes transverse polymer confinement, and there appears to be no force imbalance. These results collectively suggest that the crossover from elastic to irreversible viscous response requires chain retraction to initiate disentanglement. We qualitatively discuss comparisons with existing phenomenological models for nonlinear startup shear, step strain, and creep rheology experiments.

  7. Studies on the synthesis, spectral, optical and thermal properties of l-Valine Zinc Sulphate: an organic inorganic hybrid nonlinear optical crystal.

    Science.gov (United States)

    Puhal Raj, A; Ramachandra Raja, C

    2012-11-01

    Nonlinear optical (NLO) organic inorganic hybrid l-Valine Zinc Sulphate (LVZS) was synthesized and single crystals were obtained from saturated aqueous solution by slow evaporation method at 36°C using a constant temperature bath (CTB) with an accuracy of ±0.01°C. This crystal is reported with its characterization by single crystal and powder XRD, FTIR, UV-Vis-NIR, TG/DTA analysis and SHG test. Single crystal XRD study reveals that LVZS crystallizes in monoclinic system with the lattice constants a=9.969(3) Å, b=7.238(3) Å, c=24.334(9) Å and cell volume is 1736.00Å(3). Sharp peaks observed in powder X-ray diffraction studies confirm the high degree of crystallinity of grown crystal. The incorporation of sulphate ion with l-valine is confirmed by FTIR spectrum in LVZS crystal(.) A remarkable increase in optical transparency has been observed in LVZS when compared to l-valine and zinc sulphate heptahydrate Thermal properties of LVZS have been reported by using TG/DTA analysis. Kurtz powder second harmonic generation (SHG) test confirms NLO property of the crystal and SHG efficiency of LVZS was found to be 1.34 times more than pure l-valine.

  8. Studies on the synthesis, spectral, optical and thermal properties of L-Valine Zinc Sulphate: An organic inorganic hybrid nonlinear optical crystal

    Science.gov (United States)

    Puhal Raj, A.; Ramachandra Raja, C.

    2012-11-01

    Nonlinear optical (NLO) organic inorganic hybrid L-Valine Zinc Sulphate (LVZS) was synthesized and single crystals were obtained from saturated aqueous solution by slow evaporation method at 36 °C using a constant temperature bath (CTB) with an accuracy of ±0.01 °C. This crystal is reported with its characterization by single crystal and powder XRD, FTIR, UV-Vis-NIR, TG/DTA analysis and SHG test. Single crystal XRD study reveals that LVZS crystallizes in monoclinic system with the lattice constants a = 9.969(3) Å, b = 7.238(3) Å, c = 24.334(9) Å and cell volume is 1736.00 Å3. Sharp peaks observed in powder X-ray diffraction studies confirm the high degree of crystallinity of grown crystal. The incorporation of sulphate ion with L-valine is confirmed by FTIR spectrum in LVZS crystal. A remarkable increase in optical transparency has been observed in LVZS when compared to L-valine and zinc sulphate heptahydrate Thermal properties of LVZS have been reported by using TG/DTA analysis. Kurtz powder second harmonic generation (SHG) test confirms NLO property of the crystal and SHG efficiency of LVZS was found to be 1.34 times more than pure L-valine.

  9. Self-assembly synthesis,crystal structure and nonlinear optical properties of cluster compound containing PPh2Py ligand

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jian-liang; WEI Chuan-jun; TONG Hai-xia; CHUN Xiao-gai; CHEN Qi-yuan

    2008-01-01

    Self-assembly cluster compound [WS4Cu3(PPh2Py)3Br]2·CH3OH (1) was synthesized by the reaction of (NH4)2WS4,CuBr and diphenyl-2-pyridyl-phosphine (PPh2Py) in CH3OH solution under a purified nitrogen atmosphere using standard Schlenk techniques.Its structure was determined by X-ray crystallography.It crystallizes in the triclinic crystal system P-1 space group with α=1.178 6(1)nm,b=1.302 6(1)nm,c=1.9917(2)nm,α=74.671(7)°,β=86.188(8)°,γ=64.141(6)°,V=2.649 5(5)nm',Z=1.The W center is slightly distorted from tetrahedral coordination geometry,and the structure is built up from three [Cu(PPh2Py)]+ units bridged by WS2-4 multifunctional ligand to form a tetranuclear symmetrical cube-like molecule.Measurement of the nonlinear optical (NLO) properties using the Z-scan technique with an 8 ns pulsed laser at 532 nm shows that the compound possesses NLO absorption and effective self-focusing effect at α2=6.7×10-11m/W and n2=5.64×10-18m2/W in a 1.5×10-4mol/L DMF solution.

  10. Non-linear effects in hopping conduction of single-crystal La2CuO4 + δ

    Science.gov (United States)

    Belevtsev, B. I.; Dalakova, N. V.; Panfilov, A. S.

    1998-11-01

    The unusual non-linear effects in hopping conduction of single-crystal La2CuO4+δ with excess oxygen has been observed. The resistance is measured as a function of the applied voltage U (voltage controlled regime) in the temperature range 5 K⩽T⩽300 K and voltage range 10-3-25 V. At relatively high voltage (approximately at U>0.1 V) the conduction of sample investigated corresponds well to variable-range hopping (VRH). That is, in the range 0.1 Vconductivity does not depend on U (Ohmic behavior) and the temperature dependence of resistance R(T) follows closely Mott's law of VRH [R∝exp(T0/T)1/4]. In the range of highest applied voltage the conduction has been non-Ohmic: the resistance decreases with increasing U. This non-linear effect is quite expected in the frame of VRH mechanism, since the applied electric field increases the hopping probability. A completely different and unusual conduction behavior is found, however, in the low voltage range (approximately below 0.1 V), where the influence of electric field and (or) electron heating effect on VRH ought to be neglected. Here we have observed strong increase in resistance at increasing U at T⩽20 K, whereas at T>20 K the resistance decreases with increasing U. The magnetoresistance of the sample below 20 K has been positive at low voltage and negative at high voltage. The observed unusual non-Ohmic behavior at low voltage range is attributable to inhomogeneity of the sample, namely, to the enrichment of sample surface with oxygen during the course of the heat treatment of the sample in helium and air atmosphere before measurements. At low enough temperature (below ≈20 K) the surface layer with increased oxygen concentration is presumed to consist of disconnected superconducting regions in a poorly conducting (dielectric) matrix. This allows us to explain the observed unusual non-linear effects in the conduction of sample studied. The results obtained demonstrate that in some cases the measured transport

  11. Third order optical non-linear (Z-scan), birefringence, photoluminescence, mechanical and etching studies on melaminium levulinate monohydrate (MLM) single crystal for optical device applications

    Science.gov (United States)

    Sivakumar, N.; Anbalagan, G.

    2016-10-01

    Z-scan studies on the grown crystal was investigated by diode-pumped Nd; YAG laser. Nonlinear refractive index (n2) and third-order nonlinear optical susceptibility (χ3) values of MLM were found to be -1.0 × 10-8 cm2/W and 1.36 × 10-6 esu respectively. Powder X-ray diffraction analysis depicted that the crystal belongs to monoclinic system with space group P21/c. Birefringence study revealed the optical dispersion behavior of MLM crystal. Linear refractive index on (10-1) plane was measured by prism coupling technique and was estimated to be 1.4705. Hardness study was carried out along three different planes which exhibit hardness anisotropy of 41.11%. Meyer's index values of the grown crystal for the (10-1), (010) and (111) planes were found to be 2.39, 2.61 and 2.04 respectively. Etching studies on the prominent (10-1) growth plane was explained by two dimensional layer growth mechanisms. Photoluminescence study was performed on MLM crystal to explore its efficacy towards optical device fabrications.

  12. Growth, structural, optical, thermal and dielectric properties of a novel semi-organic nonlinear optical crystal: Dichloro-diglycine zinc II

    Directory of Open Access Journals (Sweden)

    B. Uma

    2014-08-01

    Full Text Available Dichloro-diglycine zinc II (DCDGZ II, a semi-organic nonlinear optical material has been synthesized and single crystals were grown from the aqueous solution up to dimensions 20×10×3 mm3. The title compound, DCDGZ II (C4H10Cl2N2O4Zn·H2O crystallizes into monoclinic structure with the space group of C2/c. The unit-cell parameters were found to be a=14.4191(7, b=6.9180(2, c=12.9452(6 Å and Z=4. In the crystal structure, DCDGZ II layer is building up alternatingly with layers of water in which the zinc ions lie on a twofold axis. Theoretical calculations for polarizability, which are useful for device fabrication were made using Clausius–Mosotti equation and Penn analysis and the results were compared. Fourier transform infrared (FTIR spectroscopic studies were performed for the identification of the different functional groups presented in the compound. The UV–vis–NIR absorption spectrum reveals that the lower UV cut-off wavelength is 240 nm. The optical band gap of the crystal was estimated as 2.2 eV. The surface morphology, thermal behaviour, dielectric properties have been studied using SEM, TG/DTA and LCR HITESTER analyzer. The nonlinear optical property of the crystal was also confirmed using Kurtz powder technique.

  13. Synthesis, Crystal Structure and Nonlinear Optical Properties of Nickel(Ⅱ) Complex with Schiff-base Ligand

    Institute of Scientific and Technical Information of China (English)

    XUE Zhao-Ming(薛照明); ZHANG Xuan-Jun(张宣军); TIAN Yu-Peng(田玉鹏); WU Jie-Ying(吴杰颖); JIANG Min-Hua(蒋民华); FUN Hoong Kun

    2003-01-01

    The nickel(Ⅱ) complex with the new ligand of S-benzyl-β-N-[10-ethylphenothiazine-3-methylene]dithiocarbazate(HL) crystallizes in the triclinic system, space group P1-with a = 7.516(1), b = 11.322(1), c = 13.366(1) (A),α= 84.818(1),β= 81.688(1), y= 76.037(1)°, V= 1090.26(3) (A)3, Z = 1, Dc=1.413 g/cm3, F(000) = 482,μ(MoKα)= 0.774 mm-1 (λ= 0.7103(A)),R = 0.0573 and wR =0.1375 for 3357 observed reflections withⅠ≥ 2σ(Ⅰ). The HL has lost a proton from its tautomeric thiol form and acts as a single negatively charged bidentate ligand coordinating to the nickel ion via the mercapto sulfur and β-nitrogen atoms. The geometry around Ni(Ⅱ) is almost square-planar with two equivalent Ni-N and Ni-S bonds. The nonlinear absorption of HL and NiL2 solutions (in DMF) was measured by open-aperture Z-scan technique at the wavelength of 532 nm.

  14. Fabrication of GaN/AlGaN 1D photonic crystals designed for nonlinear optical applications

    CERN Document Server

    Stomeo, T; Tasco, V; Tarantini, I; Campa, A; De Vittorio, M; Passaseo, A; Braccini, M; Larciprete, M C; Sibilia, C; Bovino, F A

    2011-01-01

    In this paper we present a reliable process to fabricate GaN/AlGaN one dimensional photonic crystal (1D-PhC) microcavities with nonlinear optical properties. We used a heterostructure with a GaN layer embedded between two Distributed Bragg Reflectors consisting of AlGaN/GaN multilayers, on sapphire substrate, designed to generate a {\\lambda}= 800 nm frequency down-converted signal (\\chi^(2) effect) from an incident pump signal at {\\lambda}= 400 nm. The heterostructure was epitaxially grown by metal organic chemical vapour deposition (MOCVD) and integrates a properly designed 1D-PhC grating, which amplifies the signal by exploiting the double effect of cavity resonance and non linear GaN enhancement. The integrated 1D-PhC microcavity was fabricate combing a high resolution e-beam writing with a deep etching technique. For the pattern transfer we used ~ 170 nm layer Cr metal etch mask obtained by means of high quality lift-off technique based on the use of bi-layer resist (PMMA/MMA). At the same time, plasma co...

  15. Broadband Asymmetric Conical Emission via Cascaded Second-Order Nonlinear Polarization during the Propagation of Femtosecond Laser Pulses in a BBO Crystal

    Institute of Scientific and Technical Information of China (English)

    WEN Jing; JIANG Hong-Bing; YU Jing; YANG Hong; GONG Qi-Huang

    2011-01-01

    @@ We investigate the propagation of femtosecond laser pulses in a 5-mm-thick BBO crystal along the direction of type-Ⅰ phase-matched second-harmonic generation.An intensity-asymmetric broadband conical emission (500- 2000 nm) is demonstrated when a suitable chirp is introduced.It is generated by optical parametric amplification pumped by the second-harmonic light and seeded by the fundamental light which is broadened by cascaded nonlinear processes during second-harmonic generation.

  16. Nonlinear Localization due to a Double Negative Defect Layer in a One-Dimensional Photonic Crystal Containing Single Negative Material Layers

    Institute of Scientific and Technical Information of China (English)

    Munazza Zulfiqar Ali; Tariq Abdullah

    2008-01-01

    We investigate the effects of introducing a defect layer in a one-dimensional photonic crystal containing single negative material layers on the transmission properties.The width of the defect layer js taken to be the same or smaller than the period of the structure.Different cases of the defect layer being linear or nonlinear and double positive or double negative are discussed.It is found that only a nonlinear double negative layer givas rises to a localized mode within the zero-φeff gap in this kind of structure.It is also shown that the important characteristics of the nonlinear defect mode such as its frequency,its FWHM and the threshold of the associated bistability can be controlled by changing the widths of the defect layer and the host layers.

  17. Enormous enhancements of the Kerr nonlinearity at C-band telecommunication wavelength in an Er{sup 3+}-doped YAG crystal

    Energy Technology Data Exchange (ETDEWEB)

    Hamedi, Hamid Reza, E-mail: hamid.r.hamedi@gmail.com

    2014-06-01

    A novel solid configuration is proposed to achieve a giant Kerr nonlinearity with reduced absorption under conditions of slow light levels. It is shown that an enhanced Kerr nonlinearity accompanied with negligible absorption can be obtained just through the proper tuning of intensity of coherent driving field at C-band telecommunication wavelength which is practical for communication applications. Moreover, the impact of incoherent pump field as well as frequency detuning of coherent field on manipulating the linear and nonlinear optical properties of the yttrium–aluminum-garnet (YAG) crystal medium is discussed. The presented results may be of interest to researchers in the field of all-optical signal processing and solid-state quantum information science.

  18. Studies on growth, crystal structure and characterization of novel organic nicotinium trifluoroacetate single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Dhanaraj, P.V. [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Rajesh, N.P., E-mail: rajeshnp@hotmail.com [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Sundar, J. Kalyana; Natarajan, S. [Department of Physics, Madurai Kamaraj University, Madurai 625 021 (India); Vinitha, G. [Department of Physics, Crescent Engineering College, Chennai 600 048 (India)

    2011-09-15

    Highlights: {yields} Good quality crystals of nicotinium trifluoroacetate in monoclinic system were grown for first time. {yields} Nicotinium trifluoroacetate crystal exhibits third order nonlinear optical properties. {yields} The optical spectrum of nicotinium trifluoroacetate crystal reveals the wide transmission in the entire range with cutoff wavelength at 286 nm. {yields} Nicotinium trifluoroacetate is a low dielectric constant material. - Abstract: An organic material, nicotinium trifluoroacetate (NTF) was synthesized and single crystals in monoclinic system were grown from aqueous solution for the first time. Its solubility and metastable zone width were estimated. The crystal structure of NTF was analyzed to reveal the molecular arrangements and the formation of hydrogen bonds in the crystal. High-resolution X-ray diffraction rocking curve measurements were performed to analyze the structural perfection of the grown crystals. Functional groups in NTF were identified by Fourier transform infrared spectral analysis. Thermal behaviour and stability of NTF were studied by thermogravimetric and differential thermal analysis and differential scanning calorimetry. Mechanical and dielectric properties of NTF crystals were analyzed. Optical studies reveal that NTF crystals are transparent in the wavelength range 286-1100 nm. The third order nonlinear optical parameters of NTF were derived by the Z-scan technique.

  19. The effects of temperature and strain rate on the yielding behavior of the single crystal superalloy PWA 1480

    Science.gov (United States)

    Milligan, Walter W.; Antolovich, Stephen D.

    1988-01-01

    Interrupted tensile tests were conducted on (001) oriented single crystals at temperatures from 20 to 1093 C. Two strain rates were used, 0.5 and 50 percent/min. After the tests, the deformation substructures were characterized by transmission electron microscopy. Results of these tests are given.

  20. Synthesis, growth, morphology of the semiorganic nonlinear optical crystal L-glutamic acid hydrochloride and its structural, thermal and SHG characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Dhanasekaran, P.; Srinivasan, K. [Crystal Growth Laboratory, Department of Physics, School of Physical Sciences, Bharathiar University, Coimbatore-641 046, Tamil Nadu (India)

    2012-12-15

    One of the halide derivatives of L-glutamic acid which was identified as a semiorganic nonlinear optical material, L-glutamic acid hydrochloride [HOOC(CH{sub 2}){sub 2}CH(NH{sub 2})COOH.HCl], was grown as bulk single crystal and its significant properties were characterized. The stoichiometric title compound was synthesized and the solubility of its recrystallized form in DD water was determined in the temperature range 30-80 C by gravimetric method. Structural confirmation was carried out by powder X-ray diffraction study through lattice parameter verification. Optical quality smaller dimension single crystals were grown from aqueous solution by self nucleation through slow evaporation of solvent method and a large dimension single crystal was grown by slow cooling method with reversible seed rotation technique. Morphological importances of different growth facets of the as grown crystals were studied through optical goniometry. Unit cell structure of the grown crystal was refined by single crystal X-ray diffraction analysis, functional groups present in the crystal responsible for various modes of vibrations were confirmed by FTIR spectroscopy analysis, thermal stability of the grown crystal was analysed by TG/DTA and DSC and second harmonic generation (SHG) of a fundamental Nd:YAG laser beam by Kurtz technique. Results indicate that the grown crystal is in stoichiometric composition and has significant improvement in its thermal and SHG properties when compared to pure L-glutamic acid polymorphs. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Hard photon yields from (70-240) GeV electrons incident near axial directions on Si, Ge and W single crystals with a large thickness variation

    Science.gov (United States)

    Medenwaldt, R.; Møller, S. P.; Tang-Petersen, S.; Uggerhøj, E.; Elsener, K.; Hage-Ali, M.; Siffert, P.; Stoquert, J.; Sona, P.; Maier, K.

    1990-06-01

    The dramatic peak found in photon spectra from 150 GeV channelled electrons has for the first time been investigated for 70, 150, and 240 GeV electrons incident on crystals with thickness from 100μ (Si). Very pronounced variations for the high energy part of the photon spectra are found. In Si the photon peak is not found for lower energies and thin crystals. For well-aligned electrons in Si the yield is more than 160 times the Bethe-Heitler one. In general the peak in the photon spectra disaapears for incident angles larger than half the critical angle for channeling. Dramatic radiative energy losses are found along axial directions - in 0.6 mm Ge a 150 GeV electron loses more than 60% of its total energy.

  2. Hard photon yields from (70-240) GeV electrons incident near axial directions on Si, Ge and W single crystals with a large thickness variation

    Energy Technology Data Exchange (ETDEWEB)

    Medenwaldt, R.; Moeller, S.P.; Tang-Petersen, S.; Uggerhoej, E. (Aarhus Univ. (Denmark). Inst. of Physics); Elsener, K. (European Organization for Nuclear Research, Geneva (Switzerland)); Hage-Ali, M.; Siffert, P.; Stoquert, J. (Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires); Sona, P. (Florence Univ. (Italy). Dipt. di Fisica Istituto Nazionale di Fisica Nucleare, Florence (Italy)); Maier, K. (Max-Planck-Institut fuer Metallforschung, Stuttgart (Germany, F.R.))

    1990-06-14

    The dramatic peak found in photon spectra from 150 GeV channelled electrons has for the first time been investigated for 70, 150, and 240 GeV electrons incident on crystals with thicknesses from 100 {mu}m to 1400 {mu}m (Si). Very pronounced variations for the high energy part of the photon spectra are found. In Si the photon peak is not found for lower energies and thin crystals. For well-aligned electrons in Si the yield is more than 160 times the Bethe-Heitler one. In general the peak in the photon spectra disappears for incident angles larger than half the critical angle for channelling. Dramatic radiative energy losses are found along axial directions - in 0.6 mm <110> Ge a 150 GeV electron loses more than 60% of its total energy. (orig.).

  3. A phase-matchable nonlinear optical crystal 4-amino-5-mercapto-3-[1-(4-isobutylphenyl)ethyl]- 1,2,4-triazole: Synthesis, crystal growth and characterization

    Indian Academy of Sciences (India)

    K Naseema; Vijayalakshmi Rao; K V Sujith; Balakrishna Kalluraya

    2009-10-01

    In this paper, we report the synthesis, growth and characterization of a new organic NLO single crystal of 4-amino-5-mercapto-3-[1-(4-isobutylphenyl)ethyl]-1,2,4-triazole (AMIT). The title compound is synthesized and single crystals were grown by the slow evaporation technique at room temperature. The grown crystal was characterized by powder XRD, FTIR, UV–Vis. and microhardness studies. The thermal analysis of the crystal was carried out by TGA, DTA and DSC. From DSC, the melting point of the crystal is found to be 168°C. The scanning electron microscopy (SEM) provides information about the surface morphology of the crystal. The SHG efficiency has been estimated as 0.3 times that of KDP using Kurtz powder method and is found to be a phase-matchable NLO crystal.

  4. Crystal growth, structural, spectral, thermal, linear and nonlinear optical characterization of a new organic nonlinear chiral compound: L-tryptophan-fumaric acid-water (1/1/1) suitable for laser frequency conversion

    Science.gov (United States)

    Peer Mohamed, M.; Jayaprakash, P.; Nageshwari, M.; Rathika Thaya Kumari, C.; Sangeetha, P.; Sudha, S.; Mani, G.; Lydia Caroline, M.

    2017-08-01

    A new organic active nonlinear optical crystal L-tryptophan fumaric acid water (1/1/1), (C15H17N2 O7. H2O)(LTFAW), consisting of zwitterion tryptophan molecule in conjunction with a fumaric acid molecule and a water molecule was grown by slow solvent evaporation technique from aqueous solution. The organic chromophore crystallizes from water in its zwitterions exhibiting tabular habit in monoclinic system with acentric space group C2 (Z = 4). The sharp peaks observed in Powder X-ray diffractogram depicts the crystalline nature. The presence of functional groups in the grown crystal was analyzed using FT-IR spectrum. The carbon and hydrogen environment in molecular structure was investigated using FT-NMR technique using deuterated DMSO solution. Ultraviolet-visible spectral analysis reveal that the crystal possess lower cut-off wavelength down to 275 nm, is a key factor to exhibit Second Harmonic Generation (SHG) signal. The direct optical band gap is evaluated to be 5.28 eV from the UV absorption profile. The evaluation of optical constants by employing UV-visible absorbance data such as, extinction coefficient, reflectance, refractive index, optical conductivity are supportive towards good performance as NLO devices. Temperature of decomposition was investigated using thermogravimetric analysis/differential thermal analysis techniques (TG/DTA). The luminescence profile exhibited two peaks (362 nm, 683 nm) due to the donation of protons from carboxylic group to amino group. The nonlinear optical behavior from the noncentrosymmetric crystal was observed by the generation of frequency doubled (2ω) optical radiation when subjected to pulsed Nd:YAG laser (1064 nm, 10 ns, 10 Hz) using Kurtz-Perry method. The variation of dielectric constant (εʹ) and dielectric loss (εʹʹ) vs. Log f for the title compound was analysed at a few selected temperatures and frequencies.

  5. Multiple exciton generation in nano-crystals revisited: Consistent calculation of the yield based on pump-probe spectroscopy

    CERN Document Server

    Karki, Khadga J; Zheng, Kaibo; Zidek, Karel; Mousa, Abdelrazek; Abdellah, Mohamed A; Messing, Maria; Wallenberg, L Reine; Yartsev, Arkadi; Pullerits, Tonu

    2013-01-01

    Multiple exciton generation (MEG) is a process in which more than one exciton is generated upon the absorption of a high energy photon, typically higher than two times the band gap, in semiconductor nanocrystals. It can be observed experimentally using time resolved spectroscopy such as the transient absorption measurements. Quantification of the MEG yield is usu- ally done by assuming that the bi-exciton signal is twice the signal from a single exciton. Herein we show that this assumption is not always justified and may lead to significant errors in the estimated MEG yields. We develop a methodology to determine proper scaling factors to the signals from the transient absorption experiments. Using the methodology we find modest MEG yields in lead chalcogenide nanocrystals including the nanorods.

  6. Pb{sub 4.7}Ba{sub 0.3}Ge{sub 3}O{sub 11} crystals as new acoustically induced nonlinear optical materials

    Energy Technology Data Exchange (ETDEWEB)

    Zmija, J.; Kaddouri, H. [Perpignan Univ. (France). LP2A; Majchrowski, A.; Mierczyk, Z. [Inst. of Applied Physics, MUT, Warsaw (Poland); Kityk, I.V. [Inst. of Physics Czestochowa (Poland)

    2001-07-01

    Acoustically induced optical second harmonic generation (SHG) and two-photon absorption (TPA) in ferroelectric Pb{sub 4.7}Ba{sub 0.3}Ge{sub 3}O{sub 11} crystals have been found. We have found that with increasing acoustical power, the SHG for YAG:Nd laser light ({lambda}=1.06 {mu}m) increases and achieves its maximum value at acoustical power density about 1.75 W/cm{sup 2}. The evaluated SHG values were 23% less comparing with {chi}{sub 222} tensor of the KDP single crystals. With decreasing temperature, the acoustically induced SHG signal strongly increases below 29 K. The maximal acoustically induced SHG has been observed at acoustical frequencies lying within the ranges 12-17 kHz, 22-23 kHz and above 26 kHz. This behavior reflects nonlinear superposition of the nonlinear optical susceptibilities stimulated by externally-induced electron-phonon anharmonicity. We have observed substantial increase of the TPA (for the acoustical power W= 1.8 W/cm{sup 2}) at high hydrostatic pressures (about 16 GPa) and low temperatures (below 16 K). This one confirms complicated influence of the electron-phonon interactions in the ferroelectrics on the observed nonlinear optical dependences. (orig.)

  7. Crystal chemistry and photomechanical behavior of 3,4-dimethoxycinnamic acid: correlation between maximum yield in the solid-state topochemical reaction and cooperative molecular motion.

    Science.gov (United States)

    Mishra, Manish Kumar; Mukherjee, Arijit; Ramamurty, Upadrasta; Desiraju, Gautam R

    2015-11-01

    A new monoclinic polymorph, form II (P21/c, Z = 4), has been isolated for 3,4-dimethoxycinnamic acid (DMCA). Its solid-state 2 + 2 photoreaction to the corresponding α-truxillic acid is different from that of the first polymorph, the triclinic form I ([Formula: see text], Z = 4) that was reported in 1984. The crystal structures of the two forms are rather different. The two polymorphs also exhibit different photomechanical properties. Form I exhibits photosalient behavior but this effect is absent in form II. These properties can be explained on the basis of the crystal packing in the two forms. The nanoindentation technique is used to shed further insights into these structure-property relationships. A faster photoreaction in form I and a higher yield in form II are rationalized on the basis of the mechanical properties of the individual crystal forms. It is suggested that both Schmidt-type and Kaupp-type topochemistry are applicable for the solid-state trans-cinnamic acid photodimerization reaction. Form I of DMCA is more plastic and seems to react under Kaupp-type conditions with maximum molecular movements. Form II is more brittle, and its interlocked structure seems to favor Schmidt-type topochemistry with minimum molecular movement.

  8. Wide-bandgap nonlinear crystal LiGaSsub>2sub> for femtosecond mid-infrared spectroscopy with chirped-pulse upconversion.

    Science.gov (United States)

    Nakamura, Ryosuke; Inagaki, Yoshizumi; Hata, Hidefumi; Hamada, Norio; Umemura, Nobuhiro; Kamimura, Tomosumi

    2016-11-20

    Femtosecond time-resolved mid-infrared (MIR) spectroscopy based on chirped-pulse upconversion is a promising method for observing molecular vibrational dynamics. A quantitative study on nonlinear media for upconversion is still essential for wide applications, particularly at the frequencies below 2000  cm-1. We evaluate wide-bandgap nonlinear crystals of Li-containing ternary chalcogenides based on their performance as the upconversion medium for femtosecond MIR spectroscopy. The upconversion efficiency is measured as a function of the MIR pulse frequency and the chirped pulse energy. LiGaSsub>2sub> is found to be an efficient crystal for the upconversion of MIR pulses in a wide frequency range of 1100-2700  cm-1, especially below 2000  cm-1. By using LiGaSsub>2sub> as an efficient upconversion crystal, we develop a MIR pump-probe spectroscopy system with a spectral resolution of 2.5  cm-1, a time resolution of 0.2 ps, and a probe window of 120  cm-1. Vibrational relaxation dynamics of CO stretching modes of Mnsub>2sub>(CO)sub>10sub> in cyclohexane and bovine serum albumin in Dsub>2sub>O are demonstrated with a high signal-to-noise ratio.

  9. Energetic mid-IR femtosecond pulse generation by self-defocusing soliton-induced dispersive waves in a bulk quadratic nonlinear crystal

    CERN Document Server

    Zhou, B B; Bache, M

    2014-01-01

    Generating energetic femtosecond mid-IR pulses is crucial for ultrafast spectroscopy, and currently relies on parametric processes that, while efficient, are also complex. Here we experimentally show a simple alternative that uses a single pump wavelength without any pump synchronization and without critical phase-matching requirements. Pumping a bulk quadratic nonlinear crystal (unpoled LiNbO$_3$ cut for noncritical phase-mismatched interaction) with sub-mJ near-IR 50-fs pulses, tunable and broadband ($\\sim 1,000$ cm$^{-1}$) mid-IR pulses around $3.0~\\mu\\rm m$ are generated with excellent spatio-temporal pulse quality, having up to 10.5 $\\mu$J energy (6.3% conversion). The mid-IR pulses are dispersive waves phase-matched to near-IR self-defocusing solitons created by the induced self-defocusing cascaded nonlinearity. This process is filament-free and the input pulse energy can therefore be scaled arbitrarily by using large-aperture crystals. The technique can readily be implemented with other crystals and la...

  10. Synthesis, growth, structural, optical, thermal and mechanical properties of an organic Urea maleic acid single crystals for nonlinear optical applications

    Science.gov (United States)

    Vinothkumar, P.; Kumar, R. Mohan; Jayavel, R.; Bhaskaran, A.

    2016-07-01

    A potential organic urea maleic acid (UMA) was synthesized and single crystals were grown at room temperature by slow evaporation and seed rotation methods. The grown crystal has been subjected to single crystal XRD analysis and found to have been crystallized in a noncentrosymmetric monoclinic crystal system with Cc as space group. The High resolution X-ray diffraction analysis revealed that the specimen is free from structural grain boundaries. The transparency of the grown crystal was confirmed by optical absorption and transmittance spectra with lower cut-off wavelength of 285 nm. The microhardness test was carried out on different planes to study the load dependent hardness values. The dislocation density of the UMA crystal was estimated from the etching studies. The dielectric permittivity and dielectric loss of the grown crystal was carried out as a function of frequency for different temperatures along three crystallographic axes. Thermal properties of UMA crystals were studied by TG-DTA analysis and it is stable upto 112 °C. The laser induced surface damage threshold of the grown crystal was measured using Nd: YAG laser. The birefringence of the crystal measured in the visible region was found to vary with the wavelength. The particle size dependent SHG of the sample was measured with different input energies by Kurtz's powder method using Nd:YAG laser.

  11. Synthesis, crystal growth and characterizations of bis ( l-proline) cadmium iodide: a new semi-organic nonlinear optical material

    Science.gov (United States)

    Boopathi, K.; Jagan, R.; Ramasamy, P.

    2016-07-01

    Novel semi-organic single crystals of bis ( l-proline) cadmium iodide (BLPC) were grown by slow evaporation technique. The crystal structure was determined by single-crystal X-ray diffraction studies. Single-crystal X-ray diffraction study shows that [BLPC] crystallizes in orthorhombic system with space group P212121. 1H NMR and 13C NMR studies were conducted for the grown crystal. Functional groups present in the compound were identified by FTIR spectral studies. The UV-Vis-NIR spectrum was studied to analyse the optical properties of the grown crystals. Thermogravimetric analysis was carried out to study thermal behaviour of the materials. Vickers microhardness measurement was carried out for different loads. Etching studies were carried out using water as etchant. The second harmonic generation efficiency was determined by the Kurtz powder method and it was found to be higher than that of potassium dihydrogen phosphate.

  12. Synthesis, crystal growth and characterization of a chiral compound (triphenylphosphine oxide cadmium iodide): A new semiorganic nonlinear optical material

    Science.gov (United States)

    Santhakumari, R.; Ramamurthi, K.; Stoeckli-Evans, Helen; Hema, R.; Nirmala, W.

    2011-05-01

    Synthesis of semiorganic material, triphenylphosphine oxide cadmium iodide (TPPOCdI), is reported for the first time. Employing the temperature reduction method, a crystal of size 16×7×6 mm 3 was grown from dimethyl sulfoxide (DMSO) solution. Three dimensional crystal structure of the grown crystal was determined by single crystal X-ray diffraction study. The complex crystallizes in the chiral orthorhombic space group P2 12 12 1. FTIR study was carried out in order to confirm the presence of the functional groups. UV-vis-NIR spectral studies show that the crystal is transparent in the wavelength range of 290-1100 nm. The microhardness test was carried out, and the load hardness was measured. Thermogravimetric and differential thermal analyses reveal the thermal stability of the crystal. Second harmonic generation efficiency of the powdered TPPOCdI, tested using Nd: YAG laser, is ∼0.65 times that of potassium dihydrogen orthophosphate.

  13. The nonlinear effect of somatic cell count on milk composition, coagulation properties, curd firmness modeling, cheese yield, and curd nutrient recovery.

    Science.gov (United States)

    Bobbo, T; Cipolat-Gotet, C; Bittante, G; Cecchinato, A

    2016-07-01

    The aim of this study was to investigate the relationships between somatic cell count (SCC) in milk and several milk technological traits at the individual cow level. In particular, we determined the effects of very low to very high SCC on traits related to (1) milk yield and composition; (2) coagulation properties, including the traditional milk coagulation properties (MCP) and the new curd firming model parameters; and (3) cheese yield and recovery of milk nutrients in the curd (or loss in the whey). Milk samples from 1,271 Brown Swiss cows from 85 herds were used. Nine coagulation traits were measured: 3 traditional MCP [rennet coagulation time (RCT, min), curd firming rate (k20, min), and curd firmness after 30 min (a30, mm)] and 6 new curd firming and syneresis traits [potential asymptotic curd firmness at infinite time (CFP, mm), curd firming instant rate constant (kCF, % × min(-1)), syneresis instant rate constant (kSR, % × min(-1)), rennet coagulation time estimated using the equation (RCTeq, min), maximum curd firmness achieved within 45 min (CFmax, mm), and time at achievement of CFmax (tmax, min)]. The observed cheese-making traits included 3 cheese yield traits (%CYCURD, %CYSOLIDS, and %CYWATER, which represented the weights of curd, total solids, and water, respectively, as a percentage of the weight of the processed milk) and 4 nutrient recoveries in the curd (RECFAT, RECPROTEIN, RECSOLIDS, and RECENERGY, which each represented the percentage ratio between the nutrient in the curd and milk). Data were analyzed using a linear mixed model with the fixed effects of days in milk, parity, and somatic cell score (SCS), and the random effect of herd-date. Somatic cell score had strong influences on casein number and lactose, and also affected pH; these were traits characterized by a quadratic pattern of the data. The results also showed a negative linear relationship between SCS and milk yield. Somatic cell score influenced almost all of the tested

  14. Electric field dependence of nonlinearity parameters and third order elastic constants of 0.70Pb(Mg(13)Nb(23))O(3)-0.30PbTiO(3) single crystal.

    Science.gov (United States)

    Liu, Xiaozhou; Zhang, Shujun; Luo, Jun; Shrout, Thomas R; Cao, Wenwu

    2010-02-01

    Through second harmonic measurements, the ultrasonic nonlinearity parameters of [001](c) and [111](c) polarized 0.70Pb(Mg(13)Nb(23))O(3)-0.30PbTiO(3)(PMN-0.3PT) single crystals have been measured as a function of bias electric field. It was found that the nonlinearity parameter increases almost linearly with field at low field but shows a drastic increase near the coercive field. The [111](c) polarized single domain crystal has much smaller nonlinearity parameter than that of the [001](c) polarized multidomain crystal. Based on effective symmetries of these crystals, we were able to derive the field dependence of several third order elastic constants, which are important parameters for high field applications.

  15. Electric field dependence of nonlinearity parameters and third order elastic constants of 0.70Pb(Mg1∕3Nb2∕3)O3–0.30PbTiO3 single crystal

    Science.gov (United States)

    Liu, Xiaozhou; Zhang, Shujun; Luo, Jun; Shrout, Thomas R.; Cao, Wenwu

    2010-01-01

    Through second harmonic measurements, the ultrasonic nonlinearity parameters of [001]c and [111]c polarized 0.70Pb(Mg1∕3Nb2∕3)O3–0.30PbTiO3(PMN–0.3PT) single crystals have been measured as a function of bias electric field. It was found that the nonlinearity parameter increases almost linearly with field at low field but shows a drastic increase near the coercive field. The [111]c polarized single domain crystal has much smaller nonlinearity parameter than that of the [001]c polarized multidomain crystal. Based on effective symmetries of these crystals, we were able to derive the field dependence of several third order elastic constants, which are important parameters for high field applications. PMID:20198132

  16. Energetic mid-IR femtosecond pulse generation by self-defocusing soliton-induced dispersive waves in a bulk quadratic nonlinear crystal

    DEFF Research Database (Denmark)

    Zhou, Binbin; Guo, Hairun; Bache, Morten

    2015-01-01

    and without critical phase-matching requirements. Pumping a bulk quadratic nonlinear crystal (unpoled LiNbO3 cut for noncritical phase-mismatched interaction) with sub-mJ near-IR 50-fs pulses, tunable and broadband (∼ 1,000 cm−1) mid-IR pulses around 3.0 μm are generated with excellent spatio-temporal pulse...... quality, having up to 10.5 μJ energy (6.3% conversion). The mid-IR pulses are dispersive waves phase-matched to near-IR self-defocusing solitons created by the induced self-defocusing cascaded nonlinearity. This process is filament-free and the input pulse energy can therefore be scaled arbitrarily...

  17. Nonlinear excitations and charge transport in lithium niobate crystals investigated using femtosecond-light gratings; Nichtlineare Anregungen und Ladungstransport in Lithiumniobatkristallen untersucht mit Femtosekunden-Lichtgittern

    Energy Technology Data Exchange (ETDEWEB)

    Maxein, Karl Dominik

    2009-12-15

    Lithium niobate (LiNbO{sub 3}) is a widely employed material in nonlinear optics and photonics. Its usage is hampered by the photorefractive effect, which can destroy beam profiles and phase matching conditions. Existing methods to suppress photorefraction fail for the interesting regime of very high intensities and short pulses. Therefore, the photorefractive effect is investigated using femtosecond laser pulses: By utilizing so-called 2K holography, the occupation of energetically shallow traps is observed to occur in less than 100 fs after a two-photon excitation. Writing of photorefractive gratings into oxidized iron-doped LiNbO{sub 3} is much faster with pulses than with cw light. This is explained by the sensitization of the crystal due to charge trapping in photorefractive centers after nonlinear excitations. Finally, light-induced scattering of pulse light is suppressed compared to the scattering of cw light due to the small coherence length of pulses. (orig.)

  18. Wavelength conversion of a 40 Gb/s RZ-DPSK signal using four-wave mixing in a dispersion-flattened highly nonlinear photonic crystal fiber

    DEFF Research Database (Denmark)

    Andersen, Peter Andreas; Tokle, Torger; Geng, Yan

    2005-01-01

    by the gain bandwidth of erbium-doped fiber amplifiers, are obtained in only 50-m dispersion-flattened HNL-PCF with nonlinear coefficient equal to 11 W-1·km-1. This experiment demonstrates the potential of four-wave mixing in HNL-PCF as a modulation format and bit rate transparent wavelength conversion......Wavelength conversion of a 40-Gb/s return-to-zero differential phase-shift keying signal is demonstrated in a highly nonlinear photonic crystal fiber (HNL-PCF) for the first time. A conversion efficiency of -20 dB for a pump power of 23 dBm and a conversion bandwidth of 31 nm, essentially limited...

  19. Broad optical bandwidth based on nonlinear effect of intensity and phase modulators through intense four-wave mixing in photonic crystal fiber

    Science.gov (United States)

    Eltaif, Tawfig

    2017-05-01

    This work investigates the advantages of nonlinear optics of a cascaded intensity modulator (IM) and phase modulator (PM) to generate an initial optical frequency comb. The results show that when the direct current bias to amplitude ratio, α=0.1, and the IM and PM have the same modulation index and are equal 10, seed comb is achieved; it is generated by the modulation of two continuous wave lasers. Hence, based on these parameters, an intense four-wave mixing is created through 9 m of photonic crystal fiber. Moreover, a broadband spectrum was achieved, spaced by a 30-GHz microwave frequency.

  20. Electro- and thermo-optic effects on multi-wavelength Solc filters based on chi(2) nonlinear quasi-periodic photonic crystals.

    Science.gov (United States)

    Kee, Chul-Sik; Lee, Yeong Lak; Lee, Jongmin

    2008-04-28

    We investigate electro- and thermo-optic effects on multi-wavelength Solc filters based on chi(2) nonlinear quasi-periodic photonic crystals. The multi-wavelength Solc filters are composed of two building blocks A and B, in which each containing a pair of antiparallel poled domains, arranged as a Fibonacci sequence. The transmittances at filtering wavelengths can be modulated from 0 to 100% by applying an external voltage but the filtering wave-lengths are unchanged. The filtering wavelengths can be tuned by varying temperature. As temperature decreases, the filtering wavelengths increase (approximately -0.45 nm/degrees C).

  1. Generating mid-IR octave-spanning supercontinua and few-cycle pulses with solitons in phase-mismatched quadratic nonlinear crystals

    DEFF Research Database (Denmark)

    Bache, Morten; Guo, Hairun; Zhou, Binbin

    2013-01-01

    of the promising crystals: in one case soliton pulse compression from 50 fs to 15 fs (1.5 cycles) at 3.0 μm is achieved, and at the same time a 3-cycle dispersive wave at 5.0 μm is formed that can be isolated using a long-pass filter. In another example we show that extremely broadband supercontinua can form......We discuss a novel method for generating octave-spanning supercontinua and few-cycle pulses in the important mid-IR wavelength range. The technique relies on strongly phase-mismatched cascaded second-harmonic generation (SHG) in mid-IR nonlinear frequency conversion crystals. Importantly we here...

  2. A 7.81 W 355 nm ultraviolet picosecond laser using La2CaB10O19 as a nonlinear optical crystal.

    Science.gov (United States)

    Zhang, Ling; Li, Kai; Xu, Degang; Yu, Haijuan; Zhang, Guochun; Wang, Yuye; Wang, Lirong; Shan, Faxian; Yan, Chao; Yang, Yingying; Wang, Baohua; Wang, Nan; Lin, Xuechun; Wu, Yicheng; Yao, Jianquan

    2014-07-14

    We demonstrate high-power 355 nm ultraviolet (UV) picosecond (ps) laser using a type I phase-matching nonlinear optical crystal of La(2)CaB(10)O(19) (LCB), which possesses the characteristic of non-hygroscopicity. The high-power third harmonic generation was successfully achieved from two types of 1064 nm ps fundamental lasers. The maximum output power of 7.81 W of 355 nm UV laser was obtained with a pump of 35.2 W 1064 nm ps laser (80 MHz repetition rate, 10 ps pulse width) with optical conversion efficiency of 22.2%. The experimental results show that the LCB crystal is a promising candidate for generating high-power UV laser.

  3. Frequency down-conversion of 1 μm laser radiation to the mid-IR using non-oxide nonlinear crystals in a cascaded intracavity configuration

    Science.gov (United States)

    Petrov, Valentin; Boyko, Andrey A.; Kostyukova, Nadezhda Y.; Marchev, Georgi M.; Pasiskevicius, Valdas; Kolker, Dmitry B.; Badikov, Valeriy; Badikov, Dmitrii; Shevyrdyaeva, Galina; Zukauskas, Andrius; Panyutin, Vladimir

    2017-02-01

    A singly-resonant OPO (SRO) based on AgGaSe2 (AGSe) intracavity pumped at 1.85 μm by the signal pulses of a Rb:PPKTP doubly-resonant OPO (DRO) provided extremely broad tuning (5.8 to 18 μm) for the non-resonated idler. In a similar set-up with the same nonlinear crystals, we studied intracavity difference-frequency generation (DFG). Both AGSe and the new monoclinic crystal BaGa4Se7 (BGSe) generated single pulse energies of 0.7 mJ near 7 μm at an overall conversion efficiency from the 1.064 μm pump of 1.2%. The main advantage of BGSe is its damage resistivity up to the maximum pump levels applied at 100 Hz.

  4. Growth, spectral, thermal, laser damage threshold, microhardness, dielectric, linear and nonlinear optical properties of an organic single crystal: L-phenylalanine DL-mandelic acid

    Energy Technology Data Exchange (ETDEWEB)

    Jayaprakash, P. [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604 407, Tamil Nadu (India); Peer Mohamed, M. [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604 407, Tamil Nadu (India); Department of Physics, C. Abdul Hakeem College, Melvisharam 632 509, Tamil Nadu (India); Krishnan, P. [Department of Physics, St. Joseph’s College of Engineering, Chennai 600 119, Tamil Nadu (India); Nageshwari, M.; Mani, G. [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604 407, Tamil Nadu (India); Lydia Caroline, M., E-mail: lydiacaroline2006@yahoo.co.in [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604 407, Tamil Nadu (India)

    2016-12-15

    Single crystals of L-phenylalanine dl-mandelic acid [C{sub 9}H{sub 11}NO{sub 2}. C{sub 8}H{sub 8}O{sub 3}], have been grown by the slow evaporation technique at room temperature using aqueous solution. The single crystal XRD study confirms monoclinic system for the grown crystal. The functional groups present in the grown crystal have been identified by FTIR and FT-Raman analyses. The optical absorption studies show that the crystal is transparent in the visible region with a lower cut-off wavelength of 257 nm and the optical band gap energy E{sub g} is determined to be 4.62 eV. The Kurtz powder second harmonic generation was confirmed using Nd:YAG laser with fundamental wavelength of 1064 nm. Further, the thermal studies confirmed no weight loss up to 150°C for the as-grown crystal. The photoluminescence spectrum exhibited three peaks (414 nm, 519 nm, 568 nm) due to the donation of protons from carboxylic acid to amino group. Laser damage threshold value was found to be 4.98 GW/cm{sup 2}. The Vickers microhardness test was carried out on the grown crystals and there by Vickers hardness number (H{sub v}), work hardening coefficient (n), yield strength (σ{sub y}), stiffness constant C{sub 11} were evaluated. The dielectric behavior of the crystal has been determined in the frequency range 50 Hz–5 MHz at various temperatures.

  5. Organic nonlinear optical materials

    Science.gov (United States)

    Umegaki, S.

    1987-01-01

    Recently, it became clear that organic compounds with delocalized pi electrons show a great nonlinear optical response. Especially, secondary nonlinear optical constants of more than 2 digits were often seen in the molecular level compared to the existing inorganic crystals such as LiNbO3. The crystallization was continuously tried. Organic nonlinear optical crystals have a new future as materials for use in the applied physics such as photomodulation, optical frequency transformation, opto-bistabilization, and phase conjugation optics. Organic nonlinear optical materials, e.g., urea, O2NC6H4NH2, I, II, are reviewed with 50 references.

  6. Growth, Properties, and Theoretical Analysis of M2LiVO4 (M = Rb, Cs) Crystals: Two Potential Mid-Infrared Nonlinear Optical Materials.

    Science.gov (United States)

    Han, Guopeng; Wang, Ying; Su, Xin; Yang, Zhihua; Pan, Shilie

    2017-05-15

    Mid-Infrared nonlinear optical (Mid-IR NLO) crystals with excellent performances play a particularly important role for applications in areas such as telecommunications, laser guidance, and explosives detection. However, the design and growth of high performance Mid-IR NLO crystals with large NLO efficiency and high laser-damage threshold (LDT) still face numerous fundamental challenge. In this study, two potential Mid-IR NLO materials, Rb2LiVO4 (RLVO) and Cs2LiVO4 (CLVO) with noncentrosymmetric structures (Orthorhombic, Cmc21) were synthesized by high-temperature solution method. Thermal analysis and powder X-ray diffraction demonstrate that RLVO and CLVO melt congruently. Centimeter sized crystals of CLVO have been grown by the top-seeded solution growth method. RLVO and CLVO exhibit strong second harmonic generation (SHG) effects (about 4 and 5 times that of KH2PO4, respectively) with a phase-matching behavior at 1.064 μm, and a wide transparency range (0.33-6.0 μm for CLVO). More importantly, RLVO and CLVO possess a high LDT value (~28 × AgGaS2). In addition, the density functional theory (DFT) and dipole moments studies indicate that the VO4 anionic groups have a dominant contribution to the SHG effects in RLVO and CLVO. These results suggest that the title compounds are promising NLO candidate crystals applied in the Mid-IR region.

  7. Synthesis, Crystal Structure, and Nonlinear Optical Properties of a New Alkali and Alkaline Earth Metal Carbonate RbNa5Ca5(CO38

    Directory of Open Access Journals (Sweden)

    Qiaoling Chen

    2016-12-01

    Full Text Available A new nonlinear optical (NLO material, RbNa5Ca5(CO38, has been synthesized by the hydrothermal method. The crystal structure is established by single-crystal X-ray diffraction. RbNa5Ca5(CO38 crystallizes in the hexagonal crystal system with space group P63mc (No. 186. The structure of RbNa5Ca5(CO38 can be described as the adjacent infinite [CaCO3]∞ layers lying in the a-b plane bridged through standing-on-edge [CO3] groups by sharing O atoms (two-fold coordinated to build a framework with four types of tunnels running through the b-axis. The Rb, Na, and [Na0.67Ca0.33] atoms reside in these tunnels, respectively. The measurement of second harmonic generation (SHG indicated that RbNa5Ca5(CO38 is a phase-matchable material, which had SHG responses of approximately 1×KH2PO4 (KDP. Meanwhile, the results from the UV-VIS diffuse reflectance spectroscopy study of the powder samples indicated that the UV cut-off edges of RbNa5Ca5(CO38 is about 203 nm.

  8. Chemical synthesis, crystal structure, vibrational spectroscopy, non-linear optical properties and DFT calculation of bis (2,6-diaminopyridinium) sulfate monohydrate

    Science.gov (United States)

    Ben Hassen, Chaouki; Dammak, Thameur; Chniba-Boudjada, Nassira; Mhiri, Tahar; Boujelbene, Mohamed

    2017-01-01

    Single crystals of a new organic inorganic hybrid compound "bis (2,6-diaminopyridinium) sulfate monohydrate [C5H8N3]2SO4·H2O ([2,6-HDAP]2SO4·H2O)" was synthesized by slow evaporation method at room temperature and characterized by X-ray single crystal diffraction, infrared spectroscopy and DFT calculation. The new hybrid compound crystallizes in the orthorhombic system with the non-centro symmetric space group Pna21 and the following parameters a = 14.759(2) Å, b = 7.076 (2) Å and c = 28.159 (2) Å. The atomic arrangement can be described as inorganic chains following the b axis connected with the organic groups by means of Nsbnd H⋯O hydrogen bonds to form 3D network. Antiparallelly π-π stacked 2,6-HDAP cations form molecular columns in the spaces between the chains. The optimized molecular structure, vibrational spectra and the optical properties were calculated by the density functional theory (DFT) method using the B3LYP function with the LanL2DV basis set. The wavenumber calculated are in good agreement with the observed frequency values. The calculated hyperpolarizability βtot is about 4.5 times more than that of the reference crystal KDP. Hence, the large β value shows that the title compound is an attractive object for future studies of nonlinear optical properties.

  9. Spectral, optical and mechanical studies on L-histidine hydrochloride monohydrate (LHC) single crystals grown by unidirectional growth technique

    Energy Technology Data Exchange (ETDEWEB)

    Robert, R. [Department of Physics, Government Arts College (Men), Krishnagiri (India); Justin Raj, C. [Department of Physics, Loyola College, Chennai 600 034 (India); Krishnan, S. [Department of Physics, R.M.K. Engineering College, Kavaripettai 601 206 (India); Uthrakumar, R.; Dinakaran, S. [Department of Physics, Loyola College, Chennai 600 034 (India); Jerome Das, S., E-mail: sjeromedas2004@yahoo.co [Department of Physics, Loyola College, Chennai 600 034 (India)

    2010-08-15

    Single crystals of nonlinear optical L-histidine hydrochloride monohydrate (LHC) were grown in an aqueous solution by the unidirectional crystal growth method within a period of 45 days along (1 0 1) plane. The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm their orthorhombic structure having space group P2{sub 1}2{sub 1}2{sub 1}. Values of several physical parameters were determined for the grown crystal. Optical transmission studies revealed very low absorption and band gap energy was calculated for the LHC crystals. Further, some optical constant were also determined for the grown crystals. Anisotropy in Vicker's microhardness led to the assessment of fracture toughness, brittleness index and yield strength for the synthesized crystals. Nonlinear optical studies were carried out for the grown crystal and second harmonic generation (SHG) efficiency was found to be three times that of KDP crystals.

  10. Growth and characterization of nonlinear optical single crystals: bis(cyclohexylammonium) terephthalate and cyclohexylammonium para-methoxy benzoate

    Indian Academy of Sciences (India)

    P Sathya; M Anantharaja; N Elavarasu; R Gopalakrishnan

    2015-09-01

    Bis(cyclohexylammonium) terephthalate (BCT) and cyclohexylammonium 4-methoxy benzoate (C4MB) single crystals were successfully grown by the slow evaporation solution growth technique. The harvested crystals were subjected to single-crystal X-ray diffraction, spectral, optical, thermal and mechanical studies in order to evaluate physiochemical properties. The Kurtz and Perry technique for second harmonic generation (SHG) study revealed that the powdered materials of BCT and C4MB exhibit SHG efficiency 0.2 times less and 1.3 times greater than that of standard reference material potassium dihydrogen phosphate. C4MB crystal exhibits high efficiency than BCT, because of methoxy group substituted in the para position of phenyl ring. With high SHG efficiency and thermal stability para substituted C4MB crystal will be a potential candidate for optical device fabrication.

  11. Extraction mechanism of ultrasound assisted extraction and its effect on higher yielding and purity of artemisinin crystals from Artemisia annua L. leaves.

    Science.gov (United States)

    Chemat, Smain; Aissa, Abdallah; Boumechhour, Abdenour; Arous, Omar; Ait-Amar, Hamid

    2017-01-01

    This study proposes an ultrasound-horn system for the extraction of a natural active compound "artemisinin" from Artemisia annua L. leaves as an alternative to hot maceration technique. Ultrasound leaching improves artemisinin recovery at all temperatures where only ten minutes is required to recover 70% (4.42mgg(-1)) compared to 60min of conventional hot leaching for the same yield. For instance, ultrasound treatment at 30°C produced a higher yield than the one obtained by conventional maceration at 40°C. Kinetic study suggests that the extraction pattern can be assimilated, during the first ten minutes, to a first order steady state, from which activation energy calculations revealed that each gram of artemisinin required 7.38kJ in ultrasound versus 10.3kJ in the conventional system. Modeling results indicate the presence of two extraction stages, a faster stage with a diffusion coefficient of 19×10(-5)cm(2)min(-1) for ultrasound technique at 40°C, seven times higher than the conventional one; and a second deceleration stage similar for both techniques with diffusion coefficient ranging from 1.7 to 3.1×10(-5)cm(2)min(-1). It is noted that the efficient ultrasound extraction potential implies extraction of higher amount of co-metabolites so low artemisinin crystal purity is engendered but a combination with a purification step using activated charcoal and celite adsorbents produced crystals with comparable purity for conventional and ultrasound samples.

  12. Withdrawal of Chinese Physics Letters 26 (2009) 114209 "A Sensitive Scheme to Observe Weak Photo-Refraction Effects in Some Nonlinear Optical Crystals Pumped by Ultrashort Optical Pulses"

    Institute of Scientific and Technical Information of China (English)

    XU Shi-Xiang

    2011-01-01

    @@ This paper has been retracted because Fig.2 is copied from an earlier paper, "Interband photorefrac- tive effect in β-BBO crystal due to multiphoton exci- tation by intense ultrashort optical pulses" by Shix- iang Xu et al., which appeared in Optics Express 15 (2007) 10576, and its Figs.3 and 4 also present simi- lar data as in Figs.3 and 4 of the same Optics Express paper though they are measured at a different pump- ing power.This paper includes the first meaningful measurements of the photorefractive effect in BIBO and LBO crystals by intense ultrashort optical pulses, the first explanation of the phase-matching effect on the measurement of the photorefractive effect in BBO crystal and the reduction of pumping beam intensity of the second harmonic generator in the experimental setup to mitigate the effect of the nonlinear instability on our measurements.However, I admit, the Chinese Physics Letter paper contains serious replication with- out proper citation.%This paper has been retracted because Fig. 2 is copied from an earlier paper, "Interband photorefrac-tive effect in /3-BBO crystal due to multiphoton excitation by intense ultrashort optical pulses" by Shix-iang Xu et al, which appeared in Optics Express 15 (2007) 10576, and its Figs. 3 and 4 also present similar data as in Figs. 3 and 4 of the same Optics Express paper though they are measured at a different pumping power. This paper includes the first meaningful measurements of the photorefractive effect in BIBO and LBO crystals by intense ultrashort optical pulses, the first explanation of the phase-matching effect on the measurement of the photorefractive effect in BBO crystal and the reduction of pumping beam intensityof the second harmonic generator in the experimental setup to mitigate the effect of the nonlinear instability on our measurements. However, I admit, the Chinese Physics Letter paper contains serious replication without proper citation.I am so sorry for my faults and nescience. I alone

  13. 4-N, N-bis(4-methoxylphenyl) aniline substituted anthraquinone: X-ray crystal structures, theoretical calculations and third-order nonlinear optical properties

    Science.gov (United States)

    Xu, Liang; Zhang, Dingfeng; Zhou, Yecheng; Zheng, Yusen; Cao, Liu; Jiang, Xiao-Fang; Lu, Fushen

    2017-08-01

    In this paper, mono- and di-4-N,N-bis(4-methoxylphenyl)aniline-substituted anthraquinone have been designed and synthesized through Suzuki reaction. For mono-4-N,N-bis(4-methoxylphenyl)aniline-substituted anthraquinone, polymorphous crystal structures have been obtained in different crystallization conditions. Electrochemical characterization combined with theoretical calculation suggests that the addition of a second triphenylamine unit causes a larger band gap with higher lying LUMO (Lowest Unoccupied Molecular Orbital) and HOMO (Highest Occupied Molecular Orbital). The linear optical property shows that the introduction of a second triphenylamine unit bring about a significant hyperchromic effect with the extinction coefficients increasing from 11199 M-1 cm-1 to 22136 M-1 cm-1. The third-order nonlinear optical properties indicate that the introduction of a second triphenylamine unit lead to a much larger nonlinear absorption coefficient and two-photon absorption cross section, with the relevant value increasing from 2.04 × 10-12 cm W-1 to 3.91 × 10-12 cm W-1, and from 148 GM to 286 GM, respectively.

  14. Application of Z-scan technique for the study of nonlinear absorption in chemically reduced LiNbO3 crystals

    Science.gov (United States)

    Kostritskii, SM; Aillerie, M.; Kokonyan, E.; Sevostyanov, OG

    2017-07-01

    The nonlinear absorption (NLA) was studied by open-aperture Z-scan experiments in the chemically reduced nominally pure LiNbO3 crystals at cw-illumination with the red (644 nm) and green (514.5 nm) laser beams. The magnitude of the measured NLA is considerably different from the reported Z-scan results obtained in as-grown LiNbO3. The positive sign of NLA obtained with the red light has been related to the generation of the small bound polarons absorbing in red and near-IR ranges. Application of green light results in the light-induced transparency, i.e. the Z-scan traces show negative sign of NLA. Intensity dependence of Z-scan traces allows for conclusion that the photo-induced dissociation of small NbLi 4+:NbNb 4+ bipolarons and sequent generation of small polarons gives the dominating contribution to the nonlinear optical absorption in reduced crystals with a large bipolarons concentration.

  15. Successive approximation-like 4-bit full-optical analog-to-digital converter based on Kerr-like nonlinear photonic crystal ring resonators

    Science.gov (United States)

    Tavousi, Alireza; Mansouri-Birjandi, Mohammad Ali; Saffari, Mehdi

    2016-09-01

    Implementing of photonic sampling and quantizing analog-to-digital converters (ADCs) enable us to extract a single binary word from optical signals without need for extra electronic assisting parts. This would enormously increase the sampling and quantizing time as well as decreasing the consumed power. To this end, based on the concept of successive approximation method, a 4-bit full-optical ADC that operates using the intensity-dependent Kerr-like nonlinearity in a two dimensional photonic crystal (2DPhC) platform is proposed. The Silicon (Si) nanocrystal is chosen because of the suitable nonlinear material characteristic. An optical limiter is used for the clamping and quantization of each successive levels that represent the ADC bits. In the proposal, an energy efficient optical ADC circuit is implemented by controlling the system parameters such as ring-to-waveguide coupling coefficients, the ring's nonlinear refractive index, and the ring's length. The performance of the ADC structure is verified by the simulation using finite difference time domain (FDTD) method.

  16. Wavelength conversion, time demultiplexing and multicasting based on cross-phase modulation and four-wave mixing in dispersion-flattened highly nonlinear photonic crystal fiber

    Science.gov (United States)

    Hui, Zhan-Qiang; Zhang, Jian-Guo

    2012-05-01

    We propose the use of cross-phase modulation (XPM) and four-wave mixing (FWM) in dispersion-flattened highly nonlinear photonic crystal fibers (HNL-PCFs) to implement the functionalities of wavelength conversion, simultaneous time demultiplexing and wavelength multicasting in optical time-division multiplexing (OTDM) systems. The experiments on wavelength conversion at 80 Gbit s-1and OTDM demultiplexing from 80 to 10 Gbit s-1 with wavelength multicasting of two channels are successfully demonstrated to validate the proposed scheme, which are carried out by using two segments of dispersion-flattened HNL-PCFs with lengths of 100 and 50 m, respectively. Moreover, the bit error rate (BER) performance is also measured. The results show that our designed system can achieve a power penalty of less than 4.6 dB for two multicasting channels with a 24 nm wavelength span at the BER of 10-9 when compared with the 10 Gbit/s back-to-back measurement. The proposed system is transparent to bit rate since only an ultrafast third-order nonlinear effect is used. The resulting configuration is compact, robust and reliable, benefiting from the use of dispersion-flattened HNL-PCFs with short lengths. This also makes the proposed system more flexible in the operational wavelengths than those based on dispersion-shifted fibers and traditional highly nonlinear fibers. The work was supported in part by the CAS/SAFEA International Partnership Program for Creative Research Teams.

  17. Investigations on growth, structure, optical properties and laser damage threshold of organic nonlinear optical crystals of Guanidinium L-Ascorbate

    Science.gov (United States)

    Saripalli, Ravi K.; Kumar, Sanath; Bhat, H. L.; Elizabeth, Suja

    2015-05-01

    Single crystals of Guanidinium L-Ascorbate (GuLA) were grown and crystal structure was determined by direct methods. GuLA crystallizes in orthorhombic, non-centrosymmetric space group P212121. The UV-cutoff was determined as 325 nm. The morphology was generated and the interplanar angles estimated and compared with experimental values. Second harmonic generation conversion efficiency was measured and compared with other salts of L-Ascorbic acid. Surface laser damage threshold was calculated as 11.3GW/cm2 for a single shot of laser of 1064 nm wavelength.

  18. High-pressure crystal structure of the non-linear optical compound BiB(3)O(6) from two-dimensional powder diffraction data.

    Science.gov (United States)

    Dinnebier, R E; Hinrichsen, B; Lennie, A; Jansen, M

    2009-02-01

    Our recently proposed method for automatic detection, calibration and evaluation of Debye-Scherrer ellipses using pattern-recognition techniques and advanced signal filtering was applied to the two-dimensional powder diffraction data of the non-ferroelectric, non-centrosymmetric non-linear optical (NLO) compound alpha-BiB(3)O(6) as a function of pressure. At ambient conditions, alpha-BiB(3)O(6) crystallizes in the space group C2 (phase I). In the pressure range between P = 6.09 and 6.86 GPa, it exhibits a first-order phase transition into a structure with the space group C1 (P1) [phase II at P = 8.34 GPa: a = 7.4781 (6), b = 3.9340 (4), c = 6.2321 (6) A, alpha = 93.73 (1), beta = 102.93 (1), gamma = 90.76 (1) degrees , and V = 178.24 (3) A(3)]. Non-linear compression behaviour over the entire pressure range is observed, which can be described by two Vinet relations in the ranges from P = 0.0 to 6.09 GPa, and from P = 6.86 to 11.6 GPa. The extrapolated bulk moduli of the high-pressure phases were determined to be K(0) = 38 (1) GPa for phase I, and K(0) = 114 (10) GPa for phase II. The crystal structures of both phases were refined against X-ray powder diffraction data measured at several pressures between 0.0 and 11.6 GPa. The structural phase transition of alpha-BiB(3)O(6) is mainly characterized by a reorientation of the [BO(3)](3-) triangles, the [BO(4)](5-) tetrahedra and the lone electron pair which is localized at Bi(3+), in order to optimize crystal packing.

  19. Numerical analysis of near and far field patterns of second-harmonic generation with tiling nonlinear optical crystals

    Energy Technology Data Exchange (ETDEWEB)

    Harimoto, T [Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11 Kofu, Yamanashi 400-8511 (Japan); Shiraga, H [Institute of Laser Engineering, Osaka University, Suita, Osaka (Japan)], E-mail: harimoto@yamanashi.ac.jp

    2008-05-01

    We report numerical analysis of near- and far-field patterns of the second-harmonic wave in a large-scale high-power laser used in the laser fusion with type I KDP crystals arranged in a tiling style. The thickness and phase-matching angle of the tiling crystals are designed based on the near-field pattern of the second-harmonic wave. The tilting angle error and thickness difference of the tiling crystals are evaluated by the energy distribution included in the Airy spot of the far-field pattern at the focal point. The parallelism and flatness of the tiling crystals can also be estimated with the same method.

  20. Synthesis, structural, optical, thermal and dielectric studies on new organic nonlinear optical crystal by solution growth technique.

    Science.gov (United States)

    Prakash, M; Geetha, D; Lydia Caroline, M

    2013-04-15

    Single crystals of L-phenylalanine-benzoic acid (LPBA) were successfully grown from aqueous solution by solvent evaporation technique. Purity of the crystals was increased by the method of recrystallization. The XRD analysis confirms that the crystal belongs to the monoclinic system with noncentrosymmetric space group P21. The chemical structure of compound was established by FT-NMR technique. The presence of functional groups was estimated qualitatively by Fourier transform infrared analysis (FT-IR). Ultraviolet-visible spectral analyses showed that the crystal has low UV cut-off at 254 nm combined with very good transparency of 90% in a wide range. The optical band gap was estimated to be 6.91 eV. Thermal behavior has been studied with TGA/DTA analyses. The existence of second harmonic generation (SHG) efficiency was found to be 0.56 times the value of KDP. The dielectric behavior of the sample was also studied for the first time.

  1. 80 Gb/s transmission over 80 km and demultiplexing using a highly non-linear photonic crystal fibre

    DEFF Research Database (Denmark)

    Berg, Kim Skaalum; Oxenløwe, Leif Katsuo; Siahlo, Andrei;

    2002-01-01

    We report on, transmission of an 80 Gb/s signal over 80 km of standard single mode fibre with subsequent demultiplexing to 10 Gb/s in a NOLM containing a novel photonic crystal fibre......We report on, transmission of an 80 Gb/s signal over 80 km of standard single mode fibre with subsequent demultiplexing to 10 Gb/s in a NOLM containing a novel photonic crystal fibre...

  2. Synthesis, growth, optical and anisotropic mechanical behaviour of organic nonlinear optical imidazolium 2-chloro-4-nitrobenzoate single crystals

    Science.gov (United States)

    Krishnakumar, Varadharajan; Jayaprakash, Jeyaram; Boobas, Singaram; Komathi, Muniraj

    2016-10-01

    The title compound, imidazolium 2-chloro-4-nitrobenzoate (I2C4NB), has been synthesized and optical quality single crystals were grown with a dimension of 4 × 2 × 1 mm3 using an ethanol and acetone (1:1) mixed solvent by slow evaporation solution growth technique. The powder XRD analysis confirmed the crystal structure and found that it is crystallized in the non-centrosymmetric space group P21 with the monoclinic system. The symmetries of molecular vibrations were confirmed by FT-IR spectrum. The CHN(S) analysis confirmed the stoichiometric composition of the grown crystal. It also exhibits a good transparency in the entire visible region (300-800nm) and it was thermally stable up to 131.1 °C. The microhardness measurement shows the anisotropic nature of I2C4NB and also that it belongs to a soft material category. Photoconductivity studies reveal a linear increase of the photocurrent with respect to the applied electric field. HOMO LUMO studies were carried out for the crystal. The second harmonic generation test by the Kurtz powder method shows that the crystal exhibits phase matching and a conversion efficiency which is 2 times that of KDP.

  3. Synthesis, crystal structure refinement, and nonlinear-optical properties of CaB{sub 3}O{sub 5}(OH): Comparative crystal chemistry of calcium triborates

    Energy Technology Data Exchange (ETDEWEB)

    Yamnova, N. A., E-mail: aks.crys@gmail.com; Aksenov, S. M. [Moscow State University, Faculty of Geology (Russian Federation); Stefanovich, S. Yu. [Moscow State University, Faculty of Chemistry (Russian Federation); Volkov, A. S.; Dimitrova, O. V. [Moscow State University, Faculty of Geology (Russian Federation)

    2015-09-15

    Calcium triborate CaB{sub 3}O5(OH) obtained by hydrothermal synthesis in the Ca(OH){sub 2}–H{sub 3}BO{sub 3}–Na{sub 2}CO{sub 3}–KCl system is studied by single-crystal X-ray diffraction. The parameters of the orthorhombic unit cell are as follows: a = 13.490(1), b = 6.9576(3), and c = 4.3930(2) Å; V = 412.32(3) Å{sup 3} and space group Pna2{sub 1}. The structure is refined in the anisotropic approximation of the atomic displacement parameters to R = 4.28% using 972 vertical bar F vertical bar > 4σ(F). It is confirmed that the crystal structure of Ca triborate CaB{sub 3}O{sub 5}(OH) is identical to that described earlier. The hydrogen atom is localized. An SHG signal stronger than that of the quartz standard is registered. The phase transition of calcium triborate into calciborite is found on heating. The comparative crystal-chemical analysis of a series of borates with the general chemical formula 2CaO · 3B{sub 2}O{sub 3} · nH{sub 2}O (n = 0–13) with the constant CaO: B{sub 2}O{sub 3}= 2: 3 ratio and variable content of water is performed.

  4. Nonlinear Optical Terahertz Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our approach is based on high-Q optical WGM resonators made with a nonlinear crystal. Such resonators have been demonstrated to dramatically enhance nonlinear...

  5. Phase retrieval using nonlinear diversity.

    Science.gov (United States)

    Lu, Chien-Hung; Barsi, Christopher; Williams, Matthew O; Kutz, J Nathan; Fleischer, Jason W

    2013-04-01

    We extend the Gerchberg-Saxton algorithm to phase retrieval in a nonlinear system. Using a tunable photorefractive crystal, we experimentally demonstrate the noninterferometric technique by reconstructing an unknown phase object from optical intensity measurements taken at different nonlinear strengths.

  6. Studies on Inverse Opal and Two-Dimensional Nonlinear Photonic Crystals%反Opal及二维非线性光子晶体的研究

    Institute of Scientific and Technical Information of China (English)

    倪培根; 程丙英; 张道中

    2006-01-01

    通过向SiO2 Opal模板中填充钛酸乙酯制备TiO2光子晶体,观测到光子晶体带隙位置的移动达62nm,并发现光子晶体的有序度随填充率的升高而下降.向聚苯乙烯Opal模板中填充钛酸乙酯,制备成当时填充率最高、带隙最短的紫外波段TiO2反Opal光子晶体(中心波长~380nm),并根据测量的其透射谱估算出其填充率约为12%,即Opal模板孔隙的50%被填充.本文还对二维PPLN光子晶体进行了研究.建立了一套高压极化装置和电压数据采集装置,通过外加电场极化法成功制备出了具有正方形和矩形两种晶格形状二维PPLN光子晶体.利用二维PPLN的二阶准相位匹配,测量了其对1.064μm激光的二次谐波转换效率,并研究了晶体的温度、激光的入射角度及占空比对二次谐波转换效率的影响.利用矩形晶格实现了多方向、多波长倍频高效输出.%In this paper, we report some results on inverse opal photonic crystal and two-dimensional periodically poled lithium niobate photonic crystal. First, the process of infiltrating TiO2 into SiO2 Opal was systematically studied. Because of the infiltration of TiO2, the gap of SiO2 Opal was shifted to longer wavelength and a maximum shift of 62nm was observed. Furthermore, an inverse TiO2 Opal with larger filling fraction, ~ 12%, was fabricated, whose band gap in the Γ-L direction is located in the ultraviolet region ( ~ 380nm). Then two-dimensional nonlinear photonic crystals of lithium nlobate with uniform square lattices were fabricated by applying external electric fields. The variations of second-harmonic output with crystal temperatures, incident angles and reversed duty cycles were measured. Red, yellow,green, blue, and violet coherent radiations were generated in the nonlinear photonic crystal with rectangular lattice in the collinearly and non-collinearly quasi-phase matching geometries. The results showed that two-dimensional nonlinear photonic crystal

  7. Construction of the Crystal Ball detector system and study of the helicity asymmetry in {gamma}p{yields}p{pi}{sup 0}{pi}{sup 0}; Aufbau des Crystal Ball-Detektorsystems und Untersuchung der Helizitaetsasymmetrie in {gamma} p {yields} p {pi}{sup 0} {pi}{sup 0}

    Energy Technology Data Exchange (ETDEWEB)

    Krambrich, D.

    2007-01-15

    Since spring 2004 the Crystal Ball Detector has been used for coincidence experiments probing the structure of the nucleons with real photons at the Mainzer Microtron. A major part of the commissioning, which was the first goal of this work, was the development and implementation of a new system for the Crystal Ball electronics. Components were designed or tested and, if necessary, modified to fit the experimental needs. After the commissioning, the set-up was then used successfully in several pion and eta production experiments for more than 2500 hours of beamtime. The second focus of this dissertation is the first measurement of the beam helicity asymmetry I{sup s}un in photoproduction of two neutral pions. The understanding of the excitation spectra of the nucleon requires experiments using polarised photons and/or polarised targets. Models based on different assumptions do reproduce the quantities measured without polarisation equally well but differ in the prediction of polarisation observables. The determination of more sensitive quantities is therefore mandatory. In contrast to single meson production, an observable appears in double pion production when using circularly polarized photons incident on an unpolarized target. This observable was determined as a function of energy and angle in the reactions {gamma} p {yields} p {pi}{sup 0} {pi}{sup 0} and in {gamma} p {yields} p {pi}{sup +} {pi}{sup -}. The results differ significantly from the model predictions. (orig.)

  8. Multiple-octave spanning high-energy mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    DEFF Research Database (Denmark)

    Zhou, Binbin; Bache, Morten

    2016-01-01

    supercontinuum generation in the visible, near-IR, and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal is pumped in the mid-IR. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second......-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed. The results were recorded in a commercially available crystal LiInS2 pumped in the 3-4 µm...

  9. Nsbnd H⋯O hydrogen bonded novel nonlinear optical semiorganic crystal (4-methoxyanilinium trifluoroacetate) studied through theoretical and experimental methods

    Science.gov (United States)

    Siva, V.; Suresh Kumar, S.; Suresh, M.; Raja, M.; Athimoolam, S.; Asath Bahadur, S.

    2017-04-01

    The new semi-organic crystal of 4-methoxyanilinium trifluoroacetate (4MATFA) was designed through strong Nsbnd H⋯O hydrogen bonds in the perspective of its nonlinear optical (NLO) properties. The crystalline state of 4MATFA was successfully attained by slow evaporation solution growth method at room temperature. The molecular structure of the grown crystal was determined by single crystal X-ray diffraction technique which confirms the importance of Nsbnd H⋯O hydrogen bonds in the molecular assembly. The amino group of the cation and carboxylate group of the anion are hydrogen bonded through two primary chains C12(4) and C22(6) motifs and a secondary ring R44(12) motif leading to alternate hydrophobic and hydrophilic layers at z = 0 or 1 and at z = 1/2, respectively. The molecular geometry was optimized theoretically by Hartree-Fock (HF) and Density Functional Theory (DFT) methods with 6-311++G(d,p) basis set. The optimized molecular geometrical parameters and computed vibrational spectra demonstrated the presence of Nsbnd H⋯O hydrogen bonds and the absence of expected Nsbnd H⋯F hydrogen bonds. The strong Nsbnd H⋯O tendency between the ions are observed as strong intensity isolated peak in computed IR spectra and strong intensity broad peak in experimental IR spectrum. Further, the calculated first (β) and second order hyperpolarizability (γ) values showed that the compound is good candidate for NLO applications. The chemical hardness, electro-negativity and chemical potential of the molecule were computed by HOMO - LUMO plot. The frontier orbital has lower band gap value, which indicate the possible optical activity of the molecule. The thermal stability of the grown crystals were confirmed by TG/DTA which showed the thermal stability of the compound upto 150 °C.

  10. The energy coupling efficiency of multi-wavelength laser pulses to damage initiating defects in DKDP nonlinear crystals

    Energy Technology Data Exchange (ETDEWEB)

    DeMange, P; Negres, R A; Rubenchik, A M; Radousky, H B; Feit, M D; Demos, S G

    2007-09-25

    The bulk damage performance of potassium dihydrogen phosphate crystals under simultaneous exposure to 1064-, 532-, and 355-nm nanosecond-laser pulses is investigated in order to probe the laser-induced defect reactions leading to damage initiation during frequency conversion. The results provide insight into the mechanisms governing the behavior of the damage initiating defects under exposure to high power laser light. In addition, it is suggested that the damage performance can be directly related to and predicted from the damage behavior of the crystal at each wavelength separately.

  11. Generation of microwave radiation by nonlinear interaction of a high-power, high-repetition rate, 1064-nm laser in KTP crystals

    CERN Document Server

    Borghesani, A F; Carugno, G

    2013-01-01

    We report measurements of microwave (RF) generation in the centimeter band accomplished by irradiating a nonlinear KTiOPO$_4$ (KTP) crystal with a home-made, infrared laser at $1064\\,$nm as a result of optical rectification (OR). The laser delivers pulse trains of duration up to $1\\,\\mu$s. Each train consists of several high-intensity pulses at an adjustable repetition rate of approximately $ 4.6\\,$GHz. The duration of the generated RF pulses is determined by that of the pulse trains. We have investigated both microwave- and second harmonic (SHG) generation as a function of the laser intensity and of the orientation of the laser polarization with respect to the crystallographic axes of KTP.

  12. All-Optical 1-to-8 Wavelength Multicasting at 20 Gbit/s Exploiting Self-Phase Modulation in Dispersion Flattened Highly Nonlinear Photonic Crystal Fiber

    Directory of Open Access Journals (Sweden)

    Zhan-Qiang Hui

    2014-01-01

    Full Text Available All-optical multicasting of performing data routing from single node to multiple destinations in the optical domain is promising for next generation ultrahigh-peed photonic networks. Based on the self-phase modulation in dispersion flattened highly nonlinear photonic crystal fiber and followed spectral filtering, simultaneous 1-to-8 all-optical wavelength multicasting return-to-zero (RZ signal at 20 Gbit/s with 100 GHz channel spaced is achieved. Wavelength tunable range and dynamic characteristic of proposed wavelength multicasting scheme is further investigated. The results show our designed scheme achieve operation wavelength range of 25 nm, OSNR of 32.01 dB and Q factor of 12.8. Moreover, the scheme has simple structure as well as high tolerance to signal power fluctuation.

  13. Simultaneous multi-channel CMW-band and MMW-band UWB monocycle pulse generation using FWM effect in a highly nonlinear photonic crystal fiber.

    Science.gov (United States)

    Zhang, Fangzheng; Wu, Jian; Fu, Songnian; Xu, Kun; Li, Yan; Hong, Xiaobin; Shum, Ping; Lin, Jintong

    2010-07-19

    We propose and experimentally demonstrate a scheme to simultaneously realize multi-channel centimeter wave (CMW) band and millimeter wave (MMW) band ultra-wideband (UWB) monocycle pulse generation using four wave mixing (FWM) effect in a highly nonlinear photonic crystal fiber (HNL-PCF). Two lightwaves carrying polarity-reversed optical Gaussian pulses with appropriate time delay and another lightwave carrying a 20 GHz clock signal are launched into the HNL-PCF together. By filtering out the FWM idlers, two CMW-band UWB monocycle signals and two MMW-band UWB monocycle signals at 20 GHz are obtained simultaneously. Experimental measurements of the generated UWB monocycle pulses at individual wavelength, which comply with the FCC regulations, verify the feasibility and flexibility of proposed scheme for use in practical UWB communication systems.

  14. Near Infrared (NIR) Imaging Techniques Using Lasers and Nonlinear Crystal Optical Parametric Oscillator/Amplifier (OPO/OPA) Imaging and Transferred Electron (TE) Photocathode Image Intensifiers

    Energy Technology Data Exchange (ETDEWEB)

    YATES,GEORGE J.; MCDONALD,THOMAS E. JR.; BLISS,DAVID E.; CAMERON,STEWART M.; GREIVES,KENNETH H.; ZUTAVERN,FRED J.

    2000-12-20

    Laboratory experiments utilizing different near-infrared (NIR) sensitive imaging techniques for LADAR range gated imaging at eye-safe wavelengths are presented. An OPO/OPA configuration incorporating a nonlinear crystal for wavelength conversion of 1.56 micron probe or broadcast laser light to 807 nm light by utilizing a second pump laser at 532 nm for gating and gain, was evaluated for sensitivity, resolution, and general image quality. These data are presented with similar test results obtained from an image intensifier based upon a transferred electron (TE) photocathode with high quantum efficiency (QE) in the 1-2 micron range, with a P-20 phosphor output screen. Data presented include range-gated imaging performance in a cloud chamber with varying optical attenuation of laser reflectance images.

  15. Air-guided photonic-crystal-fiber pulse-compression delivery of multimegawatt femtosecond laser output for nonlinear-optical imaging and neurosurgery

    Science.gov (United States)

    Lanin, Aleksandr A.; Fedotov, Il'ya V.; Sidorov-Biryukov, Dmitrii A.; Doronina-Amitonova, Lyubov V.; Ivashkina, Olga I.; Zots, Marina A.; Sun, Chi-Kuang; Ömer Ilday, F.; Fedotov, Andrei B.; Anokhin, Konstantin V.; Zheltikov, Aleksei M.

    2012-03-01

    Large-core hollow photonic-crystal fibers (PCFs) are shown to enable a fiber-format air-guided delivery of ultrashort infrared laser pulses for neurosurgery and nonlinear-optical imaging. With an appropriate dispersion precompensation, an anomalously dispersive 15-μm-core hollow PCF compresses 510-fs, 1070-nm light pulses to a pulse width of about 110 fs, providing a peak power in excess of 5 MW. The compressed PCF output is employed to induce a local photodisruption of corpus callosum tissues in mouse brain and is used to generate the third harmonic in brain tissues, which is captured by the PCF and delivered to a detector through the PCF cladding.

  16. Measurement of beam asymmetries in the reaction {gamma}p {yields} p{pi}{sup 0}{eta} with the Crystal Barrel/TAPS experiment at ELSA

    Energy Technology Data Exchange (ETDEWEB)

    Gutz, Eric Paul-Maria

    2011-07-01

    The photoproduction of mesons off the nucleon provides an excellent tool to gain further insight into the structure of baryons and their excitation spectrum. A large number of final states yielding various resonance contributions are accessible in photoproduction experiments. Especially in the regime of high-lying resonances, the photoproduction of multi-meson final states is of increasing importance, giving access to sequential decays of such resonances via e.g. {delta}(1232)P{sub 33} or N(1535)S{sub 11} in the intermediate state. For a complete understanding of the processes involved, however, it is insufficient to measure only unpolarized total and differential cross sections. The extraction of polarization observables from data obtained using polarized beams and targets is mandatory to constrain theoretical models and analyses and to uniquely determine the amplitudes participating in a given process. This work presents the analysis of data taken with the Crystal-Barrel/TAPS experiment at the accelerator facility ELSA in Bonn, using a linearly polarized photon beam impinging on a liquid hydrogen target. The detector system is optimized for the detection of multi-photon final states. The data has been selected for the reaction {gamma}p {yields} p{pi}{sup 0}{eta} {yields} p4{gamma} for an incoming photon energy range of 970 MeV to 1650 MeV. In this range, photon polarizations of up to 50% have been achieved. From this data, all polarization observables accessible with a linearly polarized photon beam and an unpolarized target have been extracted. This includes the beam asymmetry sum, determined as a function of various invariant masses and angles using a quasi two-body approach, along with the three-body asymmetries I{sup c} and I{sup s}. The latter two observables are unique to the acoplanar kinematics of multi-meson final states and have been measured for the first time within this work. The comparison of the results to solutions derived from various theoretical

  17. Doping effect of L-cystine on structural, UV-visible, SHG efficiency, third order nonlinear optical, laser damage threshold and surface properties of cadmium thiourea acetate single crystal

    Science.gov (United States)

    Azhar, S. M.; Anis, Mohd; Hussaini, S. S.; Kalainathan, S.; Shirsat, M. D.; Rabbani, G.

    2017-01-01

    The present article is focused to investigate the influence of L-cystine (LC) on linear-non-linear optical and laser damage threshold of cadmium thiourea acetate (CTA) crystal. The structural parameters of pure and LC doped CTA crystals have been determined using the single crystal X-ray diffraction technique. The functional groups of grown crystals have been identified by means of fourier transform infrared (FT-IR) analysis. The UV-visible spectral analysis has been done in the range of 200-900 nm to ascertain the uplifting influence of LC on optical properties of CTA crystal. The second harmonic generation (SHG) efficiency of LC doped CTA crystal is found to be higher than CTA and KDP crystal. The Z-scan technique has been employed to determine the third order nonlinear optical (TONLO) nature of LC doped CTA crystal at 632.8 nm. The self focusing tendency confirmed the strong kerr lensing ability of LC doped CTA crystal. The TONLO susceptibility (χ3), refraction (n2) and absorption coefficient (β) has been calculated using the Z-scan data. The laser damage threshold of pure and LC doped CTA crystals has been measured using the Q-switched Nd:YAG laser and its is found to be in range of GW/cm2. The surface analysis has been done by means of etching studies.

  18. Estimation of Joule heating and its role in nonlinear electrical response of Tb0.5Sr0.5MnO3 single crystal

    Science.gov (United States)

    Nhalil, Hariharan; Elizabeth, Suja

    2016-12-01

    Highly non-linear I-V characteristics and apparent colossal electro-resistance were observed in non-charge ordered manganite Tb0.5Sr0.5MnO3 single crystal in low temperature transport measurements. Significant changes were noticed in top surface temperature of the sample as compared to its base while passing current at low temperature. By analyzing these variations, we realize that the change in surface temperature (ΔTsur) is too small to have caused by the strong negative differential resistance. A more accurate estimation of change in the sample temperature was made by back-calculating the sample temperature from the temperature variation of resistance (R-T) data (ΔTcal), which was found to be higher than ΔTsur. This result indicates that there are large thermal gradients across the sample. The experimentally derived ΔTcal is validated with the help of a simple theoretical model and estimation of Joule heating. Pulse measurements realize substantial reduction in Joule heating. With decrease in sample thickness, Joule heating effect is found to be reduced. Our studies reveal that Joule heating plays a major role in the nonlinear electrical response of Tb0.5Sr0.5MnO3. By careful management of the duty cycle and pulse current I-V measurements, Joule heating can be mitigated to a large extent.

  19. Deep-ultraviolet second-harmonic generation by combined degenerate four-wave mixing and surface nonlinearity polarization in photonic crystal fiber.

    Science.gov (United States)

    Yuan, Jinhui; Kang, Zhe; Li, Feng; Zhou, Guiyao; Zhang, Xianting; Mei, Chao; Sang, Xinzhu; Wu, Qiang; Yan, Binbin; Zhou, Xian; Zhong, Kangping; Wang, Kuiru; Yu, Chongxiu; Lu, Chao; Tam, Hwa Yaw; Wai, P K A

    2017-08-23

    Deep-ultraviolet (UV) second-harmonics (SHs) have important applications in basic physics and applied sciences. However, it still remains challenging to generate deep-UV SHs especially in optical fibers. Here, for the first time, we experimentally demonstrate the deep-UV SH generations (SHGs) by combined degenerate four-wave mixing (FWM) and surface nonlinearity polarization in an in-house designed and fabricated air-silica photonic crystal fiber (PCF). When femtosecond pump pulses with average input power P av of 650 mW and center wavelength λ p of 810, 820, 830, and 840 nm are coupled into the normal dispersion region close to the zero-dispersion wavelength of the fundamental mode of the PCF, the anti-Stokes waves induced by degenerate FWM process are tunable from 669 to 612 nm. Then, they serve as the secondary pump, and deep-UV SHs are generated within the wavelength range of 334.5 to 306 nm as a result of surface nonlinearity polarization at the core-cladding interface of the PCF. The physical mechanism of the SHGs is confirmed by studying the dependences of the output power P SH of the SHs on the PCF length and time. Finally, we also establish a theoretical model to analyze the SHGs.

  20. Nonlinear polarization rotation in a dispersion-flattened photonic-crystal fiber for ultrawideband (> 100 nm) all-optical wavelength conversion of 10 Gbit/s nonreturn-to-zero signals

    DEFF Research Database (Denmark)

    Kwok, C.H.; Chow, C.W.; Tsang, H.K.;

    2006-01-01

    We study the conversion bandwidth of the cross-polarization-modulation (YPoIM)-based wavelength conversion scheme with a dispersion-flattened highly nonlinear photonic-crystal fiber for signals with a nonreturn-to-zero (NRZ) modulation format. Both theoretical and experimental results show...... using the YPoIM approach compared with the four-wave mixing approach previously reported is demonstrated....

  1. Studies on synthesis, structural, luminescent and thermal properties of a new non-linear optical crystal: 4-amino-4H-1,2,4-triazol-1-ium-3-hydroxy-2,4,6-trinitrophenolate

    Science.gov (United States)

    Dhamodharan, P.; Sathya, K.; Dhandapani, M.

    2017-03-01

    A new organic proton transfer complex having NLO activity, 4-amino-4H-1,2,4-triazol-1-ium-3-hydroxy-2,4,6-trinitrophenolate (ATHTP), was crystallized to investigate the factors which stabilize the structure of the crystal. The compound crystallizes in triclinic system with space group P-1. Elemental analysis, thermal analysis, UV-Vis-NIR, FT-IR and NMR spectral analyses were carried out to characterize the crystal. Optical, spectral and thermal properties of the title crystal were analyzed to recommend the material for optical applications. Z-scan was used to measure the effective third-order nonlinear optical susceptibility and nonlinear refractive index. The crystal structure was determined using single crystal XRD method and the structure was optimized using Gaussian 09 program at B3LYP/6-311++G(d,p) level of basis set. This hydrogen bond interactions led to the increase in first-order hyperpolarizability of ATHTP and was 30 times greater than that of urea. Hirshfeld analyses surface analysis was carried out to explore intermolecular interactions in the crystalline state.

  2. The linear and nonlinear response of infinite periodic systems to static and/or dynamic electric fields. Implementation in CRYSTAL code

    Science.gov (United States)

    Kirtman, Bernard; Springborg, Michael; Rérat, Michel; Ferrero, Mauro; Lacivita, Valentina; Orlando, Roberto; Dovesi, Roberto

    2015-01-01

    An implementation of the vector potential approach (VPA) for treating the response of infinite periodic systems to static and dynamic electric fields has been initiated within the CRYSTAL code. The VPA method is based on the solution of a time-dependent Hartree-Fock or Kohn-Sham equation for the crystal orbitals wherein the usual scalar potential, that describes interaction with the field, is replaced by the vector potential. This equation may be solved either by perturbation theory or by finite field methods. With some modification all the computational procedures of molecular ab initio quantum chemistry can be adapted for periodic systems. Accessible properties include the linear and nonlinear responses of both the nuclei and the electrons. The programming of static field pure electronic (hyper)polarizabilities has been successfully tested. Dynamic electronic (hyper)polarizabilities, as well as infrared and Raman intensities, are in progress while the addition of finite fields for calculation of vibrational (hyper)polarizabilities, through nuclear relaxation procedures, will begin shortly.

  3. Synthesis, crystal structure, spectroscopic characterization and nonlinear optical properties of manganese (II) complex of picolinate: A combined experimental and computational study

    Science.gov (United States)

    Tamer, Ömer; Avcı, Davut; Atalay, Yusuf; Çoşut, Bünyemin; Zorlu, Yunus; Erkovan, Mustafa; Yerli, Yusuf

    2016-02-01

    A novel manganese (II) complex with picolinic acid (pyridine 2-carboxylic acid, Hpic), namely, [Mn(pic)2(H2O)2] was prepared and its crystal structure was fully characterized by using single crystal X-ray diffraction. Picolinate (pic) ligands were coordinated to the central manganese(II) ion as bidentate N,O-donors through the nitrogen atoms of pyridine rings and the oxygen atoms of carboxylate groups forming five-membered chelate rings. The spectroscopic characterization of Mn(II) complex was performed by the applications of FT-IR, Raman, UV-vis and EPR techniques. In order to support these studies, density functional theory (DFT) calculations were carried out by using B3LYP level. IR and Raman spectra were simulated at B3LYP level, and obtained results indicated that DFT calculations generally give compatible results to the experimental ones. The electronic structure of the Mn(II) complex was predicted using time dependent DFT (TD-DFT) method with polarizable continuum model (PCM). Molecular stability, hyperconjugative interactions, intramolecular charge transfer (ICT) and bond strength were investigated by applying natural bond orbital (NBO) analysis. Nonlinear optical properties of Mn(II) complex were investigated by the determining of molecular polarizability (α) and hyperpolarizability (β) parameters.

  4. Highly nonlinear fundamental mechanisms of excitation and coloring of wide-gap crystals by intense femtosecond laser pulses

    Science.gov (United States)

    Martynovich, E. F.; Glazunov, D. S.; Grigorova, A. A.; Starchenko, A. A.; Kirpichnikov, A. V.; Trunov, V. I.; Merzlyakov, M. A.; Petrov, V. V.; Pestryakov, E. V.

    2008-09-01

    Analysis of the spatial distribution of the color centers formed in wide-gap LiF and MgF2 crystals in a laser beam channel has shown that these centers are formed in numerous longitudinal filaments into which a laser beam splits when propagating in a medium. The luminescence of the produced color centers is photoluminescence, which is excited by the supercontinuum radiation in the filaments.

  5. An Alternative Three-Term Decomposition for Single Crystal Deformation Motivated by Non-Linear Elastic Dislocation Solutions

    Science.gov (United States)

    2014-04-01

    irreversible deformation, the three-term model allows for residual elastic strains— including dilatation observed in experiments and atomic simulations...residual elastic strains—including dilatation observed in experiments and atomic simulations—not addressed by conventional two-term crystal plasticity...gradient for an element of crystalline material. For simplicity, thermal effects are omitted, gliding dislocations are the only kind of defect considered

  6. Crystal growth, vibrational, optical, thermal and theoretical studies of a nonlinear optical material: 2-Methyl 3,5-dinitrobenzoic acid

    Energy Technology Data Exchange (ETDEWEB)

    Sangeetha, K. [Department of Physics, Sri Sarada College for Women, Salem-16 (India); Guru Prasad, L. [Department of Science & Humanities, M. Kumarasamy College of Engineering, Karur (India); Mathammal, R. [Department of Physics, Sri Sarada College for Women, Salem-16 (India)

    2016-11-15

    Single crystals of 2-methyl 3,5-dinitro benzoic acid with reasonable size have been grown by slow evaporation solution growth method using ethanol as solvent. Quantum chemical calculation of 2-methyl 3,5-Dinitro benzoic acid was carried out by using DFT/B3LYP/6-31+G(d,p) method. The powder X-ray diffraction pattern was recorded and indexed. Both the experimental and theoretical vibrational spectrum validates the presence of functional groups. Polarizability, first order hyperpolarizability and the electric dipole moment values have been computed theoretically. The {sup 1}H and {sup 13}C NMR chemical shift of the molecule was calculated and compared with experimental results. TG/DSC analysis has been employed to understand the thermal and physio-chemical stability of the title compound. Frequency conversion property of the crystal was tested by Kurtz and Perry method. Optical absorption behavior of the grown crystal was examined by recording the optical spectrum and band gap energy was also estimated. The calculated HOMO and LUMO energy shows the charge transfer nature of the molecule.

  7. Crystal growth, vibrational, optical, thermal and theoretical studies of a nonlinear optical material: 2-Methyl 3,5-dinitrobenzoic acid

    Science.gov (United States)

    Sangeetha, K.; Guru Prasad, L.; Mathammal, R.

    2016-11-01

    Single crystals of 2-methyl 3,5-dinitro benzoic acid with reasonable size have been grown by slow evaporation solution growth method using ethanol as solvent. Quantum chemical calculation of 2-methyl 3,5-Dinitro benzoic acid was carried out by using DFT/B3LYP/6-31+G(d,p) method. The powder X-ray diffraction pattern was recorded and indexed. Both the experimental and theoretical vibrational spectrum validates the presence of functional groups. Polarizability, first order hyperpolarizability and the electric dipole moment values have been computed theoretically. The 1H and 13C NMR chemical shift of the molecule was calculated and compared with experimental results. TG/DSC analysis has been employed to understand the thermal and physio-chemical stability of the title compound. Frequency conversion property of the crystal was tested by Kurtz and Perry method. Optical absorption behavior of the grown crystal was examined by recording the optical spectrum and band gap energy was also estimated. The calculated HOMO and LUMO energy shows the charge transfer nature of the molecule.

  8. Studies on synthesis, structural, luminescent and thermal properties of a new non-linear optical crystal: 4-amino-4H-1,2,4-triazol-1-ium-3-hydroxy-2,4,6-trinitrophenolate

    Energy Technology Data Exchange (ETDEWEB)

    Dhamodharan, P.; Sathya, K.; Dhandapani, M., E-mail: chemistrydhandapani@gmail.com

    2017-03-01

    A new organic proton transfer complex having NLO activity, 4-amino-4H-1,2,4-triazol-1-ium-3-hydroxy-2,4,6-trinitrophenolate (ATHTP), was crystallized to investigate the factors which stabilize the structure of the crystal. The compound crystallizes in triclinic system with space group P-1. Elemental analysis, thermal analysis, UV–Vis–NIR, FT-IR and NMR spectral analyses were carried out to characterize the crystal. Optical, spectral and thermal properties of the title crystal were analyzed to recommend the material for optical applications. Z-scan was used to measure the effective third-order nonlinear optical susceptibility and nonlinear refractive index. The crystal structure was determined using single crystal XRD method and the structure was optimized using Gaussian 09 program at B3LYP/6-311++G(d,p) level of basis set. This hydrogen bond interactions led to the increase in first-order hyperpolarizability of ATHTP and was 30 times greater than that of urea. Hirshfeld analyses surface analysis was carried out to explore intermolecular interactions in the crystalline state. - Highlights: • Single crystals were grown by slow evaporation solution growth technique. • N-H…O, O-H…O and C-H…O type of interactions lead to stable network. • The thermal stability of the compound was investigated by TG/DTA analyses. • The third-order nonlinear optical susceptibility is found to be 2.1×10{sup −7} esu. • Hirshfeld analyses explore covalent and non covalent interactions.

  9. Linear and nonlinear transmission of Fe{sup 2+}-doped ZnSe crystals at a wavelength of 2940 nm in the temperature range 20–220 °C

    Energy Technology Data Exchange (ETDEWEB)

    Il' ichev, N N; Pashinin, P P; Gulyamova, E S; Bufetova, G A [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Shapkin, P V; Nasibov, A S [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2014-03-28

    The linear and nonlinear transmission of Fe{sup 2+}:ZnSe crystals is measured at a wavelength of 2940 nm in the temperature range 20 – 220 °C. It is found that, with increasing temperature from 20 °C to 150 – 220 °C, the transmission of Fe{sup 2+}:ZnSe crystals decreases in the case of incident radiation with an intensity of ∼5.5 MW cm{sup -2} and increases in the case of radiation with an intensity of 28 kW cm{sup -2}. At a temperature of 220 °C, the linear transmission almost coincides with the nonlinear transmission. The transmission spectra of Fe{sup 2+}:ZnSe crystals at temperatures of 22 and 220 °C in the wavelength range 500 – 7000 nm are presented. (active media)

  10. The density functional study of electronic structure, electronic charge density, linear and nonlinear optical properties of single crystal alpha-LiAlTe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A.H. [New Technologies-Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Khan, Wilayat, E-mail: walayat76@gmail.com [New Technologies-Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic)

    2014-04-01

    Highlights: • FP-LAPW technique is used for calculating the electronic structure. • The band structure shows that the calculated compound is semiconductor. • The complex dielectric function has been calculated. • Nonlinear optical properties has also been calculated. • This compound can be used for molecular engineering of the crystals. - Abstract: Self-consistent calculations is performed using the full potential linear augmented plane wave (FP-LAPW) technique based on density functional theory (DFT) to investigate the electronic band structure, density of states, electronic charge density, linear and non-linear optical properties of α-LiAlTe{sub 2} compound having tetragonal symmetry with space group I4{sup ¯}2d. The electronic structure are calculated using the Ceperley Alder local density approach (CA-LDA), Perdew Burke and Ernzerhof generalize gradient approach (PBE-GGA), Engel–Vosko generalize gradient approach (EVGGA) and modified Becke Johnson approach (mBJ). Band structure calculations of (α-LiAlTe{sub 2}) depict semiconducting nature with direct band gap of 2.35 eV (LDA), 2.48 eV (GGA), 3.05 eV (EVGGA) and 3.13 eV (mBJ), which is comparable to experimental value. The calculated electronic charge density show ionic interaction between Te and Li atoms and polar covalent interaction between Al and Te atoms. Some optical susceptibilities like dielectric constants, refractive index, extension co-efficient, reflectivity and energy loss function have been calculated and analyzed on the basis of electronic structure. The compound α-LiAlTe{sub 2} provides a considerable negative value of birefringence of −0.01. Any anisotropy observed in the linear optical properties which are in favor to enhance the nonlinear optical properties. The symbol χ{sub abc}{sup (2)}(ω) represents the second order nonlinear optical susceptibilities, possess six non-zero components in this symmetry (tetragonal), called: 1 2 3, 2 1 3, 2 3 1, 1 3 2, 3 1 2 and 3 2 1

  11. Strengthened nonlinearity in liquid crystal panel with ZnSe aligning layers due to surface charge accumulation

    Science.gov (United States)

    Zhao, Hua; Xue, Tingyu; Fu, Jiayin; Zhang, Jingwen

    2015-09-01

    With ZnSe thin films as aligning layers in fabricating liquid crystal (LC) panel with pentylcyanobiphenyl doped with C60, the response time in writing holograms was shortened to milliseconds. When two laser beams were overlapped in an LC panel, 2D diffraction patterns were observed, along with exponential gain coefficient highly LC and ZnSe thickness dependent. In addition, energy transferring in subwavelength scale through surface grating was evident. By using a hybrid LC panel, it was found the energy transferring direction was voltage polarity and thickness dependent. Electrostatic modification based surface plasmon polariton excitation was proposed to explain all the findings

  12. Polarization conversion in cubic Raman crystals

    Science.gov (United States)

    McKay, Aaron; Sabella, Alexander; Mildren, Richard P.

    2017-01-01

    Nonlinear conversion of unpolarized beams to lower frequencies is generally inefficient in c(2) materials, as it is challenging to achieve phase-matching for input ordinary and extraordinary beams simultaneously in the normal dispersion regime. Here, we show that cubic Raman crystals having doubly and triply degenerate (E and F type) modes provide a method for efficient nonlinear frequency downconversion of an unpolarized beam and yield a linearly polarized output state. Using Mueller calculus, optimal crystal directions for such polarization conversion are determined. Using diamond, an example of an F-class Raman crystal, we have verified that such conversion is possible with near quantum-defect-limited slope efficiency and a linear polarization contrast of more than 23.9 dB. PMID:28169327

  13. Investigation on the crystal growth, molecular structure and nonlinear optical susceptibilities of 2-[2-(4-Ethoxy-phenyl)-vinyl]-1-ethyl-stilbazolium iodide (EESI) by Z-scan technique using He-Ne laser for third-order nonlinear optical applications

    Science.gov (United States)

    Senthil, K.; Kalainathan, S.; Kondo, Y.; Hamada, F.; Yamada, M.

    2017-05-01

    Organic 2-[2-(4-Ethoxy-phenyl)-vinyl]-1-ethyl-stilbazolium iodide (EESI), a derivative of the stilbazolium family single crystal was synthesized by condensation method. Nearly perfect as-gown single crystals of EESI structure was confirmed by single-crystal X-ray diffraction studies. The crystal has a triclinic system with the space group P-1, the molecule consists of one pyridinium cation, one iodide anion, and 0·5H2O molecules. The nature of charge transfer, molecular properties, electrostatic potential map, and HOMO-LUMO energy gap of EESI have been theoretically investigated by Sparton'10 V1.0.1 program. The optical transparency of EESI was studied by Uv-Visible spectral analysis. The growth features were observed during the etching studies using a Carl Zeiss optical microscope (50X magnification). The mechanical behavior of the crystal was estimated by Vickers microhardness test, which shows reverse indentation size effect (RISE) with good mechanical stability. Both the dielectric constant and dielectric loss increases with the increasing temperature and attain almost constant at higher frequencies, which justify the crystal quality and essential parameter for electro-optic device applications. The complex impedance analysis explains the electrical property of EESI. TGA and DTA measurements determined the thermal stability of the grown crystal. Laser-induced damage threshold energy measurements exhibit that the excellent resistance with good threshold energy up to 2.08 GW/cm2 that was found to be more than that of some known organic and inorganic NLO crystals. Photoconductivity of EESI crystal confirms that the positive photoconductivity nature. Also, the third-order nonlinear optical (NLO) properties of EESI were investigated by using the single beam Z-scan technique under the Visible light (632.8 nm) region. The results show that EESI has effective third-order nonlinear optical property with the nonlinear refractive index n2 =1.787×10-11m2/W, third

  14. Plasmonic enhancement of second harmonic generation from nonlinear RbTiOPO4 crystals by aggregates of silver nanostructures

    DEFF Research Database (Denmark)

    Sánchez-García, Laura; Tserkezis, Christos; Ramírez, Mariola O

    2016-01-01

    We demonstrate a 60–fold enhancement of the second harmonic generation (SHG) response at the nanoscale in a hybrid metal-dielectric system. By using complex silver nanostructures photochemically deposited on the polar surface of a ferroelectric crystal, we tune the plasmonic resonances from...... the visible to the near-infrared (NIR) spectral region, matching either the SH or the fundamental frequency. In both cases the SHG signal at the metal-dielectric interface is enhanced, although with substantially different enhancement values: around 5 times when the plasmonic resonance is at the SH frequency...... or up to 60 times when it matches the fundamental NIR radiation. The results are consistent with the more spatially-extended near-field response of complex metallic nanostructures and can be well explained by taking into account the quadratic character of the SHG process. The work points out...

  15. Nonlinear phononics using atomically thin membranes

    Science.gov (United States)

    Midtvedt, Daniel; Isacsson, Andreas; Croy, Alexander

    2014-09-01

    Phononic crystals and acoustic metamaterials are used to tailor phonon and sound propagation properties by utilizing artificial, periodic structures. Analogous to photonic crystals, phononic band gaps can be created, which influence wave propagation and, more generally, allow engineering of the acoustic properties of a system. Beyond that, nonlinear phenomena in periodic structures have been extensively studied in photonic crystals and atomic Bose-Einstein condensates in optical lattices. However, creating nonlinear phononic crystals or nonlinear acoustic metamaterials remains challenging and only few examples have been demonstrated. Here, we show that atomically thin and periodically pinned membranes support coupled localized modes with nonlinear dynamics. The proposed system provides a platform for investigating nonlinear phononics.

  16. Growth of dopamine crystals

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Vidya, E-mail: vidya.patil@ruparel.edu; Patki, Mugdha, E-mail: mugdha.patki@ruparel.edu [D. G. Ruparel College, Senapati Bapat Marg, Mahim, Mumbai – 400 016 (India)

    2016-05-06

    Many nonlinear optical (NLO) crystals have been identified as potential candidates in optical and electro-optical devices. Use of NLO organic crystals is expected in photonic applications. Hence organic nonlinear optical materials have been intensely investigated due to their potentially high nonlinearities, and rapid response in electro-optic effect compared to inorganic NLO materials. There are many methods to grow organic crystals such as vapor growth method, melt growth method and solution growth method. Out of these methods, solution growth method is useful in providing constraint free crystal. Single crystals of Dopamine have been grown by evaporating the solvents from aqueous solution. Crystals obtained were of the size of orders of mm. The crystal structure of dopamine was determined using XRD technique. Images of crystals were obtained using FEG SEM Quanta Series under high vacuum and low KV.

  17. Growth of dopamine crystals

    Science.gov (United States)

    Patil, Vidya; Patki, Mugdha

    2016-05-01

    Many nonlinear optical (NLO) crystals have been identified as potential candidates in optical and electro-optical devices. Use of NLO organic crystals is expected in photonic applications. Hence organic nonlinear optical materials have been intensely investigated due to their potentially high nonlinearities, and rapid response in electro-optic effect compared to inorganic NLO materials. There are many methods to grow organic crystals such as vapor growth method, melt growth method and solution growth method. Out of these methods, solution growth method is useful in providing constraint free crystal. Single crystals of Dopamine have been grown by evaporating the solvents from aqueous solution. Crystals obtained were of the size of orders of mm. The crystal structure of dopamine was determined using XRD technique. Images of crystals were obtained using FEG SEM Quanta Series under high vacuum and low KV.

  18. Real-time terahertz wave imaging by nonlinear optical frequency up-conversion in a 4-dimethylamino-N'-methyl-4'-stilbazolium tosylate crystal

    Science.gov (United States)

    Fan, Shuzhen; Qi, Feng; Notake, Takashi; Nawata, Kouji; Matsukawa, Takeshi; Takida, Yuma; Minamide, Hiroaki

    2014-03-01

    Real-time terahertz (THz) wave imaging has wide applications in areas such as security, industry, biology, medicine, pharmacy, and arts. In this letter, we report on real-time room-temperature THz imaging by nonlinear optical frequency up-conversion in organic 4-dimethylamino-N'-methyl-4'-stilbazolium tosylate crystal. The active projection-imaging system consisted of (1) THz wave generation, (2) THz-near-infrared hybrid optics, (3) THz wave up-conversion, and (4) an InGaAs camera working at 60 frames per second. The pumping laser system consisted of two optical parametric oscillators pumped by a nano-second frequency-doubled Nd:YAG laser. THz-wave images of handmade samples at 19.3 THz were taken, and videos of a sample moving and a ruler stuck with a black polyethylene film moving were supplied online to show real-time ability. Thanks to the high speed and high responsivity of this technology, real-time THz imaging with a higher signal-to-noise ratio than a commercially available THz micro-bolometer camera was proven to be feasible. By changing the phase-matching condition, i.e., by changing the wavelength of the pumping laser, we suggest THz imaging with a narrow THz frequency band of interest in a wide range from approximately 2 to 30 THz is possible.

  19. Effect of field modulation on the quasi-phase-matching for second harmonic generation in a two-dimensional nonlinear photonic crystal

    Science.gov (United States)

    Zhao, Li-Ming; Zhou, Yun-Song; Wang, Ai-Hua

    2017-02-01

    Second harmonic generation (SHG) in a two-dimensional (2D) nonlinear photonic crystal (NPC) with finite width along z-direction that is embedded in air is investigated, without adopting the traditional approximations such as a plane-wave approximation (PWA) and slowly varying amplitude approximation (SVAA). The so-called quasi-phase-matching (QPM) and the corresponding SHG conversion efficiency can be modulated significantly by the field of fundamental wave (FW). It is assumed that the incident light, along z-direction, is normally launched upon the surface of the sample, and QPM for different directions is investigated. It is found that the QPM shows significant differences, compared with the traditional QPM along the two different directions: in the direction of finite width of the sample, the peak value of SHG conversion efficiency is deviated from the traditional case and it gets to its peak values when the transmittance resonance occurs. However, in the other direction, the deviation from the traditional QPM arises from the field modulation of the second harmonic wave (SHW) and in this direction, it is investigated that the full width at half maximum of QPM is much wider than that in the direction of finite width of the sample. These results can be used to provide a theoretical guidance for achieving QPM SHG.

  20. Determination of the Dalitz-plot parameter {alpha} for the decay {eta}{yields}3{pi}{sup 0} with the Crystal Ball at MAMI; Bestimmung des Dalitz-Plot-Parameters {alpha} fuer den Zerfall {eta} {yields} 3{pi}{sup 0} mit dem Crystal Ball am MAMI

    Energy Technology Data Exchange (ETDEWEB)

    Unverzagt, Marc

    2008-05-26

    In order to determine the Dalitz-plot parameter {alpha} experiments were evaluated, Which were performed with the Crystal Ball/TAPS facility at the accelerator MAMI of the Institute for Nuclear Physics at the Johannes Gutenberg University in Mainz in the years 2004 and 2005. {eta} mesons wer produced via the reaction {gamma}p{yields}{eta}p. From four different analyses the following four in this thesis determined Dalitz-plot parameters with the given statistics resulted: {eta} without proton: {alpha}=-0.0314{+-}0.0013{sub -0.0014}{sup +0.0017} (1.1.10{sup 6} events), {eta} with proton: {alpha}=-0.0338{+-}0.0020{sub -0.0022}{sup +0.0019} (4.2.10{sup 5} events), {delta}{sup +} magnetic dipole moment without proton: {alpha}=-0.0277{+-}0.0013{sub -0.0019}{sup +0.0014} (7.1.10{sup 5} events), {delta}{sup +} magnetic dipole moment with proton: {alpha}=-0.0272{+-}0.0019{sub -0.0043}{sup +0.0022} (3.1.10{sup 5} events).

  1. Nonlinear Cross Gramians

    Science.gov (United States)

    Ionescu, Tudor C.; Scherpen, Jacquelien M. A.

    We study the notion of cross Gramians for nonlinear gradient systems, using the characterization in terms of prolongation and gradient extension associated to the system. The cross Gramian is given for the variational system associated to the original nonlinear gradient system. We obtain linearization results that correspond to the notion of a cross Gramian for symmetric linear systems. Furthermore, first steps towards relations with the singular value functions of the nonlinear Hankel operator are studied and yield promising results.

  2. Using aeroelastic structures with nonlinear switching electronics to increase potential energy yield in airflow: investigating analog control circuitry for automated peak detection

    Science.gov (United States)

    Mihalca, Alexander G.; Drosinos, Jonathan G.; Grayson, Malika; Garcia, Ephrahim

    2015-03-01

    Bending piezoelectric transducers have the ability to harvest energy from aeroelastic vibrations induced by the ambient airflow. Such harvesters can have useful applications in the operation of low power devices, and their relatively small size makes them ideal for use in urban environments over civil infrastructure. One of the areas of focus regarding piezoelectric energy harvesting is the circuit topology used to store the harvested power. This study aims to further investigate the increase in potential energy yield from the piezoelectric harvester by optimizing the circuitry connecting the piezoelectric transducer and the power storage interface. When compared to an optimal resistive load case, it has been shown that certain circuit topologies, specifically synchronized switching and discharging to a storage capacitor through an inductor (SSDCI), can increase the charging power by as much as 400% if the circuit is completely lossless. This paper proposes a strategy for making a self-sufficient SSDCI circuit capable of peak detection for the synchronized switching using analog components. Using circuit simulation software, the performance of this proposed self-sufficient circuit is compared to an ideal case, and the effectiveness of the self-sufficient circuit strategy is discussed based on these simulation results. Further investigation of a physical working model of the new circuit proposal will be developed and experimental results of the circuit's performance obtained and compared to the estimated performance from the model.

  3. Studies on Growth, Spectral, Thermal, Mechanical and Optical Properties of 4-Bromoanilinium 4-Methylbenzenesulfonate Crystal: A Third Order Nonlinear Optical Material

    OpenAIRE

    Sivakumar,Pillukuruchi Kailasam; Kumar,Saravana; Kumar,Rangasamy Mohan; Kanagadurai,Ramajayam; Sagadevan,Suresh

    2016-01-01

    Abstract 4-Bromoanilinium 4-methylbenzenesulfonate (4BPTS) single crystal was successfully grown from ethanol by slow evaporation method at room temperature. The structure of grown crystal was confirmed by single crystal X-ray diffraction studies. The presence of functional groups of grown crystal was confirmed by the Fourier transform infrared spectroscopy (FTIR) spectral analysis. UV-Visible absorption study was performed on the grown crystal to determine the cut-off wavelength. The thermal...

  4. Spectroscopic and DFT-based computational studies on the molecular electronic structural characteristics and the third-order nonlinear property of an organic NLO crystal: (E)-N‧-(4-chlorobenzylidene)-4-methylbenzenesulfonohydrazide

    Science.gov (United States)

    Sasikala, V.; Sajan, D.; Joseph, Lynnette; Balaji, J.; Prabu, S.; Srinivasan, P.

    2017-04-01

    Single crystals of (E)-N‧-(4-chlorobenzylidene)-4-methylbenzenesulfonohydrazide (CBMBSH) have been grown by slow evaporation crystal growth method. The structure stabilizing intramolecular donor-acceptor interactions and the presence of the Nsbnd H⋯O, Csbnd H⋯O and Csbnd H⋯C(π) hydrogen bonds in the crystal were confirmed by vibrational spectroscopic and DFT methods. The linear optical absorption characteristics of the solvent phase of CBMBSH were investigated using UV-Vis-NIR spectroscopic and TD-DFT approaches. The 2PA assisted RSA nonlinear absorption and the optical limiting properties of CBMBSH were studied using the open-aperture Z-scan method. The topological characteristics of the electron density have been determined using the quantum theory of atoms in molecules method.

  5. Photonic crystal fibers for supercontinuum generation pumped by a gain-switched CW fiber laser

    DEFF Research Database (Denmark)

    Larsen, Casper; Noordegraaf, Danny; Hansen, Kim P.

    2012-01-01

    Supercontinuum generation in photonics crystal fibers (PCFs) pumped by CW lasers yields high spectral power density and average power. However, such systems require very high pump power and long nonlinear fibers. By on/off modulating the pump diodes of the fiber laser, the relaxation oscillations...

  6. Comments on the paper: 'Optical reflectance, optical refractive index and optical conductivity measurements of nonlinear optics for L-aspartic acid nickel chloride single crystal'

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R.; Naik, Suvidha G.; Dhavskar, Kiran T.

    2016-02-01

    We argue that the 'L-aspartic acid nickel chloride' crystal reported by the authors of the title paper (Optics Communications, 291 (2013) 304-308) is actually the well-known diaqua(L-aspartato)nickel(II) hydrate crystal.

  7. Optical reflectance, optical refractive index and optical conductivity measurements of nonlinear optics for L-aspartic acid nickel chloride single crystal

    Science.gov (United States)

    Anbazhagan, G.; Joseph, P. S.; Shankar, G.

    2013-03-01

    Single crystals of L-aspartic acid nickel chloride (LANC) were grown by the slow evaporation technique at room temperature. The grown crystals were subjected to Powder X-ray diffraction studies to confirm the crystal structure. The modes of vibration of different molecular groups present in LANC have been identified by FTIR spectral analysis. Optical transferency of the grown crystal was investigated by UV-Vis-NIR spectrum. The lower optical cut off wavelength for this crystal is observed at 240 nm and energy band gap 5.179 eV. The optical reflectance and optical refractive index studies have been carried out in this crystal. Finally, the optical conductivity and electrical conductivity studies have been carried out on LANC single crystal.

  8. A strategic approach to physico-chemical analysis of bis (thiourea) lead chloride - A reliable semi-organic nonlinear optical crystal

    Science.gov (United States)

    Rajagopalan, N. R.; Krishnamoorthy, P.; Jayamoorthy, K.

    2017-03-01

    Good quality crystals of bis thiourea lead chloride (BTLC) have been grown by slow evaporation method from aqueous solution. Orthorhombic structure and Pna21 space group of the crystals have been identified by single crystal X-ray diffraction. Studies on nucleation kinetics of grown BTLC has been carried out from which meta-stable zone width, induction period, free energy change, critical radius, critical number and growth rate have been calculated. The experimental values of interfacial surface energy for the crystal growth process have been compared with theoretical models. Ultra violet transmittance studies resulted in a high transmittance and wide band gap energy suggested the required optical transparency of the crystal. The second harmonic generation (SHG) and phase matching nature of the crystal have been justified by Kurtz-Perry method. The SHG nature of the crystal has been further attested by the higher values of theoretical hyper polarizability. The dielectric nature of the crystals at different temperatures with varying frequencies has been thoroughly studied. The activation energy values of the electrical process have been calculated from ac conductivity study. Solid state parameters including valence electron plasma energy, Penn gap, Fermi energy and polarisability have been unveiled by theoretical approach and correlated with the crystal's SHG efficiency. The values of hardness number, elastic stiffness constant, Meyer's Index, minimum level of indentation load, load dependent constant, fracture toughness, brittleness index and corrected hardness obtained from Vicker's hardness test clearly showed that the BTLC crystal has good mechanical stability required for NLO device fabrication.

  9. Optothermal nonlinearity of silica aerogel

    CERN Document Server

    Braidotti, Maria Chiara; Fleming, Adam; Samuels, Michiel C; Di Falco, Andrea; Conti, Claudio

    2016-01-01

    We report on the characterization of silica aerogel thermal optical nonlinearity, obtained by z-scan technique. The results show that typical silica aerogels have nonlinear optical coefficient similar to that of glass $(\\simeq 10^{-12} $m$^2/$W), with negligible optical nonlinear absorption. The non\\-li\\-near coefficient can be increased to values in the range of $10^{-10} $m$^2/$W by embedding an absorbing dye in the aerogel. This value is one order of magnitude higher than that observed in the pure dye and in typical highly nonlinear materials like liquid crystals.

  10. Modelling spreading dynamics of liquid crystals in three spatial dimensions

    CERN Document Server

    Lin, Te-Sheng; Thiele, Uwe; Cummings, Linda J

    2013-01-01

    We study spreading dynamics of nematic liquid crystal droplets within the framework of the long-wave approximation. A fourth order nonlinear parabolic partial differential equation governing the free surface evolution is derived. The influence of elastic distortion energy and of imposed anchoring variations at the substrate are explored through linear stability analysis and scaling arguments, which yield useful insight and predictions for the behaviour of spreading droplets. This behaviour is captured by fully nonlinear time-dependent simulations of three dimensional droplets spreading in the presence of anchoring variations that model simple defects in the nematic orientation at the substrate.

  11. Applications of nonlinear fiber optics

    CERN Document Server

    Agrawal, Govind

    2008-01-01

    * The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The bo

  12. Critical increase in Na-doping facilitates acceptor band movements that yields ~180 meV shallow hole conduction in ZnO bulk crystals

    Science.gov (United States)

    Parmar, Narendra S.; Yim, Haena; Choi, Ji-Won

    2017-03-01

    Stable p-type conduction in ZnO has been a long time obstacle in utilizing its full potential such as in opto-electronic devices. We designed a unique experimental set-up in the laboratory for high Na-doping by thermal diffusion in the bulk ZnO single crystals. SIMS measurement shows that Na concentration increases by 3 orders of magnitude, to ~3 × 1020 cm‑3 as doping temperature increases to 1200 °C. Electronic infrared absorption was measured for Na-acceptors. Absorption bands were observed near (0.20–0.24) eV. Absorption bands blue shifted by 0.04 eV when doped at 1200 °C giving rise to shallow acceptor level. NaZn band movements as a function of doping temperature are also seen in Photoluminescence emission (PL), Photoluminescence excitation (PLE) and UV-Vis transmission measurements. Variable temperature Hall measurements show stable p-type conduction with hole binding energy ~0.18 eV in ZnO samples that were Na-doped at 1200 °C.

  13. HIGH-PRESSURE RAMAN STUDY OF NON-LINEAR OPTICAL CRYSTALS%非线性光学晶体的高压拉曼散射研究

    Institute of Scientific and Technical Information of China (English)

    申泽骧

    2000-01-01

    报道了高压下非线性光学晶体KNbO3(KN),KIO3(KI)和KTiOAsO4(KTA)的Raman散射研究结果,压力引起的Raman光谱非常丰富,在所有的样品中都观察到了压致相变.另外,在KN晶体中发现了非常强的压致振动耦合现象及高压非晶相.对于KTA,建立了Raman光谱变化与其倍频效率随压力提高之间的可能联系.在22GPa以上,KI晶体的基本组成集团可能由IO3变为IO6.%In this presentation,we report on the high-pressure Raman spectroscopic studies of some non-linear optical crystals,e.g.KNbO3(KN),KIO3(KI) and KTiOAsO4(KTA),which are important for both their practical applications and theoretical values.The effect of pressure on KN is extremely large and there exist a rich variety of pressure-induced changes.Mode softening is found for some of the characteristic Raman bands.Intensity transfer and frequency repelling have been observed in the 200cm-1 region as a result of strong coupling between two B1(TO)modes,whose frequencies have been brought closer under pressure.There are three new crystalline and an amorphous phases,and two of the phase transitions are of displacive type.Three first-order pressure-induced phase transitions are inferred for KTA.The first takes place at 3.2GPa,indicated by drastic spectral changes related to TiO6 octahedra.The second occurs at 7.5GPa involving both TiO6 and AsO4 groups.Several modes belonging to TiO6 also soften between 0~7.5GPa.The third phase transition occurs near 10GPa and the high-pressure phase should be of higher symmetry.Drastic spectral changes and phase transitions are observed for KI up to 32GPa.The first transition occurs at 5.0GPa characterised by major spectral changes of the ν1,ν2,and ν4 modes.The other transitions are found at 8.7,15 and 22GPa.The phase that is stable between 15~22GPa has a higher symmetry than the phases in the lower pressures.The IO3 pyramidal ions may have lost their identity and changed to IO6 octahedra above 22GPa.

  14. Overview of Violet and Deep-UV Nonlinear Optical Crystals in the Last Decade%紫外、深紫外非线性光学晶体探索十年回顾

    Institute of Scientific and Technical Information of China (English)

    陈创天

    2001-01-01

    The investigations on violet and deep-UV nonlinear optical crystals over the last decade,including successes and failures,are discussed in this paper.Successes include the discovery of KBBF crystal which produces the shortest second harmonic output (184.7nm),and KABO crystal which has been successfully grown to centimeter size and is a promising candidate for the fourth and fifth harmonic generation of Nd∶YAG laser light.However,we were surprised that the SBBO crystal which has good linear and nonlinear properties lacks structural completeness.As a result,the crystal cannot be used yet.Although we have spent about ten years on this field,the search for deep-UV nonlinear optical crystals is still not satisfactory.In the near future we will make greater efforts to improve the quality of the crystals we have discovered and will continue to search for the new ones that can overcome the problems of existing crystals.%本文讨论了近10年来我们研究组在探索紫外、深紫外非线性光学晶体方面的经历。这些经历中有成功的一面,也有不成功的一面。成功的一面包括KBBF晶体的发现及最短倍频波的输出(184.7nm),以及最近使用的一种特殊的器件设计,使KBBF晶体能够产生有效的深紫外谐波光输出;KABO晶体的发现及厘米级晶体的获得,有可能使此晶体在Nd∶YAG激光的4、5倍频器件中得到应用。而我们没有想到的是线性和非线性光学性能均很优秀的SBBO晶体,却发现结构的完整性有问题,目前还不能得到实际的应用,在今后仍需花很大的精力去研究它。最后,我们虽然已花了10年时间,但深紫外非线性光学晶体仍旧没有得到理想的解决,还需我们继续努力。由此可见,一个科学问题的认真解决,是需要花非常长的时间。本文希望把我们研究组的近10年来的经验写出来,供大家参考,以求共勉。

  15. Solitons in nonlinear lattices

    CERN Document Server

    Kartashov, Yaroslav V; Torner, Lluis

    2010-01-01

    This article offers a comprehensive survey of results obtained for solitons and complex nonlinear wave patterns supported by purely nonlinear lattices (NLs), which represent a spatially periodic modulation of the local strength and sign of the nonlinearity, and their combinations with linear lattices. A majority of the results obtained, thus far, in this field and reviewed in this article are theoretical. Nevertheless, relevant experimental settings are surveyed too, with emphasis on perspectives for implementation of the theoretical predictions in the experiment. Physical systems discussed in the review belong to the realms of nonlinear optics (including artificial optical media, such as photonic crystals, and plasmonics) and Bose-Einstein condensation (BEC). The solitons are considered in one, two, and three dimensions (1D, 2D, and 3D). Basic properties of the solitons presented in the review are their existence, stability, and mobility. Although the field is still far from completion, general conclusions c...

  16. Investigation of optical and electrical properties of L-Cystein doped zinc thiourea chloride (ZTC) crystal for nonlinear optical (NLO) applications

    Science.gov (United States)

    Anis, Mohd; Shaikh, R. N.; Shirsat, M. D.; Hussaini, S. S.

    2014-08-01

    The single crystal of L-Cystein doped zinc thiourea chloride (ZTC) has been grown by slow evaporation technique. The optical study revealed that the doped ZTC crystal has high transmission with lowest cut off wavelength of 306 nm. The optical band gap was found to be 4.2 eV. The transition band gaps were studied using the photoluminescence spectrum. The incorporation of L-Cystein in ZTC was estimated qualitatively by FT-IR analysis. The presence of dopant was confirmed by energy diffraction X-ray analysis (EDAX) analysis. The lower dielectric characteristics of doped ZTC crystal were scrutinized by dielectric measurements. The high thermal stability of grown crystal was ascertained by TG/DTA analysis. The Second harmonic generation (SHG) efficiency measured using Nd-YAG laser is 1.96 times that of pure ZTC.

  17. The physics of quadrupole interactions in crystals. Quadrupole interactions observed in the 1{sup +} {yields} 0{sup +}{gamma}-ray transition

    Energy Technology Data Exchange (ETDEWEB)

    Goldting, G. [Weizmann Inst. of Science, Rehovoth (Israel); Anderssen, S.S.; Lane, G.J. [Australian National Univ., Canberra, ACT (Australia). Research School of Physical Sciences

    1995-11-01

    For many people the nuclear interaction with the electric quadrupole is not as easily understood as the magnetic dipole interaction. This is partly due to the use of Racah algebra in conventional quadrupole interaction calculations. Although this is a powerful technique that provides a neat summation over the m-substates of both the initial nuclear state and the emitted radiation, the formalism does tend to `hide` some of the details and interesting features of the interaction. Therefore, to improve our understanding of these processes with an emphasis on the physical characteristics, these notes will detail the calculation of quadrupole interactions with both polarised and aligned nuclei without using Racah algebra. To make these calculations manageable only the 1{sup +}{yields} 0{sup +}{gamma}-ray transition is considered. The J{sup {pi}} =1{sup +} state has only 3 substates (m = -1,0,+1), and the parity and angular momentum selection rules allow only M1 magnetic dipole transitions. The calculation has led to some explanations of the difference between the aligned and polarized quadrupole interactions, which is the orientation of the quantization axis with respect to the equatorial plane.

  18. Comment on the paper "Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-chloro 4-nitrostilbene (CONS): a potential NLO material" by P.M. Dinakaran, S. Kalainathan [Spectrochim. Acta A 111 (2013) 123-130].

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R; Dhuri, Sunder N; Nadkarni, V S

    2014-01-03

    We argue that (trans)-4-chloro-4'-nitrostilbene is not a new organic nonlinear optical material as claimed by Dinakaran and Kalainathan [P.M. Dinakaran, S. Kalainathan, Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-Chloro 4-Nitrostilbene (CONS): a potential NLO material, Spectrochim. Acta A 111 (2013) 123-130], but instead a well-known compound whose synthesis, spectral data, single crystal structure and second harmonic generation (SHG) efficiency are well documented in the literature. The title paper is completely erroneous. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. A comparative study on the growth and characterization of nonlinear optical amino acid crystals: L-alanine (LA) and L-alanine alaninium nitrate (LAAN).

    Science.gov (United States)

    Aravindan, A; Srinivasan, P; Vijayan, N; Gopalakrishnan, R; Ramasamy, P

    2008-11-15

    A comparative study on the properties of L-alanine and LAAN crystals has been made and discussed. It may be concluded that the protonation of the amino group in the L-alanine molecule is the key factor in increasing the relative SHG efficiency of LAAN. The protonation is justified by the crystal structure analysis, FTIR and photoluminescence studies. The factor group vibrations are compared and found that there is an increase in vibrational modes of LA when reacted with nitric acid forming LAAN.

  20. Nonlinear polarization rotation in a dispersion-flattened photonic-crystal fiber for ultrawideband (>100 nm) all-optical wavelength conversion of 10 Gbit/s nonreturn-to-zero signals.

    Science.gov (United States)

    Kwok, C H; Chow, C W; Tsang, H K; Lin, Chinlon; Bjarklev, A

    2006-06-15

    We study the conversion bandwidth of the cross-polarization-modulation (XPoIM)-based wavelength conversion scheme with a dispersion-flattened highly nonlinear photonic-crystal fiber for signals with a nonreturn-to-zero (NRZ) modulation format. Both theoretical and experimental results show that the conversion bandwidth can be extended to cover a very wide band, including S-, C-, and L-bands for 10 Gbit/s NRZ signals (a total bandwidth of 120 nm is experimentally demonstrated). We also study the theoretical bandwidth limit for 40 Gbit/s NRZ signals. A significant extension of the conversion bandwidth using the XPoIM approach compared with the four-wave mixing approach previously reported is demonstrated.