Nonlinear optical interactions in silicon waveguides
Kuyken, B.; Leo, F.; Clemmen, S.; Dave, U.; Van Laer, R.; Ideguchi, T.; Zhao, H.; Liu, X.; Safioui, J.; Coen, S.; Gorza, S. P.; Selvaraja, S. K.; Massar, S.; Osgood, R. M.; Verheyen, P.; Van Campenhout, J.; Baets, R.; Green, W. M. J.; Roelkens, G.
2017-03-01
The strong nonlinear response of silicon photonic nanowire waveguides allows for the integration of nonlinear optical functions on a chip. However, the detrimental nonlinear optical absorption in silicon at telecom wavelengths limits the efficiency of many such experiments. In this review, several approaches are proposed and demonstrated to overcome this fundamental issue. By using the proposed methods, we demonstrate amongst others supercontinuum generation, frequency comb generation, a parametric optical amplifier, and a parametric optical oscillator.
Nonlinear interaction of meta-atoms through optical coupling
Energy Technology Data Exchange (ETDEWEB)
Slobozhanyuk, A. P.; Kapitanova, P. V.; Filonov, D. S.; Belov, P. A. [National Research University of Information Technologies, Mechanics and Optics (ITMO), St. Petersburg 197101 (Russian Federation); Powell, D. A. [Nonlinear Physics Centre and Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Australian National University, Canberra, ACT 0200 (Australia); Shadrivov, I. V.; Kivshar, Yu. S. [National Research University of Information Technologies, Mechanics and Optics (ITMO), St. Petersburg 197101 (Russian Federation); Nonlinear Physics Centre and Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Australian National University, Canberra, ACT 0200 (Australia); Lapine, M., E-mail: mlapine@physics.usyd.edu.au [National Research University of Information Technologies, Mechanics and Optics (ITMO), St. Petersburg 197101 (Russian Federation); Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), School of Physics, University of Sydney, New South Wales 2006 (Australia); McPhedran, R. C. [Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), School of Physics, University of Sydney, New South Wales 2006 (Australia)
2014-01-06
We propose and experimentally demonstrate a multi-frequency nonlinear coupling mechanism between split-ring resonators. We engineer the coupling between two microwave resonators through optical interaction, whilst suppressing the direct electromagnetic coupling. This allows for a power-dependent interaction between the otherwise independent resonators, opening interesting opportunities to address applications in signal processing, filtering, directional coupling, and electromagnetic compatibility.
Contactless nonlinear optics mediated by long-range Rydberg interactions
Busche, Hannes; Huillery, Paul; Ball, Simon W.; Ilieva, Teodora; Jones, Matthew P. A.; Adams, Charles S.
2017-07-01
In conventional nonlinear optics, linear quantum optics, and cavity quantum electrodynamics to create effective photon-photon interactions photons must have, at one time, interacted with matter inside a common medium. In contrast, in Rydberg quantum optics, optical photons are coherently and reversibly mapped onto collective atomic Rydberg excitations, giving rise to dipole-mediated effective photon-photon interactions that are long range. Consequently, a spatial overlap between the light modes is no longer required. We demonstrate such a contactless coupling between photons stored as collective Rydberg excitations in spatially separate optical media. The potential induced by each photon modifies the retrieval mode of its neighbour, leading to correlations between them. We measure these correlations as a function of interaction strength, distance and storage time, demonstrating an effective interaction between photons separated by 15 times their wavelength. Contactless effective photon-photon interactions are relevant for scalable multichannel photonic devices and the study of strongly correlated many-body dynamics using light.
Quantum nonlinear optics with single photons enabled by strongly interacting atoms
DEFF Research Database (Denmark)
Peyronel, Thibault; Firstenberg, Ofer; Liang, Qi Yu
2012-01-01
The realization of strong nonlinear interactions between individual light quanta (photons) is a long-standing goal in optical science and engineering, being of both fundamental and technological significance. In conventional optical materials, the nonlinearity at light powers corresponding...
Chen, Xianfeng; Zeng, Heping; Guo, Qi; She, Weilong
2015-01-01
This book presents an overview of the state of the art of nonlinear optics from weak light nonlinear optics, ultrafast nonlinear optics to electro-optical theory and applications. Topics range from the fundamental studies of the interaction between matter and radiation to the development of devices, components, and systems of tremendous commercial interest for widespread applications in optical telecommunications, medicine, and biotechnology.
Bloembergen, Nicolaas
1996-01-01
Nicolaas Bloembergen, recipient of the Nobel Prize for Physics (1981), wrote Nonlinear Optics in 1964, when the field of nonlinear optics was only three years old. The available literature has since grown by at least three orders of magnitude.The vitality of Nonlinear Optics is evident from the still-growing number of scientists and engineers engaged in the study of new nonlinear phenomena and in the development of new nonlinear devices in the field of opto-electronics. This monograph should be helpful in providing a historical introduction and a general background of basic ideas both for expe
Boyd, Robert W
2013-01-01
Nonlinear Optics is an advanced textbook for courses dealing with nonlinear optics, quantum electronics, laser physics, contemporary and quantum optics, and electrooptics. Its pedagogical emphasis is on fundamentals rather than particular, transitory applications. As a result, this textbook will have lasting appeal to a wide audience of electrical engineering, physics, and optics students, as well as those in related fields such as materials science and chemistry.Key Features* The origin of optical nonlinearities, including dependence on the polarization of light* A detailed treatment of the q
Fardad, Shima; Mills, Matthew S; Zhang, Peng; Man, Weining; Chen, Zhigang; Christodoulides, D N
2013-09-15
We demonstrate optical interactions between stable self-trapped optical beams in soft-matter systems with pre-engineered saturable self-focusing optical nonlinearities. Our experiments, carried out in dilute suspensions of particles with negative polarizabilities, show that optical beam interactions can vary from attractive to repulsive, or can display an energy exchange depending on the initial relative phases. The corresponding observations are in good agreement with theoretical predictions.
Topological charge algebra of optical vortices in nonlinear interactions.
Zhdanova, Alexandra A; Shutova, Mariia; Bahari, Aysan; Zhi, Miaochan; Sokolov, Alexei V
2015-12-28
We investigate the transfer of orbital angular momentum among multiple beams involved in a coherent Raman interaction. We use a liquid crystal light modulator to shape pump and Stokes beams into optical vortices with various integer values of topological charge, and cross them in a Raman-active crystal to produce multiple Stokes and anti-Stokes sidebands. We measure the resultant vortex charges using a tilted-lens technique. We verify that in every case the generated beams' topological charges obey a simple relationship, resulting from angular momentum conservation for created and annihilated photons, or equivalently, from phase-matching considerations for multiple interacting beams.
Institute of Scientific and Technical Information of China (English)
YU You-Bin
2008-01-01
The electron-phonon interaction influences on linear and nonlinear optical absorption in cylindrical quantum wires (CQW) with an infinite confining potential are investigated. The optical absorption coefficients are obtained by using the compact-density-matrix approach and iterative method, and the numerical results are presented for GaAs CQW. The results show that the electron-phonon interaction makes a distinct influence on optical absorption in CQW. The electron-phonon interaction on the wave functions of electron dominates the values of absorption coefficients and the correction of the electron-phonon effect on the energies of the electron makes the absorption peaks blue shift and become wider. Moreover, the electron-phonon interaction influence on optical absorption with an infinite confining potential is different from that with a finite confining potential.
Leburn, Christopher; Reid, Derryck
2013-01-01
The field of ultrafast nonlinear optics is broad and multidisciplinary, and encompasses areas concerned with both the generation and measurement of ultrashort pulses of light, as well as those concerned with the applications of such pulses. Ultrashort pulses are extreme events – both in terms of their durations, and also the high peak powers which their short durations can facilitate. These extreme properties make them powerful experiment tools. On one hand, their ultrashort durations facilitate the probing and manipulation of matter on incredibly short timescales. On the other, their ultrashort durations can facilitate high peak powers which can drive highly nonlinear light-matter interaction processes. Ultrafast Nonlinear Optics covers a complete range of topics, both applied and fundamental in nature, within the area of ultrafast nonlinear optics. Chapters 1 to 4 are concerned with the generation and measurement of ultrashort pulses. Chapters 5 to 7 are concerned with fundamental applications of ultrasho...
Schmidt, Bruno E; Ernotte, Guilmot; Clerici, Matteo; Morandotti, Roberto; Ibrahim, Heide; Legare, Francois
2016-01-01
In the framework of linear optics, light fields do not interact with each other in a medium. Yet, when their field amplitude becomes comparable to the electron binding energies of matter, the nonlinear motion of these electrons emits new dipole radiation whose amplitude, frequency and phase differ from the incoming fields. Such high fields are typically achieved with ultra-short, femtosecond (1fs = 10-15 sec.) laser pulses containing very broad frequency spectra. Here, the matter not only couples incoming and outgoing fields but also causes different spectral components to interact and mix through a convolution process. In this contribution, we describe how frequency domain nonlinear optics overcomes the shortcomings arising from this convolution in conventional time domain nonlinear optics1. We generate light fields with previously inaccessible properties because the uncontrolled coupling of amplitudes and phases is turned off. For example, arbitrary phase functions are transferred linearly to the second har...
Energy Technology Data Exchange (ETDEWEB)
Kumar, Manoj [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Lahon, Siddhartha, E-mail: sid.lahon@gmail.com [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Department of Physics, Kirori Mal College, University of Delhi, Delhi 110007 (India); Jha, Pradip Kumar [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Department of Physics, DDU College, University of Delhi, Delhi 110007 (India); Gumber, Sukirti; Mohan, Man [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)
2014-04-01
Here we have investigated the influence of external electric field and magnetic field on the nonlinear optical rectification of a parabolic confinement wire in the presence of Rashba spin–orbit interaction. We have used density matrix formulation for obtaining optical properties within the effective mass approximation. The results are presented as a function of quantum wire radius, electric field, magnetic field, Rashba spin–orbit interaction strength and photon energy. Our results indicate an increase of electric field gives the red-shift of the peak positions of nonlinear optical rectification. The role of confinement strength and spin–orbit interaction strength as control parameters on this nonlinear property have been demonstrated.
Organic nonlinear optical materials
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.
Agrawal, Govind P
2001-01-01
The Optical Society of America (OSA) and SPIE - The International Society for Optical Engineering have awarded Govind Agrawal with an honorable mention for the Joseph W. Goodman Book Writing Award for his work on Nonlinear Fiber Optics, 3rd edition.Nonlinear Fiber Optics, 3rd Edition, provides a comprehensive and up-to-date account of the nonlinear phenomena occurring inside optical fibers. It retains most of the material that appeared in the first edition, with the exception of Chapter 6, which is now devoted to the polarization effects relevant for light propagation in optical
Lugiato, Luigi; Brambilla, Massimo
2015-01-01
Guiding graduate students and researchers through the complex world of laser physics and nonlinear optics, this book provides an in-depth exploration of the dynamics of lasers and other relevant optical systems, under the umbrella of a unitary spatio-temporal vision. Adopting a balanced approach, the book covers traditional as well as special topics in laser physics, quantum electronics and nonlinear optics, treating them from the viewpoint of nonlinear dynamical systems. These include laser emission, frequency generation, solitons, optically bistable systems, pulsations and chaos and optical pattern formation. It also provides a coherent and up-to-date treatment of the hierarchy of nonlinear optical models and of the rich variety of phenomena they describe, helping readers to understand the limits of validity of each model and the connections among the phenomena. It is ideal for graduate students and researchers in nonlinear optics, quantum electronics, laser physics and photonics.
Nonlinear optics principles and applications
Li, Chunfei
2017-01-01
This book reflects the latest advances in nonlinear optics. Besides the simple, strict mathematical deduction, it also discusses the experimental verification and possible future applications, such as the all-optical switches. It consistently uses the practical unit system throughout. It employs simple physical images, such as "light waves" and "photons" to systematically explain the main principles of nonlinear optical effects. It uses the first-order nonlinear wave equation in frequency domain under the condition of “slowly varying amplitude approximation" and the classical model of the interaction between the light and electric dipole. At the same time, it also uses the rate equations based on the energy-level transition of particle systems excited by photons and the energy and momentum conservation principles to explain the nonlinear optical phenomenon. The book is intended for researchers, engineers and graduate students in the field of the optics, optoelectronics, fiber communication, information tech...
Distributed nonlinear optical response
DEFF Research Database (Denmark)
Nikolov, Nikola Ivanov
2005-01-01
The purpose of the research presented here is to investigate basic physical properties in nonlinear optical materials with delayed or nonlocal nonlinearity. Soliton propagation, spectral broadening and the influence of the nonlocality or delay of the nonlinearity are the main focusses in the work...
Eaton, D F
1991-07-19
The current state of materials development in nonlinear optics is summarized, and the promise of these materials is critically evaluated. Properties and important materials constants of current commercial materials and of new, promising, inorganic and organic molecular and polymeric materials with potential in second- and third-order nonlinear optical applications are presented.
Nonlinear optics and photonics
He, Guang S
2015-01-01
This book provides a comprehensive presentation on most of the major topics in nonlinear optics and photonics, with equal emphasis on principles, experiments, techniques, and applications. It covers many major new topics including optical solitons, multi-photon effects, nonlinear photoelectric effects, fast and slow light , and Terahertz photonics. Chapters 1-10 present the fundamentals of modern nonlinear optics, and could be used as a textbook with problems provided at the end of each chapter. Chapters 11-17 cover the more advanced topics of techniques and applications of nonlinear optics and photonics, serving as a highly informative reference for researchers and experts working in related areas. There are also 16 pages of color photographs to illustrate the visual appearances of some typical nonlinear optical effects and phenomena. The book could be adopted as a textbook for both undergraduates and graduate students, and serve as a useful reference work for researchers and experts in the fields of physics...
Stolz, A; Markey, L; Francs, G Colas des; Bouhelier, A
2013-01-01
We introduce strongly-coupled optical gap antennas to interface optical radiation with current-carrying electrons at the nanoscale. The transducer relies on the nonlinear optical and electrical properties of an optical antenna operating in the tunneling regime. We discuss the underlying physical mechanisms controlling the conversion and demonstrate that a two-wire optical antenna can provide advanced optoelectronic functionalities beyond tailoring the electromagnetic response of a single emitter. Interfacing an electronic command layer with a nanoscale optical device may thus be facilitated by the optical rectennas discussed here.
Cross-polarized wave generation by effective cubic nonlinear optical interaction.
Petrov, G I; Albert, O; Etchepare, J; Saltiel, S M
2001-03-15
A new cubic nonlinear optical effect in which a linearly polarized wave propagating in a single quadratic medium is converted into a wave that is cross polarized to the input wave is observed in BBO crystal. The effect is explained by cascading of two different second-order processes: second-harmonic generation and difference frequency mixing.
Bentley, Sean J; Heebner, John E; Boyd, Robert W
2006-04-01
We describe observations of various transverse instabilities that occur when two laser beams intersect in nonlinear optical liquids. Patterns that we observe include two types of conical emission and the generation of a linear array of spots. These results can be understood in terms of the physical processes of self-diffraction, two-beam-excited conical emission, and seeded modulational instability.
Nonlinear effects in optical fibers
Ferreira, Mario F
2011-01-01
Cutting-edge coverage of nonlinear phenomena occurring inside optical fibers Nonlinear fiber optics is a specialized part of fiber optics dealing with optical nonlinearities and their applications. As fiber-optic communication systems have become more advanced and complex, the nonlinear effects in optical fibers have increased in importance, as they adversely affect system performance. Paradoxically, the same nonlinear phenomena also offer the promise of addressing the bandwidth bottleneck for signal processing for future ultra-high speed optical networks. Nonlinear Effects in Optical Fiber
Fundamentals of nonlinear optics
Powers, Peter E
2011-01-01
Peter Powers's rigorous but simple description of a difficult field keeps the reader's attention throughout. … All chapters contain a list of references and large numbers of practice examples to be worked through. … By carefully working through the proposed problems, students will develop a sound understanding of the fundamental principles and applications. … the book serves perfectly for an introductory-level course for second- and third-order nonlinear optical phenomena. The author's writing style is refreshing and original. I expect that Fundamentals of Nonlinear Optics will fast become pop
Nonlinear fibre optics overview
DEFF Research Database (Denmark)
Travers, J. C.; Frosz, Michael Henoch; Dudley, J. M.
2010-01-01
, provides a background to the associated nonlinear optical processes, treats the generation mechanisms from continuous wave to femtosecond pulse pump regimes and highlights the diverse applications. A full discussion of numerical methods and comprehensive computer code are also provided, enabling readers...
Energy Technology Data Exchange (ETDEWEB)
Max-Planck-Institut fur Quantenoptik; Goulielmakis, E.; Schultze, M.; Hofstetter, M.; Yakovlev, V. S.; Gagnon, J.; Uiberacker, M.; Aquila, A. L.; gullikson, E. M.; attwood, D. T.; Kienberger, R.; Krausz, F.; Kleineberg, U.
2008-11-05
Nonlinear optics plays a central role in the advancement of optical science and laser-based technologies. We report on the confinement of the nonlinear interaction of light with matter to a single wave cycle and demonstrate its utility for time-resolved and strong-field science. The electric field of 3.3-femtosecond, 0.72-micron laser pulses with a controlled and measured waveform ionizes atoms near the crests of the central wave cycle, with ionization being virtually switched off outside this interval. Isolated sub-100-attosecond pulses of extreme ultraviolet light (photon energy {approx} 80 electron volts), containing {approx} 0.5 nanojoule of energy, emerge from the interaction with a conversion efficiency of {approx} 10{sup -6}. These tools enable the study of the precision control of electron motion with light fields and electron-electron interactions with a resolution approaching the atomic unit of time ({approx} 24 attoseconds).
Handbook of nonlinear optical crystals
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
DEFF Research Database (Denmark)
Parigi, V.; Bimbard, E.; Stanojevic, J.
2012-01-01
We observe and measure dispersive optical nonlinearities in an ensemble of cold Rydberg atoms placed inside an optical cavity. The experimental results are in agreement with a simple model where the optical nonlinearities are due to the progressive appearance of a Rydberg blockaded volume within ...
Parigi, Valentina; Bimbard, Erwan; Stanojevic, Jovica; Hilliard, Andrew J; Nogrette, Florence; Tualle-Brouri, Rosa; Ourjoumtsev, Alexei; Grangier, Philippe
2012-12-07
We observe and measure dispersive optical nonlinearities in an ensemble of cold Rydberg atoms placed inside an optical cavity. The experimental results are in agreement with a simple model where the optical nonlinearities are due to the progressive appearance of a Rydberg blockaded volume within the medium. The measurements allow a direct estimation of the "blockaded fraction" of atoms within the atomic ensemble.
Energy Technology Data Exchange (ETDEWEB)
Hassanabadi, Hassan, E-mail: h.hasanabadi@shahroodut.ac.ir [Physics Department, Shahrood University of Technology, P.O. Box 3619995161-316, Shahrood (Iran, Islamic Republic of); Rahimov, Hamed [Physics Department, Shahrood University of Technology, P.O. Box 3619995161-316, Shahrood (Iran, Islamic Republic of); Lu Liangliang [Department of Physics, College of Physics and Electronic Engineering, Guangzhou University, Guangzhou 510006 (China); Wang Chao [Institute of Public Administration, Guangzhou University, Guangzhou 510006 (China)
2012-05-15
In this study, a detailed investigation of the nonlinear optical properties such as optical absorption and refractive index change associated with intersubband transitions in a three-electron quantum dot in two dimensions in the presence of the Rashba spin-orbit interaction has been carried out. We present the exact wave functions and energy levels of the system. Numerical results on typical GaAs/AlGaAs materials show that the decrease of the quantum dot radius blueshifts and amplifies the absorption coefficients as well as the refractive index changes, as expected. Additionally, an increase of the optical intensity and relaxation time considerably changes the absorption coefficients and the refractive index changes. - Highlights: Black-Right-Pointing-Pointer We consider a three-electron quantum dot in 2D in the presence of the Rashba spin-orbit interaction. Black-Right-Pointing-Pointer We present the exact wave functions and energy levels of the system. Black-Right-Pointing-Pointer We apply this model for GaAs/AlGaAs materials. Black-Right-Pointing-Pointer The detailed nonlinear optical properties have been investigated.
Energy Technology Data Exchange (ETDEWEB)
Reena Mary, A P; Anantharaman, M R [Department of Physics, Cochin University of Science and Technology, Cochin 682 022 (India); Suchand Sandeep, C S; Philip, Reji [Light and Matter Physics Group, Raman Research Institute, Sadashivanagar, Bangalore-560080 (India); Narayanan, T N; Moloney, Padraig; Ajayan, P M, E-mail: reji@rri.res.in, E-mail: mraiyer@yahoo.com [Department of Mechanical Engineering and Materials Science, Rice University, Houston, TX-77005 (United States)
2011-09-16
Oxide free stable metallic nanofluids have the potential for various applications such as in thermal management and inkjet printing apart from being a candidate system for fundamental studies. A stable suspension of nickel nanoparticles of {approx} 5 nm size has been realized by a modified two-step synthesis route. Structural characterization by x-ray diffraction and transmission electron microscopy shows that the nanoparticles are metallic and are phase pure. The nanoparticles exhibited superparamagnetic properties. The magneto-optical transmission properties of the nickel nanofluid (Ni-F) were investigated by linear optical dichroism measurements. The magnetic field dependent light transmission studies exhibited a polarization dependent optical absorption, known as optical dichroism, indicating that the nanoparticles suspended in the fluid are non-interacting and superparamagnetic in nature. The nonlinear optical limiting properties of Ni-F under high input optical fluence were then analyzed by an open aperture z-scan technique. The Ni-F exhibits a saturable absorption at moderate laser intensities while effective two-photon absorption is evident at higher intensities. The Ni-F appears to be a unique material for various optical devices such as field modulated gratings and optical switches which can be controlled by an external magnetic field.
Agrawal, Govind
2012-01-01
Since the 4e appeared, a fast evolution of the field has occurred. The 5e of this classic work provides an up-to-date account of the nonlinear phenomena occurring inside optical fibers, the basis of all our telecommunications infastructure as well as being used in the medical field. Reflecting the big developments in research, this new edition includes major new content: slow light effects, which offers a reduction in noise and power consumption and more ordered network traffic-stimulated Brillouin scattering; vectorial treatment of highly nonlinear fibers; and a brand new chapter o
Nonlinear mechanisms to Rogue events in the process of interaction between optical filaments
Kovachev, L M
2015-01-01
We investigate two types of nonlinear interaction between collinear femtosecond laser pulses with power slightly above the critical for self-focusing $P_{cr}$. In the first case we study energy exchange between filaments. The model describes this process through degenerate four-photon parametric mixing (FPPM) scheme and requests initial phase difference between the waves. When there are no initial phase difference between the pulses, the FPPM process does not work. In this case it is obtained the second type of interaction as merging between two, three or four filaments in a single filament with higher power. It is found that in the second case the interflow between the filaments has potential of interaction due to cross-phase modulation (CPM).
Electrifying photonic metamaterials for tunable nonlinear optics.
Kang, Lei; Cui, Yonghao; Lan, Shoufeng; Rodrigues, Sean P; Brongersma, Mark L; Cai, Wenshan
2014-08-11
Metamaterials have not only enabled unprecedented flexibility in producing unconventional optical properties that are not found in nature, they have also provided exciting potential to create customized nonlinear media with high-order properties correlated to linear behaviour. Two particularly compelling directions are active metamaterials, whose optical properties can be purposely tailored by external stimuli in a reversible manner, and nonlinear metamaterials, which enable intensity-dependent frequency conversion of light waves. Here, by exploring the interaction of these two directions, we leverage the electrical and optical functions simultaneously supported in nanostructured metals and demonstrate electrically controlled nonlinear optical processes from a metamaterial. Both second harmonic generation and optical rectification, enhanced by the resonance behaviour in the metamaterial absorber, are modulated externally with applied voltage signals. Our results reveal an opportunity to exploit optical metamaterials as self-contained, dynamic electro-optic systems with intrinsically embedded electrical functions and optical nonlinearities.
Essentials of nonlinear optics
Murti, Y V G S
2014-01-01
Current literature on Nonlinear Optics varies widely in terms of content, style, and coverage of specific topics, relative emphasis of areas and the depth of treatment. While most of these books are excellent resources for the researchers, there is a strong need for books appropriate for presenting the subject at the undergraduate or postgraduate levels in Universities. The need for such a book to serve as a textbook at the level of the bachelors and masters courses was felt by the authors while teaching courses on nonlinear optics to students of both science and engineering during the past two decades. This book has emerged from an attempt to address the requirement of presenting the subject at college level. A one-semester course covering the essentials can effectively be designed based on this.
Three-state interactions determine the second-order nonlinear optical response
Perez-Moreno, Javier
2016-01-01
Using the sum-rules, the sum-over-states expression for the diagonal term of first hyperpolarizability can be expressed as the sum of three-state interaction terms. We study the behavior of a generic three-state term to show that is possible to tune the contribution of resonant terms by tuning the spectrum of the molecule. When extrapolated to the off-resonance regime, the three-state interaction terms are shown to behave in a similar manner as the three-level model used to derive the fundamental limits. We finally show that most results derived using the three-level ansatz are general, and apply to molecules where more than three levels contribute to the second-order nonlinear response or/and far from optimization.
Remote Atmospheric Nonlinear Optical Magnetometry
2014-04-28
Boyd , Nonlinear Optics (Elsevier, Burlington, MA, 2008). [13] M. Scully and S. Zubairy, Quantum Optics (Cambridge U. Press, Cambridge, UK, 1997...Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6703--14-9548 Remote Atmospheric Nonlinear Optical Magnetometry PhilliP SPrangle...b. ABSTRACT c. THIS PAGE 18. NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Remote Atmospheric Nonlinear Optical Magnetometry Phillip Sprangle, Luke
Terahertz Nonlinear Optics in Semiconductors
DEFF Research Database (Denmark)
Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias C.
2013-01-01
We demonstrate the nonlinear optical effects – selfphase modulation and saturable absorption of a single-cycle THz pulse in a semiconductor. Resulting from THz-induced modulation of Drude plasma, these nonlinear optical effects, in particular, lead to self-shortening and nonlinear spectral...
Leslie, Thomas M.
1993-01-01
A focused approach to development and evaluation of organic polymer films for use in optoelectronics is presented. The issues and challenges that are addressed include: (1) material synthesis, purification, and the tailoring of the material properties; (2) deposition of uniform thin films by a variety of methods; (3) characterization of material physical properties (thermal, electrical, optical, and electro-optical); and (4) device fabrication and testing. Photonic materials, devices, and systems were identified as critical technology areas by the Department of Commerce and the Department of Defense. This approach offers strong integration of basic material issues through engineering applications by the development of materials that can be exploited as the active unit in a variety of polymeric thin film devices. Improved materials were developed with unprecedented purity and stability. The absorptive properties can be tailored and controlled to provide significant improvement in propagation losses and nonlinear performance. Furthermore, the materials were incorporated into polymers that are highly compatible with fabrication and patterning processes for integrated optical devices and circuits. By simultaneously addressing the issues of materials development and characterization, keeping device design and fabrication in mind, many obstacles were overcome for implementation of these polymeric materials and devices into systems. We intend to considerably improve the upper use temperature, poling stability, and compatibility with silicon based devices. The principal device application that was targeted is a linear electro-optic modulation etalon. Organic polymers need to be properly designed and coupled with existing integrated circuit technology to create new photonic devices for optical communication, image processing, other laser applications such as harmonic generation, and eventually optical computing. The progression from microscopic sample to a suitable film
Nonlinear Optical Terahertz Technology Project
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...
Focus issue introduction: nonlinear optics.
Boulanger, Benoît; Cundiff, Steven T; Gauthier, Daniel J; Karlsson, Magnus; Lu, Yan-Qing; Norwood, Robert A; Skryabin, Dmitry; Taira, Takunori
2011-11-07
It is now fifty years since the original observation of second harmonic generation ushered in the field of nonlinear optics, close on the heels of the invention of the laser. This feature issue celebrates this anniversary with papers that span the range from new nonlinear optical materials, through the increasingly novel methods that have been developed for phase matching, to emerging areas such as nonlinear metamaterials and plasmonic enhancement of optical properties. It is clear that the next fifty years of nonlinear optics will witness a proliferation of new applications with increasing technological impact.
Nonlinear optics with stationary pulses of light
Andre, A.; Bajcsy, M.; Zibrov, A. S.; Lukin, M. D.
2004-01-01
We show that the recently demonstrated technique for generating stationary pulses of light [Nature {\\bf 426}, 638 (2003)] can be extended to localize optical pulses in all three spatial dimensions in a resonant atomic medium. This method can be used to dramatically enhance the nonlinear interaction between weak optical pulses. In particular, we show that an efficient Kerr-like interaction between two pulses can be implemented as a sequence of several purely linear optical processes. The resul...
Quantum nonlinear optics without photons
Stassi, Roberto; Macrı, Vincenzo; Kockum, Anton Frisk; Di Stefano, Omar; Miranowicz, Adam; Savasta, Salvatore; Nori, Franco
2017-08-01
Spontaneous parametric down-conversion is a well-known process in quantum nonlinear optics in which a photon incident on a nonlinear crystal spontaneously splits into two photons. Here we propose an analogous physical process where one excited atom directly transfers its excitation to a pair of spatially separated atoms with probability approaching 1. The interaction is mediated by the exchange of virtual rather than real photons. This nonlinear atomic process is coherent and reversible, so the pair of excited atoms can transfer the excitation back to the first one: the atomic analog of sum-frequency generation of light. The parameters used to investigate this process correspond to experimentally demonstrated values in ultrastrong circuit quantum electrodynamics. This approach can be extended to realize other nonlinear interatomic processes, such as four-atom mixing, and is an attractive architecture for the realization of quantum devices on a chip. We show that four-qubit mixing can efficiently implement quantum repetition codes and, thus, can be used for error-correction codes.
Applications of nonlinear fiber optics
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
Focus issue introduction: nonlinear optics 2013.
Dadap, Jerry I; Karlsson, Magnus; Panoiu, Nicolae C
2013-12-16
Nonlinear Optics has continued to develop over the last few years at an extremely fast pace, with significant advances being reported in nonlinear optical metamaterials, optical signal processing, quantum optics, nonlinear optics at subwavelength scale, and biophotonics. These exciting new developments have generated significant potential for a broad spectrum of technological applications in which nonlinear-optical processes play a central role.
Nonlinear Optics: Principles and Applications
DEFF Research Database (Denmark)
Rottwitt, Karsten; Tidemand-Lichtenberg, Peter
As nonlinear optics further develops as a field of research in electromagnetic wave propagation, its state-of-the-art technologies will continue to strongly impact real-world applications in a variety of fields useful to the practicing scientist and engineer. From basic principles to examples...... of applications, Nonlinear Optics: Principles and Applications effectively bridges physics and mathematics with relevant applied material for real-world use. The book progresses naturally from fundamental aspects to illustrative examples, and presents a strong theoretical foundation that equips the reader...... and matter, this text focuses on the physical understanding of nonlinear optics, and explores optical material response functions in the time and frequency domain....
Field guide to nonlinear optics
Powers, Peter E
2013-01-01
Optomechanics is a field of mechanics that addresses the specific design challenges associated with optical systems. This [i]Field Guide [/i]describes how to mount optical components, as well as how to analyze a given design. It is intended for practicing optical and mechanical engineers whose work requires knowledge in both optics and mechanics. This Field Guide is designed for those looking for a condensed and concise source of key concepts, equations, and techniques for nonlinear optics. Topics covered include technologically important effects, recent developments in nonlinear optics
Interactive optomechanical coupling with nonlinear polaritonic systems
Bobrovska, N; Liew, T C H; Kyriienko, O
2016-01-01
We study a system of interacting matter quasiparticles strongly coupled to photons inside an optomechanical cavity. The resulting normal modes of the system are represented by hybrid polaritonic quasiparticles, which acquire effective nonlinearity. Its strength is influenced by the presence of the mechanical mode and depends on the resonance frequency of the cavity. This leads to an interactive type of optomechanical coupling, being distinct from the previously studied dispersive and dissipative couplings in optomechanical systems. The emergent interactive coupling is shown to generate effective optical nonlinearity terms of high order, being quartic in the polariton number. We consider particular systems of exciton-polaritons and dipolaritons, and show that the induced effective optical nonlinearity due to the interactive coupling can exceed in magnitude the strength of Kerr nonlinear terms, such as those arising from polariton-polariton interactions. As applications, we show that the higher order terms give...
Whittam, A J
2001-01-01
susceptibility from 26 pm/V (same film without octadecanoic acid) to 40 pm/V. This increase in the second-order susceptibility occurred even though the amount of NLO-active dye was effectively diluted by the addition of the inactive octadecanoic acid. The wavelength of the absorption maximum ranged from 346-440 nm and there was direct correlation between the susceptibilities and the transparency of the films at the harmonic wavelength. Hemicyanine dyes were synthesised, with the general formulae: - (a) C sub 1 sub 8 H sub 3 sub 7 -A sup + -[CH=CH-C sub 6 H sub 4] sub x -N(CH sub 3) sub 2 I (b) C sub 1 sub 8 H sub 3 sub 7 -A sup + -[CH=CH] sub y -C sub 6 H sub 4 -N(CH sub 3) sub 2 I where A sup + is a pyridinium or isoquinolinium acceptor, and x = 1 or 2, and y = 1 or 2. The optically nonlinear dyes were investigated via the Langmuir-Blodgett (LB) technique. The dyes all produced isotherm data, with molecular areas of 22-60 A sup 2 per molecule, which are consistent with the cross-sectional areas of the chromo...
Completely integrable models of nonlinear optics
Indian Academy of Sciences (India)
Andrey I Maimistov
2001-11-01
The models of the nonlinear optics in which solitons appeared are considered. These models are of paramount importance in studies of nonlinear wave phenomena. The classical examples of phenomena of this kind are the self-focusing, self-induced transparency and parametric interaction of three waves. At present there are a number of theories based on completely integrable systems of equations, which are, both, generations of the original known models and new ones. The modiﬁed Korteweg-de Vries equation, the nonlinear Schrödinger equation, the derivative nonlinear Schrödinger equation, Sine–Gordon equation, the reduced Maxwell–Bloch equation, Hirota equation, the principal chiral ﬁeld equations, and the equations of massive Thirring model are some soliton equations, which are usually to be found in nonlinear optics theory.
Nonlinear optics: the next decade.
Kivshar, Yuri S
2008-12-22
This paper concludes the Focus Serial assembled of invited papers in key areas of nonlinear optics (Editors: J.M. Dudley and R.W. Boyd), and it discusses new directions for future research in this field.
Oscillating solitons in nonlinear optics
Indian Academy of Sciences (India)
Lin Xiao-Gang; Liu Wen-Jun; Lei Ming
2016-03-01
Oscillating solitons are obtained in nonlinear optics. Analytical study of the variable coefficient nonlinear Schrödinger equation, which is used to describe the soliton propagation in those systems, is carried out using the Hirota’s bilinear method. The bilinear forms and analytic soliton solutions are derived, and the relevant properties and features of oscillating solitons are illustrated. Oscillating solitons are controlled by the reciprocal of the group velocity and Kerr nonlinearity. Results of this paper will be valuable to the study of dispersion-managed optical communication system and mode-locked fibre lasers.
Nonlinear optics and organic materials
Energy Technology Data Exchange (ETDEWEB)
Shen, Y.R.
1994-07-01
We shall consider an interesting topic relating nonlinear optics and organic materials: how nonlinear optics can be used to study organic materials. One of the main differences between linear and nonlinear responses of a medium to incoming radiation is in their symmetries. It leads to the possibility that some properties of the medium could be more sensitively probed by nonlinear, rather than linear, optical means, or vise versa. A well-known example is that some vibrational modes of a medium could be Raman-active but infrared-inactive, and would be more readily observed by Raman scattering, which is a two-photon transition process. In this paper, we shall discuss, with the help of three examples, how we can use second harmonic generation (SHG) and sum frequency generation (SFG) to obtain unique information about a material. We shall focus on thin films, surfaces, and interfaces.
Enhanced optical nonlinearities in air-cladding silicon pedestal waveguides
Zhang, Yaojing; Yao, Yifei; Tsang, Hon Ki
2016-01-01
The third-order optical nonlinearity in optical waveguides has found applications in optical switching, optical wavelength conversion, optical frequency comb generation, and ultrafast optical signal processing. The development of an integrated waveguide platform with a high nonlinearity is therefore important for nonlinear integrated photonics. Here, we report the observation of an enhancement in the nonlinearity of an air-cladding silicon pedestal waveguide. We observe enhanced nonlinear spectral broadening compared to a conventional silicon-on-insulator waveguide. At the center wavelength of 1555 nm, the nonlinear-index coefficient of air-cladding silicon pedestal waveguide is measured to be about 5% larger than that of a conventional silicon-on-insulator waveguide. We observe enhanced spectral broadening from self-phase modulation of an optical pulse in the pedestal waveguide. The interaction of light with the confined acoustic phonons in the pedestal structure gives rise to a larger nonlinear-index coeffi...
Yashkir, O. V.; Yashkir, Yu N.
1987-11-01
An investigation is made of nonlinear optical interaction of light propagating in a planar waveguide with surface polaritons. Reduced wave equations for the amplitudes of the waveguide modes and surface polaritons are used to study the characteristics of generation of surface polaritons of difference frequency, parametric frequency up-conversion of the polaritons, and stimulated Raman scattering by the polaritons. An analysis is made of the characteristic properties of the investigated nonlinear optical processes.
Nonlinear Optics and Turbulence
1992-10-01
currently at Queen Mary College, London Patrick Dunne, (Ph.D., 1987, M.I.T., Hydrodynamic Stability, Nonlinear Waves), 1987-1988. Alecsander Dyachenko...U I I I U I I 3 9 3 V. BIOGRAPHIES A. FACULTY BRUCE BAYLY, 31, Ph.D. 1986, Princeton University. Postdoctoral visiting member 1986-88 at Courant...Caputo, A. C. Newell, and M. Shelley , "Nonlinear Wave Propagation Through a Random Medium and Soliton Tunneling", Integrable Systems and
Directory of Open Access Journals (Sweden)
N. A. Veretenov
2014-09-01
and their correlation with boundaries of bistability regions has been carried out. Obtained results give the possibility to determine more rigorously the parameters region, where nonlinear effects can be observed. They can be used for development of optical logic devices and, in particular, molecular memory circuits.
New nonlinear optical materials based on ferrofluids
Energy Technology Data Exchange (ETDEWEB)
Huang, J P [Department of Physics, Fudan University, Shanghai 200433 (China); Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz (Germany); Institute of Theoretical Physics, Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Yu, K W [Department of Physics, Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Institute of Theoretical Physics, Chinese University of Hong Kong, Shatin, NT, Hong Kong (China)
2006-01-01
We exploit theoretically a new class of magneto-controlled nonlinear optical material based on ferrofluids in which ferromagnetic nanoparticles are coated with a nonmagnetic metallic nonlinear shell. Such an optical material can have anisotropic nonlinear optical properties and a giant enhancement of nonlinearity, as well as an attractive figure of merit.
Terahertz semiconductor nonlinear optics
DEFF Research Database (Denmark)
Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias
2013-01-01
nonlinearity in doped semiconductors originates from the near-instantaneous heating of free electrons in the ponderomotive potential created by electric field of the THz pulse, leading to ultrafast increase of electron effective mass by intervalley scattering. Modification of effective mass in turn leads...
Nonlinear Light-Matter Interactions in Metamaterials
O'Brien, Kevin Patrick
Metamaterials possess extraordinary linear optical properties never observed in natural materials such as a negative refractive index, enabling exciting applications such as super resolution imaging and cloaking. In this thesis, we explore the equally extraordinary nonlinear properties of metamaterials. Nonlinear optics, the study of light-matter interactions where the optical fields are strong enough to change material properties, has fundamental importance to physics, chemistry, and material science as a non-destructive probe of material properties and has important technological applications such as entangled photon generation and frequency conversion. Due to their ability to manipulate both linear and nonlinear light matter interactions through sub-wavelength structuring, metamaterials are a promising direction for both fundamental and applied nonlinear optics research. We perform the first experiments on nonlinear propagation in bulk zero and negative index optical metamaterials and demonstrate that a zero index material can phase match four wave mixing processes in ways not possible in finite index materials. In addition, we demonstrate the ability of nonlinear scattering theory to describe the geometry dependence of second and third harmonic generation in plasmonic nanostructures. As an application of nonlinear metamaterials, we propose a phase matching technique called "resonant phase matching" to increase the gain and bandwidth of Josephson junction traveling wave parametric amplifiers. With collaborators, we demonstrate a best in class amplifier for superconducting qubit readout--over 20 dB gain with near quantum limited noise performance with a bandwidth and dynamic range an order of magnitude larger than alternative devices. In conclusion, we have demonstrated several ways in which nonlinear metamaterials surpass their natural counterparts. We look forward to the future of the field where nonlinear and quantum metamaterials will enable further new
Resource Letter NO-1: Nonlinear Optics
Garmire, Elsa
2011-03-01
This Resource Letter provides a guide to the literature on nonlinear optics. Books, journals, and websites are introduced that cover the general subject. Journal articles and websites are cited covering the following topics: second-order nonlinearities in transparent media including second-harmonic generation and optical parametric oscillation, third-order and higher nonlinearities, nonlinear refractive index, absorptive nonlinearities such as saturable absorption and multiphoton absorption, and scattering nonlinearities such as stimulated Raman scattering and stimulated Brillouin scattering. Steady-state and transient phenomena, fiber optics, solitons, nonlinear wave mixing, optical phase conjugation, nonlinear spectroscopy, and multiphoton microscopy are all outlined.
Nonlinear Optics of Hexaphenyl Nanofibers
DEFF Research Database (Denmark)
Balzer, Frank; Al-Shamery, Katharina; Neuendorf, Rolf
2003-01-01
measurements reveal that the nonlinear optical transition dipole moment is oriented with an angle of 75° with respect to the needles long axes. The absolute value of the macroscopic second-order susceptibility, averaged over a size distribution of p-6P nanoaggregates, is estimated to be of the order of 6...
Rotational Doppler effect in nonlinear optics
Li, Guixin; Zentgraf, Thomas; Zhang, Shuang
2016-08-01
The translational Doppler effect of electromagnetic and sound waves has been successfully applied in measurements of the speed and direction of vehicles, astronomical objects and blood flow in human bodies, and for the Global Positioning System. The Doppler effect plays a key role for some important quantum phenomena such as the broadened emission spectra of atoms and has benefited cooling and trapping of atoms with laser light. Despite numerous successful applications of the translational Doppler effect, it fails to measure the rotation frequency of a spinning object when the probing wave propagates along its rotation axis. This constraint was circumvented by deploying the angular momentum of electromagnetic waves--the so-called rotational Doppler effect. Here, we report on the demonstration of rotational Doppler shift in nonlinear optics. The Doppler frequency shift is determined for the second harmonic generation of a circularly polarized beam passing through a spinning nonlinear optical crystal with three-fold rotational symmetry. We find that the second harmonic generation signal with circular polarization opposite to that of the fundamental beam experiences a Doppler shift of three times the rotation frequency of the optical crystal. This demonstration is of fundamental significance in nonlinear optics, as it provides us with insight into the interaction of light with moving media in the nonlinear optical regime.
Energy Technology Data Exchange (ETDEWEB)
Sentman, L.H.; Nayfeh, M.H.
1983-12-01
This research is an integrated theoretical and experimental investigation of the nonlinear interactions which may occur between the chemical kinetics, the fluid dynamics and the unstable resonator of a continuous wave fluid flow laser. The objectives of this grant were to measure the frequency and amplitude of the time dependent pulsations in the power spectral output which have been predicted to occur in cw chemical lasers employing unstable resonators to extract power.
Nonlinear fiber optics formerly quantum electronics
Agrawal, Govind
1995-01-01
The field of nonlinear fiber optics has grown substantially since the First Edition of Nonlinear Fiber Optics, published in 1989. Like the First Edition, this Second Edition is a comprehensive, tutorial, and up-to-date account of nonlinear optical phenomena in fiber optics. It synthesizes widely scattered research material and presents it in an accessible manner for students and researchers already engaged in or wishing to enter the field of nonlinear fiber optics. Particular attention is paid to the importance of nonlinear effects in the design of optical fiber communication systems. This is
Bidirectional all-optical switches based on highly nonlinear optical fibers
Liu, Wenjun; Yang, Chunyu; Liu, Mengli; Yu, Weitian; Zhang, Yujia; Lei, Ming; Wei, Zhiyi
2017-05-01
All-optical switches have become one of the research focuses of nonlinear optics due to their fast switching speed. They have been applied in such fields as ultrafast optics, all-optical communication and all-optical networks. In this paper, based on symbolic computation, bidirectional all-optical switches are presented using analytic two-soliton solutions. Various types of soliton interactions are analyzed through choosing the different parameters of high-order dispersion and nonlinearity. Results indicate that bidirectional all-optical switches can be effectively achieved using highly nonlinear optical fibers.
Unsymmetrical squaraines for nonlinear optical materials
Marder, Seth R. (Inventor); Chen, Chin-Ti (Inventor); Cheng, Lap-Tak (Inventor)
1996-01-01
Compositions for use in non-linear optical devices. The compositions have first molecular electronic hyperpolarizability (.beta.) either positive or negative in sign and therefore display second order non-linear optical properties when incorporated into non-linear optical devices.
Liquid-state acoustically-nonlinear nanoplasmonic source of optical frequency combs
Maksymov, Ivan S
2016-01-01
Nonlinear acoustic interactions in liquids are effectively stronger than nonlinear optical interactions in solids. Thus, harnessing these interactions will offer new possibilities in the design of ultra-compact nonlinear photonic devices. We theoretically demonstrate a hybrid, liquid-state and nanoplasmonic, source of optical frequency combs compatible with fibre-optic technology. This source relies on a nanoantenna to harness the strength of nonlinear acoustic effects and synthesise optical spectra from ultrasound.
Quantum Computation with Nonlinear Optics
Liu, Yang; Zhang, Wen-Hong; Zhang, Cun-Lin; Long, Gui-Lu
2008-01-01
We propose a scheme of quantum computation with nonlinear quantum optics. Polarization states of photons are used for qubits. Photons with different frequencies represent different qubits. Single qubit rotation operation is implemented through optical elements like the Faraday polarization rotator. Photons are separated into different optical paths, or merged into a single optical path using dichromatic mirrors. The controlled-NOT gate between two qubits is implemented by the proper combination of parametric up and down conversions. This scheme has the following features: (1) No auxiliary qubits are required in the controlled-NOT gate operation; (2) No measurement is required in the course of the computation; (3) It is resource efficient and conceptually simple.
Quantum Computation with Nonlinear Optics
Institute of Scientific and Technical Information of China (English)
LU Ke; LIU Yang; LIN Zhen-Quan; ZHANG Wen-Hong; SUN Yun-Fei; ZHANG Cun-Lin; LONG Gui-Lu
2008-01-01
We propose a scheme of quantum computation with nonlinear quantum optics. Polarization states of photons are used for qubits. Photons with different frequencies represent different qubits. Single qubit rotation operation is implemented through optical elements like the Faraday polarization rotator. Photons are separated into different optical paths, or merged into a single optical path using dichromatic mirrors. The controlled-NOT gate between two qubits is implemented by the proper combination of parametric up and down conversions. This scheme has the following features: (1) No auxiliary qubits are required in the controlled-NOT gate operation; (2) No measurement is required in the courseof the computation; (3) It is resource efficient and conceptually simple.
Organosilicon Polymeric Nonlinear Optical Materials for Optical Switching and Modulation
1994-02-28
Organosilicon Polymeric Nonlinear Optical Materials for Optical C: F49620-93-C-0039 Switching and Modulation 6. AUTHOR(S) Mr. Sandip K. Sengupta, Dr...D FINAL REPORT for Organosilicon Polymeric Nonlinear Optical Materials for Optical Switching and Modulation Prepared for: USAF, AFMC (AFOSR) Air Force...34Organosilicon Polymeric Nonlinear Optical Materials for Optical Switching and Modulation," contract number F49620-93-C-0039. The work has been performed by Dr
Mukamel, Shaul
2016-07-01
Nonlinear spectroscopy signals detected by fluorescence from dilute samples of N non-interacting molecules are usually adequately described by simply multiplying the single molecule response by N. We show that signals that scale with higher powers of N are generated by the joint detection of several particles. This can be accomplished by phase sensitive detection such as phase cycling, photo-acoustic modulation, or by Hanbury-Brown Twiss photon coincidence. Such measurements can dissect the ensemble according to the number of excited particles.
Extremely nonlocal optical nonlinearities in atoms trapped near a waveguide
Shahmoon, Ephraim; Stimming, Hans Peter; Mazets, Igor; Kurizki, Gershon
2014-01-01
Nonlinear optical phenomena are typically local. Here we predict the possibility of highly nonlocal optical nonlinearities for light propagating in atomic media trapped near a nano-waveguide, where long-range interactions between the atoms can be tailored. When the atoms are in an electromagnetically-induced transparency configuration, the atomic interactions are translated to long-range interactions between photons and thus to highly nonlocal optical nonlinearities. We derive and analyze the governing nonlinear propagation equation, finding a roton-like excitation spectrum for light and the emergence of long-range order in its output intensity. These predictions open the door to studies of unexplored wave dynamics and many-body physics with highly-nonlocal interactions of optical fields in one dimension.
Extreme nonlinear optics and laser damage
Maldutis, Evaldas
2010-11-01
The study of laser induced damage threshold caused by series of identical laser pulses (LID-T-N) on gamma radiation resistant glasses and their analogs is performed applying know-how ultra stable laser radiation. The presented results and analysis of earlier received results show that nonlinear optical phenomena in extreme conditions of interaction are different from the traditional nonlinear optical processes, because they depend not only on intensity of electromagnetic field of laser radiation, but also on the pulse number in series of identical laser pulses. This range of laser intensities is not wide; it is different for each material and determines the range of Extreme Nonlinear Optics. The dependence of LID-T-N on pulse number N for different kinds of high quality transparent glasses was observed. The study of dynamics of these processes (i.e. the study of dependence on N) at different intensities in series of incident laser pulses provides new information about properties of the materials useful for studying laser damage fundamentals and their application. The expectation that gamma radiation resistant glasses could give useful information for technology of resistant optics for high power lasers has not proved. The received results well correspond with the earlier proposed model of laser damage.
Rigorous theory of molecular orientational nonlinear optics
Directory of Open Access Journals (Sweden)
Chong Hoon Kwak
2015-01-01
Full Text Available Classical statistical mechanics of the molecular optics theory proposed by Buckingham [A. D. Buckingham and J. A. Pople, Proc. Phys. Soc. A 68, 905 (1955] has been extended to describe the field induced molecular orientational polarization effects on nonlinear optics. In this paper, we present the generalized molecular orientational nonlinear optical processes (MONLO through the calculation of the classical orientational averaging using the Boltzmann type time-averaged orientational interaction energy in the randomly oriented molecular system under the influence of applied electric fields. The focal points of the calculation are (1 the derivation of rigorous tensorial components of the effective molecular hyperpolarizabilities, (2 the molecular orientational polarizations and the electronic polarizations including the well-known third-order dc polarization, dc electric field induced Kerr effect (dc Kerr effect, optical Kerr effect (OKE, dc electric field induced second harmonic generation (EFISH, degenerate four wave mixing (DFWM and third harmonic generation (THG. We also present some of the new predictive MONLO processes. For second-order MONLO, second-order optical rectification (SOR, Pockels effect and difference frequency generation (DFG are described in terms of the anisotropic coefficients of first hyperpolarizability. And, for third-order MONLO, third-order optical rectification (TOR, dc electric field induced difference frequency generation (EFIDFG and pump-probe transmission are presented.
Graphene - a rather ordinary nonlinear optical material
khurgin, Jacob B
2014-01-01
An analytical expression for the nonlinear refractive index of graphene has been derived and used to obtain the performance metrics of third order nonlinear devices using graphene as a nonlinear medium. None of the metrics is found to be superior to the existing nonlinear optical materials.
Nonlinear optical crystals a complete survey
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...
The quantum theory of nonlinear optics
Drummond, Peter D
2014-01-01
Playing a prominent role in communications, quantum science and laser physics, quantum nonlinear optics is an increasingly important field. This book presents a self-contained treatment of field quantization and covers topics such as the canonical formalism for fields, phase-space representations and the encompassing problem of quantization of electrodynamics in linear and nonlinear media. Starting with a summary of classical nonlinear optics, it then explains in detail the calculation techniques for quantum nonlinear optical systems and their applications, quantum and classical noise sources in optical fibers and applications of nonlinear optics to quantum information science. Supplemented by end-of-chapter exercises and detailed examples of calculation techniques in different systems, this book is a valuable resource for graduate students and researchers in nonlinear optics, condensed matter physics, quantum information and atomic physics. A solid foundation in quantum mechanics and classical electrodynamic...
Nonlinear Photonics and Novel Optical Phenomena
Morandotti, Roberto
2012-01-01
Nonlinear Photonics and Novel Optical Phenomena contains contributed chapters from leading experts in nonlinear optics and photonics, and provides a comprehensive survey of fundamental concepts as well as hot topics in current research on nonlinear optical waves and related novel phenomena. The book covers self-accelerating airy beams, integrated photonics based on high index doped-silica glass, linear and nonlinear spatial beam dynamics in photonic lattices and waveguide arrays, polariton solitons and localized structures in semiconductor microcavities, terahertz waves, and other novel phenomena in different nanophotonic and optical systems.
Fibre-optic nonlinear optical microscopy and endoscopy.
Fu, L; Gu, M
2007-06-01
Nonlinear optical microscopy has been an indispensable laboratory tool of high-resolution imaging in thick tissue and live animals. Rapid developments of fibre-optic components in terms of growing functionality and decreasing size provide enormous opportunities for innovations in nonlinear optical microscopy. Fibre-based nonlinear optical endoscopy is the sole instrumentation to permit the cellular imaging within hollow tissue tracts or solid organs that are inaccessible to a conventional optical microscope. This article reviews the current development of fibre-optic nonlinear optical microscopy and endoscopy, which includes crucial technologies for miniaturized nonlinear optical microscopy and their embodiments of endoscopic systems. A particular attention is given to several classes of photonic crystal fibres that have been applied to nonlinear optical microscopy due to their unique properties for ultrashort pulse delivery and signal collection. Furthermore, fibre-optic nonlinear optical imaging systems can be classified into portable microscopes suitable for imaging behaving animals, rigid endoscopes that allow for deep tissue imaging with minimally invasive manners, and flexible endoscopes enabling imaging of internal organs. Fibre-optic nonlinear optical endoscopy is coming of age and a paradigm shift leading to optical microscope tools for early cancer detection and minimally invasive surgery.
Progress in nonlinear nano-optics
Lienau, Christoph; Grunwald, Rüdiger
2015-01-01
This book presents the state of the art in nonlinear nanostructures for ultrafast laser applications. Most recent results in two emerging fields are presented: (i) generation of laser-induced nanostructures in materials like metals, metal oxides and semiconductors, and (ii) ultrafast excitation and energy transfer in nanoscale physical, chemical and hybrid systems. Particular emphasis is laid on the up-to-date controversially discussed mechanisms of sub-wavelength ripple formation including models of self-organized material transport and multiphoton excitation channels, nonlinear optics of plasmonic structures (nanotips, nanowires, 3D-metamaterials), and energy localization and transport on ultrafast time scale and spatial nanoscale. High-resolution spectroscopy, simulation and characterization techniques are reported. New applications of ultrashort-pulsed lasers for materials processing and the use of nanostructured materials for characterizing laser fields and laser-matter-interactions are discussed.
Photon interaction study of organic nonlinear optical materials in the energy range 122-1330 keV
Awasarmol, Vishal V.; Gaikwad, Dhammajyot K.; Raut, Siddheshwar D.; Pawar, Pravina P.
2017-01-01
In the present study, the mass attenuation coefficient (μm) of six organic nonlinear optical materials has been calculated in the energy range 122-1330 keV and compared with the obtained values from the WinXCOM program. It is found that there is a good agreement between theoretical and experimental values (<3%). The linear attenuation coefficients (μ) total atomic cross section (σt, a), and total electronic cross section (σt, el) have also been calculated from the obtained μm values and their variations with photon energy have been plotted. From the present work, it is observed that the variation of obtained values of μm, μ, σt, a, and σt, el strongly depends on the photon energy and decreases or increases due to chemical composition and density of the sample. All the samples have been studied extensively using transmission method with a view to utilize the material for radiation dosimetry. Investigated samples are good material for radiation dosimetry due their low effective atomic number. The mass attenuation coefficient (μm), linear attenuation coefficients (μ), total atomic cross section (σt, a), total electronic cross section (σt, el), effective atomic numbers (Zeff), molar extinction coefficient (ε), mass energy absorption coefficient (μen/ρ) and effective atomic energy absorption cross section (σa, en) of all sample materials have been carried out and transmission curves have been plotted. The transmission curve shows that the variation of all sample materials decreases with increasing photon energy.
Nonlinear optics quantum computing with circuit QED.
Adhikari, Prabin; Hafezi, Mohammad; Taylor, J M
2013-02-08
One approach to quantum information processing is to use photons as quantum bits and rely on linear optical elements for most operations. However, some optical nonlinearity is necessary to enable universal quantum computing. Here, we suggest a circuit-QED approach to nonlinear optics quantum computing in the microwave regime, including a deterministic two-photon phase gate. Our specific example uses a hybrid quantum system comprising a LC resonator coupled to a superconducting flux qubit to implement a nonlinear coupling. Compared to the self-Kerr nonlinearity, we find that our approach has improved tolerance to noise in the qubit while maintaining fast operation.
Design of Organic Nonlinear Optical Materials
1990-06-01
This project deals with a new approach to designing organic nonlinear optical materials for second harmonic generation based on the use of hydrogen...patterns for even simple organic molecules. For organic nonlinear optical materials this dilemma means that even the most promising organic molecule may
Nonlinear and quantum optics with whispering gallery resonators
Strekalov, Dmitry V.; Marquardt, Christoph; Matsko, Andrey B.; Schwefel, Harald G. L.; Leuchs, Gerd
2016-12-01
Optical whispering gallery modes (WGMs) derive their name from a famous acoustic phenomenon of guiding a wave by a curved boundary observed nearly a century ago. This phenomenon has a rather general nature, equally applicable to sound and all other waves. It enables resonators of unique properties attractive both in science and engineering. Very high quality factors of optical WGM resonators persisting in a wide wavelength range spanning from radio frequencies to ultraviolet light, their small mode volume, and tunable in- and out- coupling make them exceptionally efficient for nonlinear optical applications. Nonlinear optics facilitates interaction of photons with each other and with other physical systems, and is of prime importance in quantum optics. In this paper we review numerous applications of WGM resonators in nonlinear and quantum optics. We outline the current areas of interest, summarize progress, highlight difficulties, and discuss possible future development trends in these areas.
Nonlinear and Quantum Optics with Whispering Gallery Resonators
Strekalov, Dmitry V; Matsko, Andrey B; Schwefel, Harald G L; Leuchs, Gerd
2016-01-01
Optical Whispering Gallery Modes (WGMs) derive their name from a famous acoustic phenomenon of guiding a wave by a curved boundary observed nearly a century ago. This phenomenon was later realized to have a rather general nature, equally applicable to sound and all other waves, but in particular also to electromagnetic waves ranging from radio frequencies to ultraviolet light. Very high quality factors of optical WGM resonators persisting in a wide wavelength range, their small mode volume, and tunable in- and out- coupling make them exceptionally efficient for nonlinear optical applications. Nonlinear optics facilitates interaction of photons with each other and with other physical systems, and is of prime importance in quantum optics. In this paper we review numerous applications of WGM resonators in nonlinear and quantum optics. We outline the current areas of interest, summarize progress, highlight difficulties, and discuss possible future development trends in these areas.
A Web Tool for Research in Nonlinear Optics
Prikhod'ko, Nikolay V.; Abramovsky, Viktor A.; Abramovskaya, Natalia V.; Demichev, Andrey P.; Kryukov, Alexandr P.; Polyakov, Stanislav P.
2016-02-01
This paper presents a project of developing the web platform called WebNLO for computer modeling of nonlinear optics phenomena. We discuss a general scheme of the platform and a model for interaction between the platform modules. The platform is built as a set of interacting RESTful web services (SaaS approach). Users can interact with the platform through a web browser or command line interface. Such a resource has no analogues in the field of nonlinear optics and will be created for the first time therefore allowing researchers to access high-performance computing resources that will significantly reduce the cost of the research and development process.
Interaction nonlinearity in asphalt binders
Motamed, Arash; Bhasin, Amit; Liechti, Kenneth M.
2012-05-01
Asphalt mixtures are complex composites that comprise aggregate, asphalt binder, and air. Several research studies have shown that the mechanical behavior of the asphalt mixture is strongly influenced by the matrix, i.e. the asphalt binder. Characterization and a thorough understanding of the binder behavior is the first and crucial step towards developing an accurate constitutive model for the composite. Accurate constitutive models for the constituent materials are critical to ensure accurate performance predictions at a material and structural level using micromechanics. This paper presents the findings from a systematic investigation into the nature of the linear and nonlinear response of asphalt binders subjected to different types of loading using the Dynamic Shear Rheometer (DSR). Laboratory test data show that a compressive normal force is generated in an axially constrained specimen subjected to torsional shear. This paper investigates the source of this normal force and demonstrates that the asphalt binder can dilate when subjected to shear loads. This paper also presents the findings from a study conducted to investigate the source of the nonlinearity in the asphalt binder. Test results demonstrate that the application of cyclic shear loads results in the development of a normal force and a concomitant reduction in the dynamic shear modulus. This form of nonlinear response is referred to as an "interaction nonlinearity". A combination of experimental and analytical tools is used to demonstrate and verify the presence of this interaction nonlinearity in asphalt binders. The findings from this study highlight the importance of modeling the mechanical behavior of asphalt binders based on the overall stress state of the material.
Optical Nonlinearities in Chalcogenide Glasses and their Applications
Zakery, A
2007-01-01
Photonics, which uses photons for information and image processing, has been labeled the technology of the 21st century, for which non-linear optical processes provide the key functions of frequency conversion and optical switching. Chalcogenide glass fiber is one of the most promising candidates for use as a non-linear optical medium because of its high optical nonlinearity and long interaction length. Since the chalcogenide glass fibers transmit into the IR, there are numerous potential applications in the civil, medical and military areas. One of the most exciting developments in the future is going to be in the area of rare-earth ion doping of chalcogenide fibers for IR fluorescence emission. The IR light sources, lasers and amplifiers developed using this phenomena will be very useful in civil, medical and military applications. Remote IR spectroscopy and imaging using flexible fibers will be realized for applications. Other future research areas which will inevitably be explored includes non-linear opti...
Nonlinear optical properties of ultrathin metal layers
DEFF Research Database (Denmark)
Lysenko, Oleg
2016-01-01
. The optical characterization of the plasmonic waveguides is performed using femtosecond and picosecond optical pulses. Two nonlinear optical effects in the strip plasmonic waveguides are experimentally observed and reported. The first effect is the nonlinear power transmission of the plasmonic mode......-order nonlinear susceptibility of the plasmonic mode in the gold strip waveguides significantly depends on the metal layer thickness and laser pulse duration. This dependence is explained in detail in terms of the free-electron temporal dynamics in gold. The third-order nonlinear susceptibility of the gold layer...... duration dependence of the third-order nonlinear susceptibility of gold is calculated in the broad range from tens of femtoseconds to tens of picoseconds using the two-temperature model of the free-electron temporal dynamics of gold, and shows the saturation of the thirdorder nonlinear susceptibility...
1992-02-13
niobate and absolute measurements of nonlinear optical coefficients of six different commonly used nonlinear optical materials. The refractometry data for...applied radiation and is now an established technology for Nd:YAG lasers. Optical parametric oscillation and amplification provide a method of generating...continuously tunable output -3- The relative advantages of nonlinear optical frequency conversion compared to other methods for the generation of near
Nonlinear optics at low powers: Alternative mechanism of on-chip optical frequency comb generation
Rogov, Andrei S.; Narimanov, Evgenii E.
2016-12-01
Nonlinear optical effects provide a natural way of light manipulation and interaction and form the foundation of applied photonics, from high-speed signal processing and telecommunication to ultrahigh-bandwidth interconnects and information processing. However, relatively weak nonlinear response at optical frequencies calls for operation at high optical powers or boosting efficiency of nonlinear parametric processes by enhancing local-field intensity with high-quality-factor resonators near cavity resonance, resulting in reduced operational bandwidth and increased loss due to multiphoton absorption. We present an alternative to this conventional approach, with strong nonlinear optical effects at low local intensities, based on period-doubling bifurcations near nonlinear cavity antiresonance and apply it to low-power optical frequency comb generation in a silicon chip.
Nonlinear optics at low powers: new mechanism of on-chip optical frequency comb generation
Rogov, Andrei
2016-01-01
Nonlinear optical effects provide a natural way of light manipulation and interaction, and form the foundation of applied photonics -- from high-speed signal processing and telecommunication, to ultra-high bandwidth interconnects and information processing. However, relatively weak nonlinear response at optical frequencies calls for operation at high optical powers, or boosting efficiency of nonlinear parametric processes by enhancing local field intensity with high quality-factor resonators near cavity resonance, resulting in reduced operational bandwidth and increased loss due to multi-photon absorption. Here, we present an alternative to this conventional approach, with strong nonlinear optical effects at substantially lower local intensities, based on period-doubling bifurcations near nonlinear cavity anti-resonance, and apply it to low-power optical comb generation in a silicon chip.
Metamaterials with tailored nonlinear optical response.
Husu, Hannu; Siikanen, Roope; Mäkitalo, Jouni; Lehtolahti, Joonas; Laukkanen, Janne; Kuittinen, Markku; Kauranen, Martti
2012-02-08
We demonstrate that the second-order nonlinear optical response of noncentrosymmetric metal nanoparticles (metamolecules) can be efficiently controlled by their mutual ordering in an array. Two samples with minor change in ordering have nonlinear responses differing by a factor of up to 50. The results arise from polarization-dependent plasmonic resonances modified by long-range coupling associated with metamolecular ordering. The approach opens new ways for tailoring the nonlinear responses of metamaterials and their tensorial properties.
Nonlinear soliton matching between optical fibers
DEFF Research Database (Denmark)
Agger, Christian; Sørensen, Simon Toft; Thomsen, Carsten L.
2011-01-01
In this Letter, we propose a generic nonlinear coupling coefficient, η2 NL ¼ ηjγ=β2jfiber2=jγ=β2jfiber1, which gives a quantitative measure for the efficiency of nonlinear matching of optical fibers by describing how a fundamental soliton couples from one fiber into another. Specifically, we use η...
All-optical switching in optically induced nonlinear waveguide couplers
Energy Technology Data Exchange (ETDEWEB)
Diebel, Falko, E-mail: falko.diebel@uni-muenster.de; Boguslawski, Martin; Rose, Patrick; Denz, Cornelia [Institut für Angewandte Physik and Center for Nonlinear Science (CeNoS), Westfälische Wilhelms-Universität Münster, 48149 Münster (Germany); Leykam, Daniel; Desyatnikov, Anton S. [Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)
2014-06-30
We experimentally demonstrate all-optical vortex switching in nonlinear coupled waveguide arrays optically induced in photorefractive media. Our technique is based on multiplexing of nondiffracting Bessel beams to induce various types of waveguide configurations. Using double- and quadruple-well potentials, we demonstrate precise control over the coupling strength between waveguides, the linear and nonlinear dynamics and symmetry-breaking bifurcations of guided light, and a power-controlled optical vortex switch.
Development of Organic Nonlinear Optical Materials
1992-10-22
10 SOVRCE Of FUNO#NG NUM#E*S DM J .j PROGRAM PR0jECT TA5. ~ *0. I1I TITLE &Vila* So.Ivety ClaUMC400NJ Development of Organic NonLinear Optical Materials (U...0102-LF-014-6603 UNCLASSIFIED (U) AFOSR Contract: F4962040-C 0097 FINAL REPORT Development of Organic Nonlinear Optical Materials by J. Sounnk IL
DEFF Research Database (Denmark)
Bache, Morten; Bang, Ole; Zhou, Binbin;
2011-01-01
When ultrafast noncritical cascaded second-harmonic generation of energetic femtosecond pulses occur in a bulk lithium niobate crystal optical Cherenkov waves are formed in the near- to mid-IR. Numerical simulations show that the few-cycle solitons radiate Cherenkov (dispersive) waves in the λ = 2...... efficiency is up to 25%. Thus, optical Cherenkov waves formed with cascaded nonlinearities could become an efficient source of energetic near- to mid-IR few-cycle pulses....
DEFF Research Database (Denmark)
Bache, Morten; Bang, Ole; Zhou, Binbin
2011-01-01
Through cascaded second-harmonic generation, few-cycle solitons can form that resonantly emit strongly red-shifted optical Cherenkov radiation. Numerical simulations show that such dispersive waves can be an efficient source of near- to mid-IR few-cycle broadband pulses....
Advances in nonlinear optical materials and devices
Byer, Robert L.
1991-01-01
The recent progress in the application of nonlinear techniques to extend the frequency of laser sources has come from the joint progress in laser sources and in nonlinear materials. A brief summary of the progress in diode pumped solid state lasers is followed by an overview of progress in nonlinear frequency extension by harmonic generation and parametric processes. Improved nonlinear materials including bulk crystals, quasiphasematched interactions, guided wave devices, and quantum well intersubband studies are discussed with the idea of identifying areas of future progress in nonlinear materials and devices.
Scale-invariant nonlinear optics in gases
Heyl, C M; Miranda, M; Louisy, M; Kovacs, K; Tosa, V; Balogh, E; Varjú, K; L'Huillier, A; Couairon, A; Arnold, C L
2015-01-01
Nonlinear optical methods are becoming ubiquitous in many areas of modern photonics. They are, however, often limited to a certain range of input parameters, such as pulse energy and average power, since restrictions arise from, for example, parasitic nonlinear effects, damage problems and geometrical considerations. Here, we show that many nonlinear optics phenomena in gaseous media are scale-invariant if spatial coordinates, gas density and laser pulse energy are scaled appropriately. We develop a general scaling model for (3+1)-dimensional wave equations, demonstrating the invariant scaling of nonlinear pulse propagation in gases. Our model is numerically applied to high-order harmonic generation and filamentation as well as experimentally verified using the example of pulse post-compression via filamentation. Our results provide a simple recipe for up-or downscaling of nonlinear processes in gases with numerous applications in many areas of science.
Investigation of Optical Fibers for Nonlinear Optics.
1984-04-17
Northwestern University, 1970. Experience Dr. Harrington has 13 years of research experi- ence in the area of optical properties of solids . Since joining...dynamics, and optical properties of solids . 34 34I ANTONIO C. PASTOR, Member of the Technical Staff, Optical Physics Department, Hughes Research
Nonlinear Integrated Optical Waveguides in Chalcogenide Glasses
Institute of Scientific and Technical Information of China (English)
Yinlan; Ruan; Barry; Luther-Davies; Weitang; Li; Andrei; Rode; Marek; Samoc
2003-01-01
This paper reports on the study and measurement of the third order optical nonlinearity in bulk sulfide-based chalcogenide glasses; The fabrication process of the ultrafast laser deposited As-S-(Se)-based chalcogenide films and optical waveguides using two techniques: wet chemistry etching and plasma etching.
Forbidden second order optical nonlinearity of graphene
Cheng, J L; Sipe, J E
2016-01-01
We present a practical scheme to separate the contributions of the electric quadrupole-like and the magnetic dipole-like effects to the forbidden second order optical nonlinear response of graphene, and give analytic expressions for the second order optical conductivities, calculated from the independent particle approximation, with relaxation described in a phenomenological way. We predict strong second order nonlinear effects, including second harmonic generation, photon drag, and difference frequency generation. We discuss in detail the controllablity of these responses by tuning the chemical potential, where the interband optical transitions play a dominant role.
Nonlinear microstructured polymer optical fibres
DEFF Research Database (Denmark)
Frosz, Michael Henoch
. The combination of a small core size and zero-dispersion wavelength at the operating wavelength of widely available femtosecond Ti:sapphire lasers led to an extensive research in supercontinuum generation and other nonlinear effects in PCFs. It is crucial for the efficiency of many nonlinear mechanisms...... that the pump laser wavelength is close to the zero-dispersion wavelength and that the core size is small. Recently, work in fabricating PCFs from materials other than silica has intensified. One of the advantages of using alternative materials can be a higher inherent material nonlinearity, which...... to accurately obtain a small core size while maintaining small structural variations during fibre drawing. This talk will give a presentation of how the mPOFs are fabricated and the route to obtaining nonlinear effects in them....
Mesoscale Engineering of Nanocomposite Nonlinear Optical Materials
Energy Technology Data Exchange (ETDEWEB)
Afonso, C.N.; Feldman, L.C.; Gonella, F.; Haglund, R.F.; Luepke, G.; Magruder, R.H.; Mazzoldi, P.; Osborne, D.H.; Solis, J.; Zuhr, R.A.
1999-11-01
Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have ail been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to ask what is happening at nanoscale dimensions. Systems integration of complex nonlinear optical materials requires that the mesoscale materials science be well understood within the context of device structures. We discuss the effects of beam energy and energy density on quantum-dot size and spatial distribution, thermal conductivity, quantum-dot composition, crystallinity and defects - and, in turn, on the third-order optical susceptibility of the composite material. Examples from recent work in our laboratories are used to illustrate these effects.
Nonlinear dynamics in atom optics
Energy Technology Data Exchange (ETDEWEB)
Chen Wenyu; Dyrting, S.; Milburn, G.J. [Queensland Univ., St. Lucia, QLD (Australia). Dept. of Physics
1996-12-31
In this paper theoretical work on classical and quantum nonlinear dynamics of cold atoms is reported. The basic concepts in nonlinear dynamics are reviewed and then applied to the motion of atoms in time-dependent standing waves and to the atomic bouncer. The quantum dynamics for the cases of regular and chaotic classical dynamics is described. The effect of spontaneous emission and external noise is also discussed. 104 refs., 1 tab., 21 figs.
Nonlinear optical properties of metal nanoparticle composites for optical applications
Energy Technology Data Exchange (ETDEWEB)
Takeda, Y. E-mail: takeda.yoshihiko@nims.go.jp; Kishimoto, N
2003-05-01
Optical absorption and nonlinear optical response were investigated for nanoparticle composites in amorphous SiO{sub 2} fabricated by negative Ta ion implantation at 60 keV. X-ray photoelectron spectroscopy was used to identify Ta and the oxide formation in the matrix. Optical absorption clearly indicated a surface plasmon peak at 2.2 eV and the peak resulted from formation of nanoparticles embedded in the matrix. The measured absorption was compared with calculated ones, evaluated by Maxwell-Garnett theory. Nonlinear absorption was measured with a pump-probe method using a femtosecond laser system. The pumping laser transiently bleached the surface plasmon band and lead to the nonlinearity. The transient response recovered in several picoseconds and behaved in terms of electron dynamics in metallic nanoparticles. The Ta nanoparticle composite is one of the promising candidates for nonlinear optical materials with good thermal stability.
Optical rogue waves and soliton turbulence in nonlinear fibre optics
DEFF Research Database (Denmark)
Genty, G.; Dudley, J. M.; de Sterke, C. M.
2009-01-01
We examine optical rogue wave generation in nonlinear fibre propagation in terms of soliton turbulence. We show that higher-order dispersion is sufficient to generate localized rogue soliton structures, and Raman scattering effects are not required.......We examine optical rogue wave generation in nonlinear fibre propagation in terms of soliton turbulence. We show that higher-order dispersion is sufficient to generate localized rogue soliton structures, and Raman scattering effects are not required....
Zhao, Xingang; Yu, Guangtao; Huang, Xuri; Chen, Wei; Niu, Min
2013-12-01
Under high-level ab initio calculations, the geometrical structures and nonlinear optical properties of M@P₄ (M=Li, Na, K and Li₃O) and M@C₃H₆ (M=Li and Li₃O) were investigated; all were found to exhibit considerable first hyperpolarizabilities (18110, 1440, 22490, 50487, 2757 and 31776 au, respectively). The computational results revealed that when doping the (super)alkali atom M into the tetrahedral P₄ molecule, the original dual spherical aromaticity of the P₄ moiety is broken and new σ electron cloud is formed on the face of P₄ part interacting with the M atom. It was found that interaction of the (super)alkali atom with the σ electron cloud is a novel mode to produce diffuse excess electrons effectively to achieve a considerable β₀ value. Further, beyond the alkali atom, employing the superalkali unit can be a more effective approach to significantly enhance the first hyperpolarizability of the systems, due to the much lower vertical ionization potential. These results were further supported by the case of the (super)alkali atom interacting with the cyclopropane C₃H₆ molecule with its typical σ aromatic electron cloud. Moreover, the β₀ values of the M@P₄ series are nonmonotonic dependent on alkali atomic number, namely, 1440 au (M = Na) alkali atom and the interacting surface with the σ electron cloud in P4 is a crucial geometrical factor in determining their first hyperpolarizabilities. These intriguing findings will be advantageous for promoting the design of novel high-performance nonlinear optical materials.
Nonlinear optical properties of semiconductor nanocrystals
Ricard, Gianpiero Banfi Vittorio Degiorgio Daniel
1998-05-01
This review is devoted to the description of recent experimental results concerning the nonlinear optical properties of semiconductor-doped glasses SDGs with particular emphasis on the regime in which the energy of the incident photon is smaller than the energy gap. A considerable theoretical and experimental effort has been devoted in the last 10years to the fundamental aspects of quantumconfined structures, which have properties somewhat intermediate between the bulk crystals and atoms or molecules. From this point of view, SDGs represent an easily available test system, and optical techniques have been a major diagnostic tool. Luminescence and absorption spectroscopy were extensively used to characterize the electronic states. The experiments aimed at the measurement of the real and imaginary parts of the third-order optical susceptibility of SDGs below the bandgap are described in some detail, and the results obtained with different techniques are compared. Besides the intrinsic fast nonlinearity due to bound electrons, SDGs may present a larger but much slower nonlinearity due to the free carriers generated by two-photon absorption. This implies that experiments have to be properly designed for separation of the two effects. In this article we stress the importance of a detailed structural characterization of the samples. Knowledge of the volume fraction occupied by the nanocrystals is necessary in order to derive from the experimental data the intrinsic nonlinearity and to compare it with the bulk nonlinearity. We discuss recent experiments in which the dependence of the intrinsic nonlinearity on the crystal size is derived by performing, on the samples, measurements of the real part and imaginary part of the nonlinear optical susceptibility and measurements of crystal size and volume fraction. Structural characterization is of interest also for a better understanding of the physical processes underlying the growth of crystallites in SDGs. The average size of
Nonlinear optical model for strip plasmonic waveguides
DEFF Research Database (Denmark)
Lysenko, Oleg; Bache, Morten; Lavrinenko, Andrei
2016-01-01
This paper presents a theoretical model of nonlinear optical properties for strip plasmonic waveguides. The particular waveguides geometry that we investigate contains a gold core, adhesion layers, and silicon dioxide cladding. It is shown that the third-order susceptibility of the gold core...... significantly depends on the layer thickness and has the dominant contribution to the effective third-order susceptibility of the long-range plasmon polariton mode. This results in two nonlinear optical effects in plasmonic waveguides, which we experimentally observed and reported in [Opt. Lett. 41, 317 (2016......)]. The first effect is the nonlinear power saturation of the plasmonic mode, and the second effect is the spectral broadening of the plasmonic mode. Both nonlinear plasmonic effects can be used for practical applications and their appropriate model will be important for further developments in communication...
Enhancement of second-order nonlinear-optical signals by optical stimulation
Goodman, Aaron J
2015-01-01
Second-order nonlinear optical interactions such as sum- and difference-frequency generation are widely used for bioimaging and as selective probes of interfacial environments. However, inefficient nonlinear optical conversion often leads to poor signal-to-noise ratio and long signal acquisition times. Here, we demonstrate the dramatic enhancement of weak second-order nonlinear optical signals via stimulated sum- and difference-frequency generation. We present a conceptual framework to quantitatively describe the interaction and show that the process is highly sensitive to the relative optical phase of the stimulating field. To emphasize the utility of the technique, we demonstrate stimulated enhancement of second harmonic generation (SHG) from bovine collagen-I fibrils. Using a stimulating pulse fluence of only 3 nJ/cm2, we obtain an SHG enhancement >10^4 relative to the spontaneous signal. The stimulation enhancement is greatest in situations where spontaneous signals are the weakest - such as low laser pow...
Tunable nanowire nonlinear optical probe
Energy Technology Data Exchange (ETDEWEB)
Nakayama, Yuri; Pauzauskie, Peter J.; Radenovic, Aleksandra; Onorato, Robert M.; Saykally, Richard J.; Liphardt, Jan; Yang, Peidong
2008-02-18
One crucial challenge for subwavelength optics has been thedevelopment of a tunable source of coherent laser radiation for use inthe physical, information, and biological sciences that is stable at roomtemperature and physiological conditions. Current advanced near-fieldimaging techniques using fiber-optic scattering probes1,2 have alreadyachieved spatial resolution down to the 20-nm range. Recently reportedfar-field approaches for optical microscopy, including stimulatedemission depletion (STED)3, structured illumination4, and photoactivatedlocalization microscopy (PALM)5, have also enabled impressive,theoretically-unlimited spatial resolution of fluorescent biomolecularcomplexes. Previous work with laser tweezers6-8 has suggested the promiseof using optical traps to create novel spatial probes and sensors.Inorganic nanowires have diameters substantially below the wavelength ofvisible light and have unique electronic and optical properties9,10 thatmake them prime candidates for subwavelength laser and imagingtechnology. Here we report the development of an electrode-free,continuously-tunable coherent visible light source compatible withphysiological environments, from individual potassium niobate (KNbO3)nanowires. These wires exhibit efficient second harmonic generation(SHG), and act as frequency converters, allowing the local synthesis of awide range of colors via sum and difference frequency generation (SFG,DFG). We use this tunable nanometric light source to implement a novelform of subwavelength microscopy, in which an infrared (IR) laser is usedto optically trap and scan a nanowire over a sample, suggesting a widerange of potential applications in physics, chemistry, materials science,and biology.
Towards multimodal nonlinear optical tomography - experimental methodology
Vogler, N.; Medyukhina, A.; Latka, I.; Kemper, S.; Böhm, M.; Dietzek, B.; Popp, J.
2011-08-01
All-optical microspectroscopic and tomographic tools reveal great potential for clinical dermatologic diagnostics, i.e., investigation of human skin and skin diseases. While optical-coherence tomography has been complemented by two-photon fluorescence tomography and second-harmonic generation tomography, a joint study of various nonlinear optical microspectroscopies, i.e., application of the recently developed multimodal imaging approach, to sizable human-tissue samples has not been evaluated up to now. Here, we present such multimodal approach combining different nonlinear optical contrast mechanisms for imaging, namely two-photon excited fluorescence (TPF), second-harmonic generation (SHG), and coherent anti-Stokes Raman scattering (CARS) into a joint microscopic experiment. We show the potential of imaging large skin areas and discuss the information obtained in a case study comparing normal skin and keloid tissue.
Quantum nonlinear optics: nonlinear optics meets the quantum world (Conference Presentation)
Boyd, Robert W.
2016-02-01
This presentation first reviews the historical development of the field of nonlinear optics, starting from its inception in 1961. It then reviews some of its more recent developments, including especially how nonlinear optics has become a crucial tool for the developing field of quantum technologies. Fundamental quantum processes enabled by nonlinear optics, such as the creation of squeezed and entangled light states, are reviewed. We then illustrate these concepts by means of specific applications, such as the development of secure communication systems based on the quantum states of light.
Recent Issues on Nonlinear Effects in Optical Fibers
Institute of Scientific and Technical Information of China (English)
Takashi; Inoue; Osamu; Aso; Shu; Namiki
2003-01-01
This talk will discuss the types of optical signal degradation due to fiber nonlinearity and review recently invented fibers for suppressing the effects. It also introduces efficiency of highly nonlinear fibers and their applications to nonlinear signal processing.
Nonlinear microstructured polymer optical fibres
DEFF Research Database (Denmark)
Frosz, Michael Henoch
is potentially the case for microstructured polymer optical fibres (mPOFs). Another advantage is that polymer materials have a higher biocompatibility than silica, meaning that it is easier to bond certain types of biosensor materials to a polymer surface than to silica. As with silica PCFs, it is difficult...
Dispersive optical nonlinearities in an EIT-Rydberg medium
Stanojevic, Jovica; Bimbard, Erwan; Ourjoumtsev, Alexei; Grangier, Philippe
2013-01-01
We investigate dispersive optical nonlinearities that arise from Rydberg excitation blockade in cold Rydberg gases. We consider a two-photon transition scheme and study the non-linear response to a weak optical probe in presence of a strong control beam. For very low probe fields, the dominant nonlinearities are of the third order and they can be exactly evaluated in a steady state regime. In a more general case, the change in average atomic populations and coherences due to Rydberg interactions can be characterized by properly defined scaling parameters, which are generally complex numbers but in certain situations take the usual meaning of the number of atoms in a blockade sphere. They can be used in a simple "universal scaling" formula to determine the dispersive optical nonlinearity of the medium. We also develop a novel technique to account for the Rydberg interaction effects, by simplifying the treatment of nonlocal interaction terms, the so-called collisional integrals. We find algebraic relations that...
Localized Turing patterns in nonlinear optical cavities
Kozyreff, G.
2012-05-01
The subcritical Turing instability is studied in two classes of models for laser-driven nonlinear optical cavities. In the first class of models, the nonlinearity is purely absorptive, with arbitrary intensity-dependent losses. In the second class, the refractive index is real and is an arbitrary function of the intracavity intensity. Through a weakly nonlinear analysis, a Ginzburg-Landau equation with quintic nonlinearity is derived. Thus, the Maxwell curve, which marks the existence of localized patterns in parameter space, is determined. In the particular case of the Lugiato-Lefever model, the analysis is continued to seventh order, yielding a refined formula for the Maxwell curve and the theoretical curve is compared with recent numerical simulation by Gomila et al. [D. Gomila, A. Scroggie, W. Firth, Bifurcation structure of dissipative solitons, Physica D 227 (2007) 70-77.
Infiltrated microstructured fibers as tunable and nonlinear optical devices
DEFF Research Database (Denmark)
Rosberg, Christian Romer; Bennet, Francis; Neshev, Dragomir N.;
We study the light guiding properties of microstructured optical fibers infiltrated with nonlinear liquids and demonstrate their applicability for spatial beam control in novel type tunable and nonlinear optical devices....
Laser and nonlinear optical materials: SPIE volume 681
Energy Technology Data Exchange (ETDEWEB)
De Shazer, L.G.
1987-01-01
This book contains papers arranged under the following session headings: Nonlinear optical crystals; Laser host crystals; Electro-optic and magneto-optic materials; and Characterization of optical materials.
Nonlinear compression of optical solitons
Indian Academy of Sciences (India)
M N Vinoj; V C Kuriakose
2001-11-01
In this paper, we consider nonlinear Schrödinger (NLS) equations, both in the anomalous and normal dispersive regimes, which govern the propagation of a single ﬁeld in a ﬁber medium with phase modulation and ﬁbre gain (or loss). The integrability conditions are arrived from linear eigen value problem. The variable transformations which connect the integrable form of modiﬁed NLS equations are presented. We succeed in Hirota bilinearzing the equations and on solving, exact bright and dark soliton solutions are obtained. From the results, we show that the soliton is alive, i.e. pulse area can be conserved by the inclusion of gain (or loss) and phase modulation effects.
Nonlinear science an interactive Mathematica notebook
Campbell, David K; Tanury, Thomas A
2012-01-01
This interactive Mathematica(TM) notebook provides a ready-made tool by which users can undertake their own mathematical experiments and explore the behavior of non-linear systems, from chaos in low-dimensional maps and coupled ordinary differential equations to solitons and coherent structures in nonlinear partial differential equations and "intrisic localized modes" and "discrete breathers" in extended lattice systems.
Anisotropic and nonlinear optical waveguides
Someda, CG
1992-01-01
Dielectric optical waveguides have been investigated for more than two decades. In the last ten years they have had the unique position of being simultaneously the backbone of a very practical and fully developed technology, as well as an extremely exciting area of basic, forefront research. Existing waveguides can be divided into two sets: one consisting of waveguides which are already in practical use, and the second of those which are still at the laboratory stage of their evolution. This book is divided into two separate parts: the first dealing with anisotropic waveguides, an
Optical nonlinearities of small polarons in lithium niobate
Imlau, Mirco; Badorreck, Holger; Merschjann, Christoph
2015-12-01
An overview of optical nonlinearities of small bound polarons is given, which can occur in the congruently melting composition of LiNbO3. Such polarons decisively influence the linear and nonlinear optical performance of this material that is important for the field of optics and photonics. On the basis of an elementary phenomenological approach, the localization of carriers in a periodic lattice with intrinsic defects is introduced. It is applied to describe the binding energies of four electron and hole small polarons in LiNbO3: small free NbNb4 + polarons, small bound NbLi4 + polarons, small bound NbLi4 +:NbNb4 + bipolarons, and small bound O- hole polarons. For the understanding of their linear interaction with light, an optically induced transfer between nearest-neighboring polaronic sites is assumed. It reveals spectrally well separated optical absorption features in the visible and near-infrared spectral range, their small polaron peak energies and lineshapes. Nonlinear interaction of light is assigned to the optical formation of short-lived small polarons as a result of carrier excitation by means of band-to-band transitions. It is accompanied by the appearance of a transient absorption being spectrally constituted by the individual fingerprints of the small polarons involved. The relaxation dynamics of the transients is thermally activated and characterized phenomenologically by a stretched exponential behavior, according to incoherent 3D small polaron hopping between regular and defect sites of the crystal lattice. It is shown that the analysis of the dynamics is a useful tool for revealing the recombination processes between small polarons of different charge. Nonlinear interaction of small polarons with light furthermore results in changes of the index of refraction. Besides its causal relation to the transients via Kramers-Kronig relation, pronounced index changes may occur due to optically generated electric fields modulating the index of refraction
Second-order nonlinear optical microscopy of spider silk
Zhao, Yue; Hien, Khuat Thi Thu; Mizutani, Goro; Rutt, Harvey N.
2017-06-01
Asymmetric β-sheet protein structures in spider silk should induce nonlinear optical interaction such as second harmonic generation (SHG) which is experimentally observed for a radial line and dragline spider silk using an imaging femtosecond laser SHG microscope. By comparing different spider silks, we found that the SHG signal correlates with the existence of the protein β-sheets. Measurements of the polarization dependence of SHG from the dragline indicated that the β-sheet has a nonlinear response depending on the direction of the incident electric field. We propose a model of what orientation the β-sheet takes in spider silk.
Nonlinear Mixing in Optical Multicarrier Systems
Hameed, Mahmood Abdul
Although optical fiber has a vast spectral bandwidth, efficient use of this bandwidth is still important in order to meet the ever increased capacity demand of optical networks. In addition to wavelength division multiplexing, it is possible to partition multiple low-rate subcarriers into each high speed wavelength channel. Multicarrier systems not only ensure efficient use of optical and electrical components, but also tolerate transmission impairments. The purpose of this research is to understand the impact of mixing among subcarriers in Radio-Over-Fiber (RoF) and high speed optical transmission systems, and experimentally demonstrate techniques to minimize this impact. We also analyze impact of clipping and quantization on multicarrier signals and compare bandwidth efficiency of two popular multiplexing techniques, namely, orthogonal frequency division multiplexing (OFDM) and Nyquist modulation. For an OFDM-RoF system, we present a novel technique that minimizes the RF domain signal-signal beat interference (SSBI), relaxes the phase noise limit on the RF carrier, realizes the full potential of optical heterodyne-based RF carrier generation, and increases the performance-to-cost ratio of RoF systems. We demonstrate a RoF network that shares the same RF carrier for both downlink and uplink, avoiding the need of an additional RF oscillator in the customer unit. For multi-carrier optical transmission, we first experimentally compare performance degradations of coherent optical OFDM and single-carrier Nyquist pulse modulated systems in a nonlinear environment. We then experimentally evaluate SSBI compensation techniques in the presence of semiconductor optical amplifier (SOA) induced nonlinearities for a multicarrier optical system with direct detection. We show that SSBI contamination can be significantly reduced from the data signal when the carrier-to-signal power ratio is sufficiently low.
Bache, M; Bang, O; Zhou, B B; Moses, J; Wise, F W
2011-11-07
When ultrafast noncritical cascaded second-harmonic generation of energetic femtosecond pulses occur in a bulk lithium niobate crystal optical Cherenkov waves are formed in the near- to mid-IR. Numerical simulations show that the few-cycle solitons radiate Cherenkov (dispersive) waves in the λ = 2.2 - 4.5 μm range when pumping at λ₁ = 1.2 - 1.8 μm. The exact phase-matching point depends on the soliton wavelength, and we show that a simple longpass filter can separate the Cherenkov waves from the solitons. The Cherenkov waves are born few-cycle with an excellent Gaussian pulse shape, and the conversion efficiency is up to 25%. Thus, optical Cherenkov waves formed with cascaded nonlinearities could become an efficient source of energetic near- to mid-IR few-cycle pulses.
Quantum Information Processing using Nonlinear Optical Effects
DEFF Research Database (Denmark)
Andersen, Lasse Mejling
of the converted idler depends on the other pump. This allows for temporal-mode-multiplexing. When the effects of nonlinear phase modulation (NPM) are included, the phases of the natural input and output modes are changed, reducing the separability. These effects are to some degree mediated by pre......This PhD thesis treats applications of nonlinear optical effects for quantum information processing. The two main applications are four-wave mixing in the form of Bragg scattering (BS) for quantum-state-preserving frequency conversion, and sum-frequency generation (SFG) in second-order nonlinear...... to obtain a 100 % conversion efficiency is to use multiple stages of frequency conversion, but this setup suffers from the combined effects of NPM. This problem is circumvented by using asymmetrically pumped BS, where one pump is continuous wave. For this setup, NPM is found to only lead to linear phase...
Optically nonlinear Langmuir Blodgett films
Amiri, M A
2003-01-01
A series of novel amphiphilic molecules plus a new class of chevron-shaped materials, without aliphatic tails, were designed, synthesised and non-centrosymmetrically aligned by the Langmuir-Blodgett technique. Their LB films exhibited optical second-harmonic generation (SHG). The chevron-shaped molecules have a central cationic acceptor and two pi-bridged donor groups with an angle of ca. 120 deg between the charge-transfer axes of the D-pi-(A sup +)-pi-D unit. A monolayer LB film of a representative example, 1-butyl-2,6-bis[2- (4-dibutylaminophenyl)vinyl]pyridinium iodide, has an effective susceptibility, chi sup ( sup 2 sup ) sub e sub f sub f , of 120 pm V sup - sup 1 at 1064 nm, a thickness of 1.16 nm and an area in contact with the substrate of 0.91 nm sup 2 molecule sup - sup 1. The second-harmonic intensity (1.6 x 10 sup - sup 4 versus quartz) is similar to those of the extensively studied conventional amphiphilic hemicyanines but as a result of non-centrosymmetric alignment, without the need for long ...
Time-reversed wave mixing in nonlinear optics.
Zheng, Yuanlin; Ren, Huaijin; Wan, Wenjie; Chen, Xianfeng
2013-11-19
Time-reversal symmetry is important to optics. Optical processes can run in a forward or backward direction through time when such symmetry is preserved. In linear optics, a time-reversed process of laser emission can enable total absorption of coherent light fields inside an optical cavity of loss by time-reversing the original gain medium. Nonlinearity, however, can often destroy such symmetry in nonlinear optics, making it difficult to study time-reversal symmetry with nonlinear optical wave mixings. Here we demonstrate time-reversed wave mixings for optical second harmonic generation (SHG) and optical parametric amplification (OPA) by exploring this well-known but underappreciated symmetry in nonlinear optics. This allows us to observe the annihilation of coherent beams. Our study offers new avenues for flexible control in nonlinear optics and has potential applications in efficient wavelength conversion, all-optical computing.
Making of a nonlinear optical cavity
Martínez-Lorente, R; Esteban-Martín, A; García-Monreal, J; Roldán, E; Silva, F
2016-01-01
In the article we explain in detail how to build a photorefractive oscillator (PRO), which is a laser-pumped nonlinear optical cavity containing a photorefractive crystal. The specific PRO whose construction we describe systematically, is based on a Fabry-Perot optical cavity working in a non-degenerate four wave-mixing configuration. This particular PRO has the property that the generated beam exhibits laser-like phase invariance and, as an application, we show how a suitably modulated injected beam converts the output field from phase-invariant into phase-bistable. While the emphasis is made on the making of the experimental device and on the way measurements are implemented, some introduction to the photorefractive effect as well as to the necessary concepts of nonlinear dynamics are also given, so that the article is reasonably self-contained.
Impact of nonlinearities on fiber optic communications
2011-01-01
This book covers the recent progress in fiber-optic communication systems with a main focus on the impact of fiber nonlinearities on system performance. There has been significant progress in coherent communication systems in the past few years due to the advances in digital signal processing techniques. This has led to renewed interest in fiber linear and nonlinear impairments as well as techniques to mitigate them in the electrical domain. In this book, the reader will find all the important topics of fiber optic communication systems in one place, with in-depth coverage by the experts of each sub-topic. Pioneers from each of the sub-topics have been invited to contribute. Each chapter will have a section on fundamentals as well as reviews of literature and of recent developments. Readers will benefit from this approach since many of the conference proceedings and journal articles mainly focus on the authors’ research, without spending space on preliminaries.
Nonlinear optics of astaxanthin thin films
Esser, A.; Fisch, Herbert; Haas, Karl-Heinz; Haedicke, E.; Paust, J.; Schrof, Wolfgang; Ticktin, Anton
1993-02-01
Carotinoids exhibit large nonlinear optical properties due to their extended (pi) -electron system. Compared to other polyenes which show a broad distribution of conjugation lengths, carotinoids exhibit a well defined molecular structure, i.e. a well defined conjugation length. Therefore the carotinoid molecules can serve as model compounds to study the relationship between structure and nonlinear optical properties. In this paper the synthesis of four astaxanthins with C-numbers ranging from 30 to 60, their preparation into thin films, wavelength dispersive Third Harmonic Generation (THG) measurements and some molecular modelling calculations will be presented. Resonant (chi) (3) values reach 1.2(DOT)10-10 esu for C60 astaxanthin. In the nonresonant regime a figure of merit (chi) (3)/(alpha) of several 10-13 esu-cm is demonstrated.
Nonlinear optical studies of organic monolayers
Energy Technology Data Exchange (ETDEWEB)
Shen, Y.R.
1988-02-01
Second-order nonlinear optical effects are forbidden in a medium with inversion symmetry, but are necessarily allowed at a surface where the inversion summary is broken. They are often sufficiently strong so that a submonolayer perturbation of the surface can be readily detected. They can therefore be used as effective tools to study monolayers adsorbed at various interfaces. We discuss here a number of recent experiments in which optical second harmonic generation (SHG) and sum-frequency generation (SFG) are employed to probe and characterize organic monolayers. 15 refs., 5 figs.
Topological nature of nonlinear optical effects in solids
Morimoto, Takahiro; Nagaosa, Naoto
2015-01-01
There are a variety of nonlinear optical effects including higher harmonic generations, photovoltaic effects, and nonlinear Kerr rotations. They are realized by the strong light irradiation to materials that results in nonlinear polarizations in the electric field. These are of great importance in studying the physics of excited states of the system as well as for applications to optical devices and solar cells. Nonlinear properties of materials are usually described by the nonlinear suscepti...
Application of Novel Nonlinear Optical Materials to Optical Processing
Banerjee, Partha P.
1999-01-01
We describe wave mixing and interactions in nonlinear photorefractive polymers and disodium flourescein. Higher diffracted orders yielding forward phase conjugation can be generated in a two-wave mixing geometry in photorefractive polymers, and this higher order can be used for image edge enhancement and correlation. Four-wave mixing and phase conjugation is studied using nonlinear disodium floureschein, and the nature and properties of gratings written in this material are investigated.
Nonlinear inversion schemes for fluorescence optical tomography.
Freiberger, Manuel; Egger, Herbert; Scharfetter, Hermann
2010-11-01
Fluorescence optical tomography is a non-invasive imaging modality that employs the absorption and re-emission of light by fluorescent dyes. The aim is to reconstruct the fluorophore distribution in a body from measurements of light intensities at the boundary. Due to the diffusive nature of light propagation in tissue, fluorescence tomography is a nonlinear and severely ill-posed problem, and some sort of regularization is required for a stable solution. In this paper we investigate reconstruction methods based on Tikhonov regularization with nonlinear penalty terms, namely total-variation regularization and a levelset-type method using a nonlinear parameterization of the unknown function. Moreover, we use the full threedimensional nonlinear forward model, which arises from the governing system of partial differential equations. We discuss the numerical realization of the regularization schemes by Newtontype iterations, present some details of the discretization by finite element methods, and outline the efficient implementation of sensitivity systems via adjoint methods. As we will demonstrate in numerical tests, the proposed nonlinear methods provide better reconstructions than standard methods based on linearized forward models and linear penalty terms. We will additionally illustrate, that the careful discretization of the methods derived on the continuous level allows to obtain reliable, mesh independent reconstruction algorithms.
VARIANCE OF NONLINEAR PHASE NOISE IN FIBER-OPTIC SYSTEM
Directory of Open Access Journals (Sweden)
RANJU KANWAR
2013-04-01
Full Text Available In communication system, the noise process must be known, in order to compute the system performance. The nonlinear effects act as strong perturbation in long- haul system. This perturbation effects the signal, when interact with amplitude noise, and results in random motion of the phase of the signal. Based on the perturbation theory, the variance of nonlinear phase noise contaminated by both self- and cross-phase modulation, is derived analytically for phase-shift- keying system. Through this work, it is investigated that for longer transmission distance, 40-Gb/s systems are more sensitive to nonlinear phase noise as compared to 50-Gb/s systems. Also, when transmitting the data through the fiber optic link, bit errors are produced due to various effects such as noise from optical amplifiers and nonlinearity occurring in fiber. On the basis of the simulation results , we have compared the bit error rate based on 8-PSK with theoretical results, and result shows that in real time approach, the bit error rate is high for the same signal to noise ratio. MATLAB software is used to validate the analytical expressions for the variance of nonlinear phase noise.
Colloquium: Nonlinear Collective Interactions in Dense Plasmas
Shukla, P K
2010-01-01
The current understanding of some important collective processes in dense quantum plasmas is presented. After reviewing the basic properties of dense quantum plasmas with degenerate electrons, we present model equations (e.g. the quantum hydrodynamic and effective nonlinear Schr\\"odinger-Poisson equations) that describe collective nonlinear phenomena at nanoscales. The effects of the electron degeneracy arise due to Heisenberg's uncertainty principle and Pauli's exclusion principle for overlapping electron wave functions that result in a nonlinear quantum electron pressure and tunneling/diffusion of electrons through a nonlinear quantum Bohm potential. Since degenerate electrons have $1/2-$spin due to their Fermionic nature, there also appear a spin electron current and a spin force acting on the electrons due to the Bohr magnetization. The present nonlinear equations do not include strong electron correlations and electron-exchange interactions. The quantum effects caused by the electron degeneracy produce n...
Nonlinear Quantum Optics in Optomechanical Nanoscale Waveguides
Zoubi, Hashem
2016-01-01
We explore the possibility of achieving a significant nonlinear phase shift among photons propagating in nanoscale waveguides exploiting interactions among photons that are mediated by vibrational modes and induced through Stimulated Brillouin Scattering (SBS). We introduce a configuration that allows slowing down the photons by several orders of magnitude via SBS involving sound waves and two pump fields. We extract the conditions for maintaining vanishing amplitude gain or loss for slowly propagating photons while keeping the influence of thermal phonons to the minimum. The nonlinear phase among two counter-propagating photons can be used to realize a deterministic phase gate.
Soil-structure interaction including nonlinear soil
Gicev, Vlado
2008-01-01
There are two types of models of soil-structure system depending upon the rigidity of foundation: models with rigid and models with flexible foundation. Main features of the soil-structure interaction phenomenon: -wave scattering, -radiation damping, -reduction of the system frequencies. In this presentation, the influence of interaction on the development of nonlinear zones in the soil is studied.
Third-Order Nonlinear Optical Susceptibility of Indium Phosphide Nanocrystals
Institute of Scientific and Technical Information of China (English)
WANG Hong-Li; WANG Dong; CHEN Guang-De; LIU Hui
2007-01-01
InP nanocrystals synthesized by refluxing and annealing of organic solvent are determined from XRD measurements to have an average granularity of 25 nm. The nonlinear optical properties of the InP nanocrystals studied by using laser Z-scan technique with 50ps pulses at 532nm are found to reveal strong nonlinear optical properties and two-photon absorption phenomenon. Also, the nonlinear absorption coefficient, the nonlinear refractive index and the third-order nonlinear optical susceptibility are determined by experiments, in which the nonlinear refractive index is three orders of magnitude larger than that of bulk InP.
Institute of Scientific and Technical Information of China (English)
Peng Jin-Zhang; Yang Hong; Tang Yi
2009-01-01
By making use of the split-step Fourier method, this paper numerically simulates dynamical behaviors, including repulsion, fusion, scattering and spiraling of colliding (3+1)D spatiotemporal solitons in both the dispersive medium with cubic-quintic and the saturable medium. Careful comparison of the colliding behaviors in these two media is presented. Although the origin of the nonlinearities is different in these two media, the obtained results show that the dynamical behaviors are very similar. This presents additional evidence to support the supposition of universality of interactions between solitons.
DSP Approach to the Design of Nonlinear Optical Devices
Directory of Open Access Journals (Sweden)
Steve Blair
2005-06-01
Full Text Available Discrete-time signal processing (DSP tools have been used to analyze numerous optical filter configurations in order to optimize their linear response. In this paper, we propose a DSP approach to design nonlinear optical devices by treating the desired nonlinear response in the weak perturbation limit as a discrete-time filter. Optimized discrete-time filters can be designed and then mapped onto a specific optical architecture to obtain the desired nonlinear response. This approach is systematic and intuitive for the design of nonlinear optical devices. We demonstrate this approach by designing autoregressive (AR and autoregressive moving average (ARMA lattice filters to obtain a nonlinear phase shift response.
Nonlinear wave interactions in quantum magnetoplasmas
Shukla, P K; Marklund, M; Stenflo, L
2006-01-01
Nonlinear interactions involving electrostatic upper-hybrid (UH), ion-cyclotron (IC), lower-hybrid (LH), and Alfven waves in quantum magnetoplasmas are considered. For this purpose, the quantum hydrodynamical equations are used to derive the governing equations for nonlinearly coupled UH, IC, LH, and Alfven waves. The equations are then Fourier analyzed to obtain nonlinear dispersion relations, which admit both decay and modulational instabilities of the UH waves at quantum scales. The growth rates of the instabilities are presented. They can be useful in applications of our work to diagnostics in laboratory and astrophysical settings.
Quantum nonlinear optics with polar J-aggregates in microcavities
Herrera, Felipe; Pachon, Leonardo A; Saikin, Semion K; Aspuru-Guzik, Alán
2014-01-01
We show that an ensemble of organic dye molecules with permanent electric dipole moments embedded in a microcavity can lead to strong optical nonlinearities at the single photon level. The strong long-range electrostatic interaction between chromophores due to their permanent dipoles introduces the desired nonlinearity of the light-matter coupling in the microcavity. We obtain the absorption spectra of a weak probe field under the influence of strong exciton-photon coupling with the cavity field. Using realistic parameters, we demonstrate that a single cavity photon can significantly modify the absorptive and dispersive response of the medium to a probe photon at a different frequency. Finally, we show that the system is in the regime of cavity-induced transparency with a broad transparency window for dye dimers. We illustrate our findings using pseudoisocyanine chloride (PIC) J-aggregates in currently-available optical microcavities.
Nonlinear optical localization in embedded chalcogenide waveguide arrays
Directory of Open Access Journals (Sweden)
Mingshan Li
2014-05-01
Full Text Available We report the nonlinear optical localization in an embedded waveguide array fabricated in chalcogenide glass. The array, which consists of seven waveguides with circularly symmetric cross sections, is realized by ultrafast laser writing. Light propagation in the chalcogenide waveguide array is studied with near infrared laser pulses centered at 1040 nm. The peak intensity required for nonlinear localization for the 1-cm long waveguide array was 35.1 GW/cm2, using 10-nJ pulses with 300-fs pulse width, which is 70 times lower than that reported in fused silica waveguide arrays and with over 7 times shorter interaction distance. Results reported in this paper demonstrated that ultrafast laser writing is a viable tool to produce 3D all-optical switching waveguide circuits in chalcogenide glass.
Harmonic nanoparticles: noncentrosymmetric metal oxides for nonlinear optics
Rogov, Andrii; Mugnier, Yannick; Bonacina, Luigi
2015-03-01
The combination of nonlinear optics and nanotechnology is an extremely rich scientific domain yet widely unexplored. We present here a review of recent optical investigations on noncentrosymmetric oxide nanoparticles with a large {{χ }(2)} response, often referred to as harmonic nanoparticles (HNPs). HNPs feature a series of properties which distinguish them from other photonics nanoprobes (quantum dots, up-conversion nanoparticles, noble metal particles). HNPs emission is inherently nonlinear and based on the efficient generation of harmonics as opposed to fluorescence or surface plasmon scattering. In addition, the fully coherent signal emitted by HNPs together with their polarization sensitive response and absence of resonant interaction make them appealing for several applications ranging from multi-photon (infrared) microscopy and holography, to cell tracking and sensing.
Awasarmol, V. V.; Gaikwad, D. K.; Raut, S. D.; Pawar, P. P.
The mass attenuation coefficients (μm) for organic nonlinear optical materials measured at 122-1330 keV photon energies were investigated on the basis of mixture rule and compared with obtained values of WinXCOM program. It is observed that there is a good agreement between theoretical and experimental values of the samples. All samples were irradiated with six radioactive sources such as 57Co, 133Ba, 22Na, 137Cs, 54Mn and 60Co using transmission arrangement. Effective atomic and electron numbers or electron densities (Zeff and Neff), molar extinction coefficient (ε), mass energy absorption coefficient (μen/ρ) and effective atomic energy absorption cross section (σa,en) were determined experimentally and theoretically using the obtained μm values for investigated samples and graphs have been plotted. The graph shows that the variation of all samples decreases with increasing photon energy.
The Gouy phase shift in nonlinear interactions of waves
Lastzka, Nico; Schnabel, Roman
2007-06-01
We theoretically analyze the influence of the Gouy phase shift on the nonlinear interaction between waves of different frequencies. We focus on χ(2)interaction of optical fields, e.g. through birefringent crystals, and show that focussing, stronger than suggested by the Boyd-Kleinman factor, can further improve nonlinear processes. An increased value of 3.32 for the optimal focussing parameter for a single pass process is found. The new value builds on the compensation of the Gouy phase shift by a spatially varying, instead constant, wave vector phase mismatch. We analyze the single-ended, singly resonant standing wave nonlinear cavity and show that in this case the Gouy phase shift leads to an additional phase during backreflection. Our numerical simulations may explain ill-understood experimental observations in such devices.
Structure/property relationships in non-linear optical materials
Energy Technology Data Exchange (ETDEWEB)
Cole, J.M. [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)]|[Durham Univ. (United Kingdom); Howard, J.A.K. [Durham Univ. (United Kingdom); McIntyre, G.J. [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)
1997-04-01
The application of neutrons to the study of structure/property relationships in organic non-linear optical materials (NLOs) is described. In particular, charge-transfer effects and intermolecular interactions are investigated. Charge-transfer effects are studied by charge-density analysis and an example of one such investigation is given. The study of intermolecular interactions concentrates on the effects of hydrogen-bonding and an example is given of two structurally similar molecules with very disparate NLO properties, as a result of different types of hydrogen-bonding. (author). 3 refs.
Villanueva, Guillermo E; Jakubinek, Michael B; Simard, Benoit; Oton, Claudio J; Matres, Joaquín; Shao, Li-Yang; Pérez-Millán, Pere; Albert, Jacques
2011-06-01
Single-wall carbon nanotube deposition on the cladding of optical fibers has been carried out to fabricate an all-fiber nonlinear device. Two different nanotube deposition techniques were studied. The first consisted of repeatedly immersing the optical fiber into a nanotube supension, increasing the thickness of the coating in each step. The second deposition involved wrapping a thin film of nanotubes around the optical fiber. For both cases, interaction of transmitted light through the fiber core with the external coating was assisted by the cladding mode resonances of a tilted fiber Bragg grating. Ultrafast nonlinear effects of the nanotube-coated fiber were measured by means of a pump-probe pulses experiment. © 2011 Optical Society of America
Energy Technology Data Exchange (ETDEWEB)
Picozzi, A., E-mail: Antonio.Picozzi@u-bourgogne.fr [Laboratoire Interdisciplinaire Carnot de Bourgogne, Université de Bourgogne, CNRS-UMR 5027, Dijon (France); Garnier, J. [Laboratoire de Probabilités et Modèles Aléatoires and Laboratoire Jacques-Louis Lions, Université Paris VII, 75205 Paris Cedex 13 (France); Hansson, T. [Department of Information Engineering, Università di Brescia, Brescia 25123 (Italy); Suret, P.; Randoux, S. [Laboratoire de Physique des Lasers, Atomes et Molécules, CNRS, Université de Lille (France); Millot, G. [Laboratoire Interdisciplinaire Carnot de Bourgogne, Université de Bourgogne, CNRS-UMR 5027, Dijon (France); Christodoulides, D.N. [College of Optics/CREOL, University of Central Florida, Orlando, FL 32816 (United States)
2014-09-01
The nonlinear propagation of coherent optical fields has been extensively explored in the framework of nonlinear optics, while the linear propagation of incoherent fields has been widely studied in the framework of statistical optics. However, these two fundamental fields of optics have been mostly developed independently of each other, so that a satisfactory understanding of statistical nonlinear optics is still lacking. This article is aimed at reviewing a unified theoretical formulation of statistical nonlinear optics on the basis of the wave turbulence theory, which provides a nonequilibrium thermodynamic description of the system of incoherent nonlinear waves. We consider the nonlinear Schrödinger equation as a representative model accounting either for a nonlocal or a noninstantaneous nonlinearity, as well as higher-order dispersion effects. Depending on the amount of nonlocal (noninstantaneous) nonlinear interaction and the amount of inhomogeneous (nonstationary) statistics of the incoherent wave, different types of kinetic equations are derived and discussed. In the spatial domain, when the incoherent wave exhibits inhomogeneous statistical fluctuations, different forms of the (Hamiltonian) Vlasov equation are obtained depending on the amount of nonlocality. This Vlasov approach describes the processes of incoherent modulational instability and localized incoherent soliton structures. In the temporal domain, the causality property inherent to the response function leads to a kinetic formulation analogous to the weak Langmuir turbulence equation, which describes nonlocalized spectral incoherent solitons. In the presence of a highly noninstantaneous response, this formulation reduces to a family of singular integro-differential kinetic equations (e.g., Benjamin–Ono equation), which describe incoherent dispersive shock waves. Conversely, a non-stationary statistics leads to a (non-Hamiltonian) long-range Vlasov formulation, whose self-consistent potential
Photonics linear and nonlinear interactions of laser light and matter
Menzel, R
2007-01-01
This book covers the fundamental properties and the description of single photons and light beams, experimentally and theoretically. It explains the essentials of linear interactions and most nonlinear interactions between light and matter in both the transparent and absorbing cases. It also provides a basic understanding of modern quantum optics and lasers, as well as the principles of nonlinear optical spectroscopy. It is self-consistent and enriched by a large number of calculated illustrations, examples, and descriptive tables. Graduate students in physics and electrical engineering, as well as other sciences, will find this book a thorough introduction to the field, while for lecturers and scientists it is a rich source of useful information and a ready-to-hand reference. The new edition has been thoroughly expanded and revised in all sections
Bacteriorhodopsin: Tunable Optical Nonlinear Magnetic Response
Bovino, F A; Sibilia, C; Giardina, M; Váró, G; Gergely, C
2011-01-01
We report on a strong and tunable magnetic optical nonlinear response of Bacteriorhodopsin (BR) under "off resonance" femtosecond (fs) pulse excitation, by detecting the polarization map of the noncollinear second harmonic signal of an oriented BR film, as a function of the input beam power. BR is a light-driven proton pump with a unique photochemistry initiated by the all trans retinal chromophore embedded in the protein. An elegant application of this photonic molecular machine has been recently found in the new area of optogenetics, where genetic expression of BR in brain cells conferred a light responsivity to the cells enabling thus specific stimulation of neurons. The observed strong tunable magnetic nonlinear response of BR might trigger promising applications in the emerging area of pairing optogenetics and functional magnetic resonance imaging susceptible to provide an unprecedented complete functional mapping of neural circuits.
Enhancement of Second-Order Nonlinear-Optical Signals by Optical Stimulation
Goodman, A. J.; Tisdale, W. A.
2015-05-01
Second-order nonlinear optical interactions such as sum- and difference-frequency generation are widely used for bioimaging and as selective probes of interfacial environments. However, inefficient nonlinear optical conversion often leads to poor signal-to-noise ratio and long signal acquisition times. Here, we demonstrate the dramatic enhancement of weak second-order nonlinear optical signals via stimulated sum- and difference-frequency generation. We present a conceptual framework to quantitatively describe the interaction and show that the process is highly sensitive to the relative optical phase of the stimulating field. To emphasize the utility of the technique, we demonstrate stimulated enhancement of second harmonic generation (SHG) from bovine collagen-I fibrils. Using a stimulating pulse fluence of only 3 nJ /cm2 , we obtain an SHG enhancement >104 relative to the spontaneous signal. The stimulation enhancement is greatest in situations where spontaneous signals are the weakest—such as low laser power, small sample volume, and weak nonlinear susceptibility—emphasizing the potential for this technique to improve signal-to-noise ratios in biological imaging and interfacial spectroscopy.
Tunable Resonators for Nonlinear Modal Interactions
Ramini, Abdallah
2016-10-04
Understanding the various mechanisms of nonlinear mode coupling in micro and nano resonators has become an imminent necessity for their successful implementation in practical applications. However, consistent, repeatable, and flexible experimental procedures to produce nonlinear mode coupling are lacking, and hence research into well-controlled experimental conditions is crucial. Here, we demonstrate well-controlled and repeatable experiments to study nonlinear mode coupling among micro and nano beam resonators. Such experimental approach can be applied to other micro and nano structures to help study their nonlinear interactions and exploit them for higher sensitive and less noisy responses. Using electrothermal tuning and electrostatic excitation, we demonstrate three different kinds of nonlinear interactions among the first and third bending modes of vibrations of slightly curved beams (arches): two-one internal resonance, three-one internal resonance, and mode veering (near crossing). The experimental procedure is repeatable, highly flexible, do not require special or precise fabrication, and is conducted in air and at room temperature. This approach can be applied to other micro and nano structures, which come naturally curved due to fabrication imperfections, such as CNTs, and hence lays the foundation to deeply investigate the nonlinear mode coupling in these structures in a consistent way.
Tunable Resonators for Nonlinear Modal Interactions
Ramini, Abdallah H.; Hajjaj, Amal Z.; Younis, Mohammad I.
2016-10-01
Understanding the various mechanisms of nonlinear mode coupling in micro and nano resonators has become an imminent necessity for their successful implementation in practical applications. However, consistent, repeatable, and flexible experimental procedures to produce nonlinear mode coupling are lacking, and hence research into well-controlled experimental conditions is crucial. Here, we demonstrate well-controlled and repeatable experiments to study nonlinear mode coupling among micro and nano beam resonators. Such experimental approach can be applied to other micro and nano structures to help study their nonlinear interactions and exploit them for higher sensitive and less noisy responses. Using electrothermal tuning and electrostatic excitation, we demonstrate three different kinds of nonlinear interactions among the first and third bending modes of vibrations of slightly curved beams (arches): two-one internal resonance, three-one internal resonance, and mode veering (near crossing). The experimental procedure is repeatable, highly flexible, do not require special or precise fabrication, and is conducted in air and at room temperature. This approach can be applied to other micro and nano structures, which come naturally curved due to fabrication imperfections, such as CNTs, and hence lays the foundation to deeply investigate the nonlinear mode coupling in these structures in a consistent way.
Non-reciprocal nonlinear optic induced transparency and frequency conversion on a chip
Guo, Xiang; Jung, Hojoong; Tang, Hong X
2015-01-01
Developments in photonic chips have spurred photon based classical and quantum information processing, attributing to the high stability and scalability of integrated photonic devices [1, 2]. Optical nonlinearity [3] is indispensable in these complex photonic circuits, because it allows for classical and quantum light sources, all-optical switch, modulation, and non-reciprocity in ambient environments. It is commonly known that nonlinear interactions are often greatly enhanced in the microcavities [4]. However, the manifestations of coherent photon-photon interaction in a cavity, analogous to the electromagnetically induced transparency [5], have never been reported on an integrated platform. Here, we present an experimental demonstration of the coherent photon-photon interaction induced by second order optical nonlinearity (\\chi^{(2)} ) on an aluminum nitride photonic chip. The non-reciprocal nonlinear optic induced transparency is demonstrated as a result of the coherent interference between photons with di...
Nonlinear Quantum Optics in Artificially Structured Media
Helt, Lukas Gordon
This thesis presents an analysis of photon pairs generated via either spontaneous parametric downconversion or spontaneous four-wave mixing in channel waveguides as well as in microring resonators side-coupled to channel waveguides. The state of photons exiting a particular device is calculated within a general Hamiltonian formalism that simplifies the link between quantum nonlinear optics experiments and classical nonlinear optics experiments. This state contains information regarding photon pair production efficiency as well as modal and spectral correlations between the two photons, characterized by a two-dimensional spectral distribution function called the biphoton wave function. In the limit of a low probability of pair production, photon pair production efficiencies are cast into forms resembling corresponding well-known classical nonlinear optical frequency conversion efficiencies, making it easy to see what plays the role of a classical "seed" field in an un-seeded (quantum) process. This also allows photon pair production efficiencies to be calculated based on the results of classical nonlinear optical experiments. It is further calculated that, unless generated photons are collected over a very narrow frequency range, their generation efficiency does not scale the same way with device length in a channel waveguide, or resonance quality factor in a microring resonator, as might be expected from the corresponding classical frequency conversion efficiency. Although calculations do not include self- or cross-phase modulation, nor two-photon absorption or free-carrier absorption, it is calculated that their neglect is justified in the low pair production probability limit. Linear (scattering) loss is also neglected, though partially addressed in the final chapter of this thesis. Biphoton wave functions are calculated explicitly, such that their shape and orientation, including approximate analytic expressions for their widths, can easily be determined. This
Nonlinear optical properties of induced transmission filters.
Owens, Daniel T; Fuentes-Hernandez, Canek; Hales, Joel M; Perry, Joseph W; Kippelen, Bernard
2010-08-30
The nonlinear optical (NLO) properties of induced transmission filters (ITFs) based on Ag are experimentally determined using white light continuum pump-probe measurements. The experimental results are supported using simulations based on the matrix transfer method. The magnitude of the NLO response is shown to be 30 times that of an isolated Ag film of comparable thickness. The impacts of design variations on the linear and NLO response are simulated. It is shown that the design can be modified to enhance the NLO response of an ITF by a factor of 2 or more over a perfectly matched ITF structure.
Nonlinear Optics in AlGaAs on Insulator
DEFF Research Database (Denmark)
Pu, Minhao; Ottaviano, Luisa; Semenova, Elizaveta;
2016-01-01
AlGaAs on insulator is a powerful nonlinear platform sporting a high effective nonlinearity and the possibility to fabricate complex designs. We will present low loss waveguides enabling efficient optical signal processing and Kerr comb generation.......AlGaAs on insulator is a powerful nonlinear platform sporting a high effective nonlinearity and the possibility to fabricate complex designs. We will present low loss waveguides enabling efficient optical signal processing and Kerr comb generation....
Nonlinear waves in strongly interacting relativistic fluids
Fogaça, D A; Filho, L G Ferreira
2013-01-01
During the past decades the study of strongly interacting fluids experienced a tremendous progress. In the relativistic heavy ion accelerators, specially the RHIC and LHC colliders, it became possible to study not only fluids made of hadronic matter but also fluids of quarks and gluons. Part of the physics program of these machines is the observation of waves in this strongly interacting medium. From the theoretical point of view, these waves are often treated with li-nearized hydrodynamics. In this text we review the attempts to go beyond linearization. We show how to use the Reductive Perturbation Method to expand the equations of (ideal and viscous) relativistic hydrodynamics to obtain nonlinear wave equations. These nonlinear wave equations govern the evolution of energy density perturbations (in hot quark gluon plasma) or baryon density perturbations (in cold quark gluon plasma and nuclear matter). Different nonlinear wave equations, such as the breaking wave, Korteweg-de Vries and Burgers equations, are...
Nonlinear dynamics of interacting populations
Bazykin, Alexander D
1998-01-01
This book contains a systematic study of ecological communities of two or three interacting populations. Starting from the Lotka-Volterra system, various regulating factors are considered, such as rates of birth and death, predation and competition. The different factors can have a stabilizing or a destabilizing effect on the community, and their interplay leads to increasingly complicated behavior. Studying and understanding this path to greater dynamical complexity of ecological systems constitutes the backbone of this book. On the mathematical side, the tool of choice is the qualitative the
Optical Nonlinearities and Ultrafast Carrier Dynamics in Semiconductor Quantum Dots
Energy Technology Data Exchange (ETDEWEB)
Klimov, V.; McBranch, D.; Schwarz, C.
1998-08-10
Low-dimensional semiconductors have attracted great interest due to the potential for tailoring their linear and nonlinear optical properties over a wide-range. Semiconductor nanocrystals (NC's) represent a class of quasi-zero-dimensional objects or quantum dots. Due to quantum cordhement and a large surface-to-volume ratio, the linear and nonlinear optical properties, and the carrier dynamics in NC's are significantly different horn those in bulk materials. napping at surface states can lead to a fast depopulation of quantized states, accompanied by charge separation and generation of local fields which significantly modifies the nonlinear optical response in NC's. 3D carrier confinement also has a drastic effect on the energy relaxation dynamics. In strongly confined NC's, the energy-level spacing can greatly exceed typical phonon energies. This has been expected to significantly inhibit phonon-related mechanisms for energy losses, an effect referred to as a phonon bottleneck. It has been suggested recently that the phonon bottleneck in 3D-confined systems can be removed due to enhanced role of Auger-type interactions. In this paper we report femtosecond (fs) studies of ultrafast optical nonlinearities, and energy relaxation and trap ping dynamics in three types of quantum-dot systems: semiconductor NC/glass composites made by high temperature precipitation, ion-implanted NC's, and colloidal NC'S. Comparison of ultrafast data for different samples allows us to separate effects being intrinsic to quantum dots from those related to lattice imperfections and interface properties.
Enhanced Kerr electro-optic nonlinearity through cascaded Pockels effects
Li, Guang-Zhen; Jiang, Hao-Wei; Chen, Xian-Feng
2015-01-01
We demonstrated a large enhancement of Kerr electro-optic nonlinearity through cascaded Pockels effects in a domain inversion ferroelectric crystal. We designed a structure that can implement the cascaded Pockels effects and second-harmonic generation simultaneously. The energy coupling between the fundamental lights of different polarizations led to a large nonlinear phase shift, and thus an effective electro-optic nonlinear refractive index. The effective nonlinearity can be either positive or negative, causing the second-harmonic spectra to move towards the coupling center, which in turn, offered us a way to measure the effective electro-optic nonlinear refractive index. The corresponding enhanced Kerr electro-optic nonlinearity is more than three orders of magnitude higher than the intrinsic value. These results open a door to manipulate the nonlinear phase by applying external electric field instead of light intensity in noncentrosymmetric crystals.
Nonlinear Optical Properties of Carotenoid and Chlorophyll Harmonophores
Tokarz, Danielle Barbara
Information regarding the structure and function of living tissues and cells is instrumental to the advancement of cell biology and biophysics. Nonlinear optical microscopy can provide such information, but only certain biological structures generate nonlinear optical signals. Therefore, structural specificity can be achieved by introducing labels for nonlinear optical microscopy. Few studies exist in the literature about labels that facilitate harmonic generation, coined "harmonophores". This thesis consists of the first major investigation of harmonophores for third harmonic generation (THG) microscopy. Carotenoids and chlorophylls were investigated as potential harmonophores. Their nonlinear optical properties were studied by the THG ratio technique. In addition, a tunable refractometer was built in order to determine their second hyperpolarizability (gamma). At 830 nm excitation wavelength, carotenoids and chlorophylls were found to have large negative gamma values however, at 1028 nm, the sign of gamma reversed for carotenoids and remained negative for chlorophylls. Consequently, at 1028 nm wavelength, THG signal is canceled with mixtures of carotenoids and chlorophylls. Furthermore, when such molecules are covalently bonded as dyads or interact within photosynthetic pigment-protein complexes, it is found that additive effects with the gamma values still play a role, however, the overall gamma value is also influenced by the intra-pigment and inter-pigment interaction. The nonlinear optical properties of aggregates containing chlorophylls and carotenoids were the target of subsequent investigations. Carotenoid aggregates were imaged with polarization-dependent second harmonic generation and THG microscopy. Both techniques revealed crystallographic information pertaining to H and J aggregates and beta-carotene crystalline aggregates found in orange carrot. In order to demonstrate THG enhancement due to labeling, cultured cells were labeled with carotenoid
Third-order nonlinear optical characterization of side-chain copolymers
Norwood, Robert A.; Sounik, James R.; Popolo, J.; Holcomb, Douglas P.
1991-12-01
Third order nonlinear optical properties of side-chain methacrylate copolymers incorporating 4-amino-4'-nitrostilbene, 4-oxy-4'nitrostilbene, and functionalized silicon phthalocyanine chromophores are measured by picosecond degenerate four wave mixing at 598 nm. The nonresonant stilbene system exhibits a pulse limited ultrafast response, while the resonant phthalocyanine system has a large excited state nonlinearity. Comparison of silicon phthalocyanine copolymers with solubilized guest/host systems dispersed in polymethylmethacrylate illustrate the importance of aggregation and phthalocyanine ring interaction in determining the linear optical properties and the magnitude and speed of the nonlinear optical response.
Optical polarization based logic functions (XOR or XNOR) with nonlinear Gallium nitride nanoslab.
Bovino, F A; Larciprete, M C; Giardina, M; Belardini, A; Centini, M; Sibilia, C; Bertolotti, M; Passaseo, A; Tasco, V
2009-10-26
We present a scheme of XOR/XNOR logic gate, based on non phase-matched noncollinear second harmonic generation from a medium of suitable crystalline symmetry, Gallium nitride. The polarization of the noncollinear generated beam is a function of the polarization of both pump beams, thus we experimentally investigated all possible polarization combinations, evidencing that only some of them are allowed and that the nonlinear interaction of optical signals behaves as a polarization based XOR. The experimental results show the peculiarity of the nonlinear optical response associated with noncollinear excitation, and are explained using the expression for the effective second order optical nonlinearity in noncollinear scheme.
Nonlinear interactions for massive spin-2 fields
Schmidt-May, Angnis
2016-01-01
We give a basic introduction to ghost-free nonlinear theories involving massive spin-2 fields, focussing on bimetric theory. After motivating the construction of such models from field theoretical considerations, we review the linear theories for massive and massless spin-2 fluctuations propagating on maximally symmetric backgrounds. The structure of general nonlinear spin-2 interactions is explained before we specialise to the ghost-free case. We review the maximally symmetric solutions of bimetric theory, its mass spectrum and the parameter limit which brings the theory close to general relativity. Finally we discuss applications of bimetric theory to cosmology with particular emphasis on the role of the general relativity limit.
Ciattoni, Alessandro
2014-01-01
Strong nonlinear optical mechanisms operating in a miniaturized environment have a key role in photonics since they allow complex and versatile light manipulation within subwavelength devices. On the other hand, due to its two-dimensional planar geometry, graphene can easily be embedded within miniaturized structures and has fascinating linear and nonlinear optical properties arising from its relativistic electron dynamics. However, very few light steering graphene-based setups with a strong nonlinear behavior have been proposed since, due to its intrinsic planar localization, graphene nonlinearity has to be exploited through novel schemes not available in standard bulk nonlinear optics. Here we show that an active cavity hosting a graphene sheet, when tuned near its lasing threshold, is able to isolate the spatially localized graphene nonlinearity thus producing a very strong nonlinear device response with multi-valued features. The proposed strategy for exploiting graphene nonlinearity through its baring co...
Nonlinear optical field sensors in extreme electromagnetic and acoustic environments
Garzarella, Anthony; Wu, Dong Ho
2014-03-01
Sensors based on electro-optic (EO) and magneto-optic (MO) crystals measure external electric and magnetic fields through changes in birefringence which the fields induce on the nonlinear crystals. Due to their small size and all-dielectric structure, EO and MO sensors are ideal in environments involving very large electromagnetic powers. Conventional antennas and metallic probes not only present safety hazards, due to their metallic structure and the presence of large currents, but they can also perturb the very fields they intend to measure. In the case of railguns, the large electromagnetic signals are also accompanied by tremendous acoustic noise, which presents a noise background that the sensors must overcome. In this presentation, we describe extensive data obtained from fiber optic EO and MO sensors used in the railgun of the Naval Research Laboratory. Along with the field measurements obtained, we will describe the interactions between the acoustic noise and the nonlinear crystals (most notably, photoelastic effects), the noise equivalent fields they produce, and methods they could be suppressed through the optical and geometrical configurations of the sensor so that the signal to noise ratio can be maximized.
Directory of Open Access Journals (Sweden)
C. Torres-Torres
2012-01-01
Full Text Available We report the transmittance modulation of optical signals in a nanocomposite integrated by two different silver doped zinc oxide thin solid films. An ultrasonic spray pyrolysis approach was employed for the preparation of the samples. Measurements of the third-order nonlinear optical response at a nonresonant 532 nm wavelength of excitation were performed using a vectorial two-wave mixing. It seems that the separated contribution of the optical nonlinearity associated with each film noticeable differs in the resulting nonlinear effects with respect to the additive response exhibited by the bilayer system. An enhancement of the optical Kerr nonlinearity is predicted for prime number arrays of the studied nanoclusters in a two-wave interaction. We consider that the nanostructured morphology of the thin solid films originates a strong modification of the third-order optical phenomena exhibited by multilayer films based on zinc oxide.
Research of nonlinear optical properties of copper nanoparticles
Institute of Scientific and Technical Information of China (English)
L.Guo; Z.H.Wu; 等
1999-01-01
This research reports the preparation and characterization of copper nanoparticles modified by didecyl benzene sulfonate (DBS),The Cu nanoparticles' size was determined to be 40nm by transmission electron microscope(TEM).The X-ray photoelectron spectrometry(XPS) results show that there are interactions between the copper nanoparticles and DBS function group.The nonlinear optical properties were studied by the four-wave mixing method.The value of x(3)/α0 was found to be 6.9×10-11 esucm.
Nonlinear Optical Wave Equation for Micro- and Nano-Structured Media and Its Application
2013-03-01
distribution is unlimited. 3 Summary Major trends recently occurred in the modern physics and applications of nonlinear optics are closely linked with...interaction in an optically transparent nonmagnetic continuous medium is the subject area of the macroscopic electrodynamics [1,2]. For the majority of...activity worldwide in the area of linear and nonlinear nanophotonics. References. [1]. L. D. Landau and E. M. Lifshitz, Electrodynamics of
Molecular Optics Nonlinear Optical Processes in Organic and Polymeric Crystals and Films. Part 2
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
Integrated optic devices based on nonlinear optical polymers
van Tomme, Emmanuel; van Daele, Peter P.; Baets, Roel G.; Lagasse, Paul E.
1991-03-01
An examination is made of the state of the art of nonlinear optical polymeric materials in view of their potential advantages. It is shown that these organic materials have many attractive features compared to LiNbO3 and III-V semiconductors with regard to their use in integrated optic circuits, especially since the level of integration is ever increasing. Considering more specifically electro-optic devices, a description is given of some of the theoretical background and basic properties. These polymers have already demonstrated a very high and extremely fast electro-optic effect compared to LiNbO3. It is also shown how low-loss waveguides can be fabricated by using easy techniques such as direct UV bleaching. The performance of phase modulators, Mach-Zehnder interferometers, and 2 x 2 space switches built with such polymers is already very promising. The results described in this study indicate a rapid rate of progress made by this technology, and one can expect that polymers in general and NLO polymers in particular will play an increasingly important role in integrated optics.
Nonlinear Interaction of Waves in Geomaterials
Ostrovsky, L. A.
2009-05-01
Progress of 1990s - 2000s in studying vibroacoustic nonlinearities in geomaterials is largely related to experiments in resonance samples of rock and soils. It is now a common knowledge that many such materials are very strongly nonlinear, and they are characterized by hysteresis in the dependence between the stress and strain tensors, as well as by nonlinear relaxation ("slow time"). Elastic wave propagation in such media has many peculiarities; for example, third harmonic amplitude is a quadratic (not cubic as in classical solids) function of the main harmonic amplitude, and average wave velocity is linearly (not quadratically as usual) dependent on amplitude. The mechanisms of these peculiarities are related to complex structure of a material typically consisting of two phases: a hard matrix and relatively soft inclusions such as microcracks and grain contacts. Although most informative experimental results have been obtained in rock in the form of resonant bars, few theoretical models are yet available to describe and calculate waves interacting in such samples. In this presentation, a brief overview of structural vibroacoustic nonlinearities in rock is given first. Then, a simple but rather general approach to the description of wave interaction in solid resonators is developed based on accounting for resonance nonlinear perturbations which are cumulating from period to period. In particular, the similarity and the differences between traveling waves and counter-propagating waves are analyzed for materials with different stress-strain dependences. These data can be used for solving an inverse problem, i.e. characterizing nonlinear properties of a geomaterial by its measured vibroacoustic parameters. References: 1. L. Ostrovsky and P. Johnson, Riv. Nuovo Chimento, v. 24, 1-46, 2007 (a review); 2. L. Ostrovsky, J. Acoust. Soc. Amer., v. 116, 3348-3353, 2004.
Large nonlocal nonlinear optical response of castor oil
Souza, Rogério F.; Alencar, Márcio A. R. C.; Meneghetti, Mario R.; Hickmann, Jandir M.
2009-09-01
The nonlocal nonlinearity of castor oil was investigated using the Z-scan technique in the CW regime at 514 nm and in femtosecond regime at 810 nm. Large negative nonlinear refractive indexes of thermal origin, thermo-optical coefficients and degree of nonlocality were obtained for both laser excitation wavelengths. The results indicate that the electronic part of the nonlinear refractive index and nonlinear absorption were negligible. Our results suggest that castor oil is promising candidate as a nonlinear medium for several nonlocal optical applications, such as in spatial soliton propagation, as well as a dispersant agent in the measurement of absorptive properties of nanoparticles.
Optical bistability in nonlinear composites with coated ellipsoidal nanoparticles
Pinchuk, A
2003-01-01
Nonlinear composite structures show great promise for use in optical switching, signal processing, etc. We derive an effective nonlinear dielectric permittivity of composite structures where coated ellipsoidal nonlinear particles are imbedded in a linear host medium. The derived expression for the effective dielectric permittivity tensor follows the Clasius-Mossotti approximation. We observe conditions for the existence of the optical bistability effect in a coated ellipsoidal particle with a nonlinear core and a metallic shell. Our numerical results show stronger bistability effects in more dense suspensions of nonlinear heterogeneous ellipsoids.
Composite structures for the enhancement of nonlinear optical materials.
Neeves, A E; Birnboim, M H
1988-12-01
Calculations of the nonlinear optical behavior are developed for model composites consisting of nanospheres with a metallic core and a nonlinear shell suspended in a nonlinear medium. The concept for the enhancement of optical phase conjugation from all these nonlinear regions is that the optical field can be concentrated both inside and in the neighborhood of the metallic core, aided by surface-mediated plasmon resonance. Calculations for gold cores and aluminum cores indicate that phase-conjugate reflectivity enhancements of 10(8) may be possible.
Characterizaticr of Solid State Laser and Nonlinear Optical Materials.
1995-02-02
materials useful in the different methods for obtaining frequency agility: narrow line emitters with multiple lasing channels and nonlinear optical materials . In...codoped with two or more rare earth ions were studied and computers models developed to explain their spectral dynamics. The nonlinear optical materials investigated
A Photonic Basis for Deriving Nonlinear Optical Response
Andrews, David L.; Bradshaw, David S.
2009-01-01
Nonlinear optics is generally first presented as an extension of conventional optics. Typically the subject is introduced with reference to a classical oscillatory electric polarization, accommodating correction terms that become significant at high intensities. The material parameters that quantify the extent of the nonlinear response are cast as…
Nonlinear refractive index of optical crystals
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%.
High nonlinear optical anisotropy of urea nanofibers
Isakov, D.; de Matos Gomes, E.; Belsley, M.; Almeida, B.; Martins, A.; Neves, N.; Reis, R.
2010-07-01
Nanofibers consisting of the optically nonlinear organic molecule urea embedded in both poly(ethylene oxide) (PEO) and poly(vinyl alcohol) (PVA) polymers were produced by the electrospinning technique. The second-harmonic generation produced by aligned fiber mats of these materials displays a strong dependence on the polarization of the incident light. In PVA-urea nanofibers the effectiveness in generating of the second-harmonic light is as high as that of a pure urea powder with an average grain size of 110 μm. The results suggest that single crystalline urea nanofibers were achieved with a long-range crystalline order extending into the range of 2-4 μm with PVA as the host polymer.
Nonlinear optical effects in pure and N-doped semiconductors
Donlagic, N S
2000-01-01
the optical response of a one-dimensional n-doped two-band semiconductor whose conduction band has been linearized with respect to the two Fermi points. Due to the linearization it is possible to calculate the linear and nonlinear response functions of the interacting electron system exactly. These response functions are then used in order to determine the linear absorption spectrum and the time-integrated signal of a degenerated four-wave-mixing experiment. It is shown that the well-known features of the linear response can directly be related to features of the nonlinear experiments. For example, the exponent which describes the algebraic decay of the time-integrated four-wave-mixing signal is functionally dependent on the exponent of the algebraic singularity in the linear absorption spectrum reflecting the common origin of the different phenomena. Over the last decades, the nonlinear optical properties of condensed matter systems have been an attractive and fruitful field of research. While the linear res...
Optical bistability in a nonlinear-shell-coated metallic nanoparticle
Chen, Hongli; Zhang, Youming; Zhang, Baile; Gao, Lei
2016-01-01
We provide a self-consistent mean field approximation in the framework of Mie scattering theory to study the optical bistability of a metallic nanoparticle coated with a nonlinear shell. We demonstrate that the nanoparticle coated with a weakly nonlinear shell exhibits optical bistability in a broad range of incident optical intensity. This optical bistability critically relies on the geometry of the shell-coated nanoparticle, especially the fractional volume of the metallic core. The incident wavelength can also affect the optical bistability. Through an optimization-like process, we find a design with broader bistable region and lower threshold field by adjusting the size of the nonlinear shell, the fractional volume of the metallic core, and the incident wavelength. These results may find potential applications in optical bistable devices such as all-optical switches, optical transistors and optical memories. PMID:26907967
Laser And Nonlinear Optical Materials For Laser Remote Sensing
Barnes, Norman P.
2005-01-01
NASA remote sensing missions involving laser systems and their economic impact are outlined. Potential remote sensing missions include: green house gasses, tropospheric winds, ozone, water vapor, and ice cap thickness. Systems to perform these measurements use lanthanide series lasers and nonlinear devices including second harmonic generators and parametric oscillators. Demands these missions place on the laser and nonlinear optical materials are discussed from a materials point of view. Methods of designing new laser and nonlinear optical materials to meet these demands are presented.
Non-Linear Dynamics and Fundamental Interactions
Khanna, Faqir
2006-01-01
The book is directed to researchers and graduate students pursuing an advanced degree. It provides details of techniques directed towards solving problems in non-linear dynamics and chos that are, in general, not amenable to a perturbative treatment. The consideration of fundamental interactions is a prime example where non-perturbative techniques are needed. Extension of these techniques to finite temperature problems is considered. At present these ideas are primarily used in a perturbative context. However, non-perturbative techniques have been considered in some specific cases. Experts in the field on non-linear dynamics and chaos and fundamental interactions elaborate the techniques and provide a critical look at the present status and explore future directions that may be fruitful. The text of the main talks will be very useful to young graduate students who are starting their studies in these areas.
Strong electronic correlation effects in coherent multidimensional nonlinear optical spectroscopy.
Karadimitriou, M E; Kavousanaki, E G; Dani, K M; Fromer, N A; Perakis, I E
2011-05-12
We discuss a many-body theory of the coherent ultrafast nonlinear optical response of systems with a strongly correlated electronic ground state that responds unadiabatically to photoexcitation. We introduce a truncation of quantum kinetic density matrix equations of motion that does not rely on an expansion in terms of the interactions and thus applies to strongly correlated systems. For this we expand in terms of the optical field, separate out contributions to the time-evolved many-body state due to correlated and uncorrelated multiple optical transitions, and use "Hubbard operator" density matrices to describe the exact dynamics of the individual contributions within a subspace of strongly coupled states, including "pure dephasing". Our purpose is to develop a quantum mechanical tool capable of exploring how, by coherently photoexciting selected modes, one can trigger nonlinear dynamics of strongly coupled degrees of freedom. Such dynamics could lead to photoinduced phase transitions. We apply our theory to the nonlinear response of a two-dimensional electron gas (2DEG) in a magnetic field. We coherently photoexcite the two lowest Landau level (LL) excitations using three time-delayed optical pulses. We identify some striking temporal and spectral features due to dynamical coupling of the two LLs facilitated by inter-Landau-level magnetoplasmon and magnetoroton excitations and compare to three-pulse four-wave-mixing (FWM) experiments. We show that these features depend sensitively on the dynamics of four-particle correlations between an electron-hole pair and a magnetoplasmon/magnetoroton, reminiscent of exciton-exciton correlations in undoped semiconductors. Our results shed light into unexplored coherent dynamics and relaxation of the quantum Hall system (QHS) and can provide new insight into non-equilibrium co-operative phenomena in strongly correlated systems.
Optical limiter based on two-dimensional nonlinear photonic crystals
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.
Nonlinear super-resolution nano-optics and applications
Wei, Jingsong
2015-01-01
This book covers many advances in the subjects of nano-optics and nano photonics. The author describes the principle and technical schematics of common methods for breaking through the optical diffraction limit and focuses on realizing optical super-resolution with nonlinear effects of thin film materials. The applications of nonlinear optical super-resolution effects in nano-data storage, nanolithography, and nano-imaging are also presented. This book is useful to graduate students majoring in optics and nano science and also serves as a reference book for academic researchers, engineers, technical professionals in the fields of super-resolution optics and laser techniques, nano-optics and nano photonics, nano-data storage, nano imaging, micro/nanofabrication and nanolithography and nonlinear optics.
Dimensionality of InGaAs nonlinear optical response
Energy Technology Data Exchange (ETDEWEB)
Bolton, S.R. [Univ. of California, Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley National Lab., CA (United States). Materials Sciences Div.
1995-07-01
In this thesis the ultrafast optical properties of a series of InGaAs samples ranging from the two to the three dimensional limit are discussed. An optical system producing 150 fs continuum centered at 1.5 microns was built. Using this system, ultrafast pump-probe and four wave mixing experiments were performed. Carrier thermalization measurements reveal that screening of the Coulomb interaction is relatively unaffected by confinement, while Pauli blocking nonlinearities at the band edge are approximately twice as strong in two dimensions as in three. Carrier cooling via phonon emission is influenced by confinement due both to the change in electron distribution function and the reduction in electron phonon coupling. Purely coherent band edge effects, as measured by the AC Stark effect and four wave mixing, are found to be dominated by the changes in excitonic structure which take place with confinement.
Improved fiber nonlinearity mitigation in dispersion managed optical OFDM links
Tamilarasan, Ilavarasan; Saminathan, Brindha; Murugappan, Meenakshi
2017-02-01
Fiber nonlinearity is seen as a capacity limiting factor in OFDM based dispersion managed links since the Four Wave Mixing effects become enhanced due to the high PAPR. In this paper, the authors have compared the linear and nonlinear PAPR reduction techniques for fiber nonlinearity mitigation in OFDM based dispersion managed links. In the existing optical systems, linear transform techniques such as SLM and PTS have been implemented to reduce nonlinear effects. In the proposed study, superior performance of the L2-by-3 nonlinear transform technique is demonstrated for PAPR reduction to mitigate fiber nonlinearities. The performance evaluation is carried out by interfacing multiple simulators. The results of both linear and nonlinear transform techniques have been compared and the results show that nonlinear transform technique outperforms the linear transform in terms of nonlinearity mitigation and improved BER performance.
The linear and nonlinear optical effects of white light
Institute of Scientific and Technical Information of China (English)
QI XinYuan; LIU SiMin; GUO Ru; LU Yi; GAO YuanMei; LIU ZhaoHong; HUANG ChunFu; ZHANG XiaoHua; ZHU Nan; XU JingJun
2009-01-01
An overview of our research group's experimental and theoretical developments is provided on the linear and nonlinear optical effects of white light since 2003. Their work includes the experimental researches on the white light one-dimensional photovoltaic dark spatial solitons and the waveguides and directional couplers induced by them, the circular and elliptic white-light dark spatial solitons and the white-light photorefractive phase masks, two-dimensional white-light photonic lattices and the applications of the white-light dark spatial solitons in the digital image transmission field, the interaction between the two-dimensional white-light dark spatial solitons to enhance or to improve the correlateddegree of the white light through the interaction between the white-light beam and coherent dark spatial solitons, the interaction between the one-or two-dimensional white-light dark spatial solitons and the two-dimensional white-light photonic lattices, respectively. We also numerically simulate the interaction between two or more partially incoherent bright spatial solitons and the white bright spatial soliton pairs in the saturated logarithmic nonlinear medium. We have observed experimentally for the first time,the modulation instability of the coherent light and white light, respectively, in self-defocusing medium and so on.
The linear and nonlinear optical effects of white light
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
An overview of our research group’s experimental and theoretical developments is provided on the linear and nonlinear optical effects of white light since 2003. Their work includes the experimental researches on the white light one-dimensional photovoltaic dark spatial solitons and the waveguides and directional couplers induced by them, the circular and elliptic white-light dark spatial solitons and the white-light photorefractive phase masks, two-dimensional white-light photonic lattices and the applications of the white-light dark spatial solitons in the digital image transmission field, the interaction between the two-dimensional white-light dark spatial solitons to enhance or to improve the correlated degree of the white light through the interaction between the white-light beam and coherent dark spatial solitons, the interaction between the one- or two-dimensional white-light dark spatial solitons and the two-dimensional white-light photonic lattices, respectively. We also numerically simulate the interaction between two or more partially incoherent bright spatial solitons and the white bright spatial soliton pairs in the saturated logarithmic nonlinear medium. We have observed experimentally for the first time, the modulation instability of the coherent light and white light, respectively, in self-defocusing medium and so on.
Nonlinear optical response in doped conjugated polymers
Harigaya, K
1995-01-01
Exciton effects on conjugated polymers are investigated in soliton lattice states. We use the Su-Schrieffer-Heeger model with long-range Coulomb interactions. The Hartree-Fock (HF) approximation and the single-excitation configuration- interaction (single-CI) method are used to obtain optical absorption spectra. The third-harmonic generation (THG) at off-resonant frequencies is calculated as functions of the soliton concentration and the chain length of the polymer. The magnitude of the THG at the 10 percent doping increases by the factor about 10^2 from that of the neutral system. This is owing to the accumulation of the oscillator strengths at the lowest exciton with increasing the soliton concentration. The increase by the order two is common for several choices of Coulomb interaction strengths.
Nonlinear optical properties of Au/PVP composite thin films
Institute of Scientific and Technical Information of China (English)
Shen Hong; Cheng Bo-Lin; Lu Guo-Wei; Wang Wei-Tian; Guan Dong-Yi; Chen Zheng-Hao; Yang Guo-Zhen
2005-01-01
Colloidal Au and poly(vinylpyrrolidone) (PVP) composite thin films are fabricated by spin-coating method. Linear optical absorption measurements of the Au/PVP composite films indicate an absorption peak around 530 nm due to the surface plasmon resonance of gold nanoparticles. Nonlinear optical properties are studied using standard Z-scan technique, and experimental results show large optical nonlinearities of the Au/PVP composite films. A large value of films.
Denz, Cornelia; Simoni, Francesco
2009-03-01
Nonlinearities are becoming more and more important for a variety of applications in nanosciences, bio-medical sciences, information processing and photonics. For applications at the crossings of these fields, especially microscopic and nanoscopic imaging and manipulation, nonlinearities play a key role. They may range from simple nonlinear parameter changes up to applications in manipulating, controlling and structuring material by light, or the manipulation of light by light itself. It is this area between basic nonlinear optics and photonic applications that includes `hot' topics such as ultra-resolution optical microscopy, micro- and nanomanipulation and -structuring, or nanophotonics. This special issue contains contributions in this field, many of them from the International Conference on Nonlinear Microscopy and Optical Control held in conjunction with a network meeting of the ESF COST action MP0604 `Optical Micromanipulation by Nonlinear Nanophotonics', 19-22 February 2008, Münster, Germany. Throughout this special issue, basic investigations of material structuring by nonlinear light--matter interaction, light-induced control of nanoparticles, and novel nonlinear material investigation techniques, are presented, covering the basic field of optical manipulation and control. These papers are followed by impressive developments of optical tweezers. Nowadays, optical phase contrast tweezers, twin and especially multiple beam traps, develop particle control in a new dimension: particles can be arranged, sorted and identified with high throughput. One of the most prominent forthcoming applications of optical tweezers is in the field of microfluidics. The action of light on fluids will open new horizons in microfluidic manipulation and control. The field of optical manipulation and control is a very broad field that has developed in an impressive way, in a short time, in Europe with the installation of the MP0604 network. Top researchers from 19 countries are
Nonlinear Optical Materials for the Smart Filtering of Optical Radiation.
Dini, Danilo; Calvete, Mário J F; Hanack, Michael
2016-11-23
The control of luminous radiation has extremely important implications for modern and future technologies as well as in medicine. In this Review, we detail chemical structures and their relevant photophysical features for various groups of materials, including organic dyes such as metalloporphyrins and metallophthalocyanines (and derivatives), other common organic materials, mixed metal complexes and clusters, fullerenes, dendrimeric nanocomposites, polymeric materials (organic and/or inorganic), inorganic semiconductors, and other nanoscopic materials, utilized or potentially useful for the realization of devices able to filter in a smart way an external radiation. The concept of smart is referred to the characteristic of those materials that are capable to filter the radiation in a dynamic way without the need of an ancillary system for the activation of the required transmission change. In particular, this Review gives emphasis to the nonlinear optical properties of photoactive materials for the function of optical power limiting. All known mechanisms of optical limiting have been analyzed and discussed for the different types of materials.
Optical and Nonlinear Optical Response of Light Sensor Thin Films
Directory of Open Access Journals (Sweden)
S. Z. Weisz
2005-04-01
Full Text Available For potential ultrafast optical sensor application, both VO2 thin films andnanocomposite crystal-Si enriched SiO2 thin films grown on fused quartz substrates weresuccessfully prepared using pulsed laser deposition (PLD and RF co-sputteringtechniques. In photoluminescence (PL measurement c-Si/SiO2 film containsnanoparticles of crystal Si exhibits strong red emission with the band maximum rangingfrom 580 to 750 nm. With ultrashort pulsed laser excitation all films show extremelyintense and ultrafast nonlinear optical (NLO response. The recorded holography fromall these thin films in a degenerate-four-wave-mixing configuration shows extremelylarge third-order response. For VO2 thin films, an optically induced semiconductor-tometalphase transition (PT immediately occurred upon laser excitation. it accompanied.It turns out that the fast excited state dynamics was responsible to the induced PT. For c-Si/SiO2 film, its NLO response comes from the contribution of charge carriers created bylaser excitation in conduction band of the c-Si nanoparticles. It was verified byintroducing Eu3+ which is often used as a probe sensing the environment variations. Itturns out that the entire excited state dynamical process associated with the creation,movement and trapping of the charge carriers has a characteristic 500 ps duration.
Topology optimization of nonlinear optical devices
DEFF Research Database (Denmark)
Jensen, Jakob Søndergaard
2011-01-01
This paper considers the design of nonlinear photonic devices. The nonlinearity stems from a nonlinear material model with a permittivity that depends on the local time-averaged intensity of the electric field. A finite element model is developed for time-harmonic wave propagation and an incremen......This paper considers the design of nonlinear photonic devices. The nonlinearity stems from a nonlinear material model with a permittivity that depends on the local time-averaged intensity of the electric field. A finite element model is developed for time-harmonic wave propagation...
Nonlinear interactions between gravity waves and tides
Institute of Scientific and Technical Information of China (English)
LIU Xiao; XU JiYao; MA RuiPing
2007-01-01
In this study, we present the nonlinear interactions between gravity waves (GWs) and tides by using the 2D numerical model for the nonlinear propagation of GWs in the compressible atmosphere. During the propagation in the tidal background, GWs become instable in three regions, that is z = 75-85 km, z =90-110 km and z= 115-130 km. The vertical wavelength firstly varies gradually from the initial 12 km to 27 km. Then the newly generated longer waves are gradually compressed. The longer and shorter waves occur in the regions where GWs propagate in the reverse and the same direction of the horizontal mean wind respectively. In addition, GWs can propagate above the main breaking region (90-110 km). During GWs propagation, not only the mean wind is accelerated, but also the amplitude of tide is amplified. Especially, after GWs become instable, this amplified effect to the tidal amplitude is much obvious.
Nonlinear interactions between gravity waves and tides
Institute of Scientific and Technical Information of China (English)
2007-01-01
In this study, we present the nonlinear interactions between gravity waves (GWs) and tides by using the 2D numerical model for the nonlinear propagation of GWs in the compressible atmosphere. During the propagation in the tidal background, GWs become instable in three regions, that is z = 75―85 km, z = 90―110 km and z = 115―130 km. The vertical wavelength firstly varies gradually from the initial 12 km to 27 km. Then the newly generated longer waves are gradually compressed. The longer and shorter waves occur in the regions where GWs propagate in the reverse and the same direction of the hori-zontal mean wind respectively. In addition, GWs can propagate above the main breaking region (90—110 km). During GWs propagation, not only the mean wind is accelerated, but also the amplitude of tide is amplified. Especially, after GWs become instable, this amplified effect to the tidal amplitude is much obvious.
Nonlinear Electromagnetic Interactions in Energetic Materials
Wood, M A; Moore, D S
2016-01-01
We study the scattering of electromagnetic waves in anisotropic energetic materials. Nonlinear light-matter interactions in molecular crystals result in frequency-conversion and polarization changes. Applied electromagnetic fields of moderate intensity can induce these nonlinear effects without triggering chemical decomposition, offering a mechanism for non-ionizing identification of explosives. We use molecular dynamics simulations to compute such two-dimensional Raman spectra in the terahertz range for planar slabs made of PETN and ammonium nitrate. We discuss third-harmonic generation and polarization-conversion processes in such materials. These observed far-field spectral features of the reflected or transmitted light may serve as an alternative tool for stand-off explosive detection.
Nonlinear Optical Response of Conjugated Polymer to Electric Field
Institute of Scientific and Technical Information of China (English)
ZHOU Yu-fang; ZHUANG De-xin; CUI Bin
2005-01-01
The organic π-conjugated polymers are of major interest materials for the use in electro-optical and nonlinear optical devices. In this work, for a selected polyacetylene chain, the optical absorption spectra in UV/Vis regime as well as the linear polarizabilitiy and nonlinear hyperpolarizability are calculated by using quantum chemical ab initio and semiempirical methods. The relationship of its optical property to electric field is obtained. Some physical mechanism of electric field effect on molecular optical property is discussed by means of electron distribution and intramolecular charge transfer.
Nonlinear fiber applications for ultrafast all-optical signal processing
Kravtsov, Konstantin
In the present dissertation different aspects of all-optical signal processing, enabled by the use of nonlinear fibers, are studied. In particular, we focus on applications of a novel heavily GeO2-doped (HD) nonlinear fiber, that appears to be superior to many other types of nonlinear fibers because of its high nonlinearity and suitability for the use in nonlinear optical loop mirrors (NOLMs). Different functions, such as all-optical switching, thresholding, and wavelength conversion, are demonstrated with the HD fibers in the NOLM configuration. These basic functions are later used for realization of ultrafast time-domain demultiplexers, clock recovery, detectors of short pulses in stealth communications, and primitive elements for analog computations. Another important technology that benefits from the use of nonlinear fiber-based signal processing is optical code-division multiple access (CDMA). It is shown in both theory and experiment that all-optical thresholding is a unique way of improving existing detection methods for optical CDMA. Also, it is the way of implementation of true asynchronous optical spread-spectrum networks, which allows full realization of optical CDMA potential. Some aspects of quantum signal processing and manipulation of quantum states are also studied in this work. It is shown that propagation and collisions of Thirring solitons lead to a substantial squeezing of quantum states, which may find applications for generation of squeezed light.
Nonlinear and Dispersive Optical Pulse Propagation
Dijaili, Sol Peter
In this dissertation, there are basically four novel contributions to the field of picosecond pulse propagation and measurement. The first contribution is the temporal ABCD matrix which is an analog of the traditional ABCD ray matrices used in Gaussian beam propagation. The temporal ABCD matrix allows for the easy calculation of the effects of linear chirp or group velocity dispersion in the time domain. As with Gaussian beams in space, there also exists a complete Hermite-Gaussian basis in time whose propagation can be tracked with the temporal ABCD matrices. The second contribution is the timing synchronization between a colliding pulse mode-locked dye laser and a gain-switched Fabry-Perot type AlGaAs laser diode that has achieved less than 40 femtoseconds of relative timing jitter by using a pulsed optical phase lock loop (POPLL). The relative timing jitter was measured using the error voltage of the feedback loop. This method of measurement is accurate since the frequencies of all the timing fluctuations fall within the loop bandwidth. The novel element is a broad band optical cross-correlator that can resolve femtosecond time delay errors between two pulse trains. The third contribution is a novel dispersive technique of determining the nonlinear frequency sweep of a picosecond pulse with relatively good accuracy. All the measurements are made in the time domain and hence there is no time-bandwidth limitation to the accuracy. The fourth contribution is the first demonstration of cross -phase modulation in a semiconductor laser amplifier where a variable chirp was observed. A simple expression for the chirp imparted on a weak signal pulse by the action of a strong pump pulse is derived. A maximum frequency excursion of 16 GHz due to the cross-phase modulation was measured. A value of 5 was found for alpha _{xpm} which is a factor for characterizing the cross-phase modulation in a similar manner to the conventional linewidth enhancement factor, alpha.
Linear and nonlinear optical properties of chalcogenide microstructured optical fibers
Trolès, Johann; Brilland, Laurent; Caillaud, Celine; Renversez, Gilles; Mechin, David; Adam, Jean-Luc
2015-03-01
Chalcogenide glasses are known for their large transparency in the mid-infrared and their high linear refractive index (>2). They present also a high non-linear coefficient (n2), 100 to 1000 times larger than for silica, depending on the composition. we have developed a casting method to prepare the microstructured chalcogenide preform. This method allows optical losses as low as 0.4 dB/m at 1.55 µm and less than 0.05 dB/m in the mid IR. Various chalcogenide MOFs operating in the IR range has been fabricated in order to associate the high non-linear properties of these glasses and the original MOF properties. For example, small core fibers have been drawn to enhance the non linearities for telecom applications such as signal regeneration and generation of supercontinuum sources. On another hand, in the 3-12 µm window, single mode fibers and exposed core fibers have been realized for Gaussian beams propagation and sensors applications respectively.
Nonlinear optical properties of manganese porphyrin-incorporated PVC film
Directory of Open Access Journals (Sweden)
Jeong-Hyon Ha
2010-12-01
Full Text Available We measured thermally originated solid phase nonlinear optical properties of manganese porphyrin-incorporated PVC polymer film using CW low-power Z-scan and optical power limiting methods. The nonlinear refractive index (n2 of this porphyrin film is estimated to have a negative value of 7.2 ⅹ10-5 cm2/W at 632.8 nm and to be larger than that of ZnTPP in the Nafion film. The photodegradation effect common in the solution phase appears to be minor in this solid phase system. The large nonlinear effect is thought to limit the optical power due to the aperture effect.
Nonlinear optical microscopy for imaging thin films and surfaces
Energy Technology Data Exchange (ETDEWEB)
Smilowitz, L.B.; McBranch, D.W.; Robinson, J.M.
1995-03-01
We have used the inherent surface sensitivity of second harmonic generation to develop an instrument for nonlinear optical microscopy of surfaces and interfaces. We have demonstrated the use of several nonlinear optical responses for imaging thin films. The second harmonic response of a thin film of C{sub 60} has been used to image patterned films. Two photon absorption light induced fluorescence has been used to image patterned thin films of Rhodamine 6G. Applications of nonlinear optical microscopy include the imaging of charge injection and photoinduced charge transfer between layers in semiconductor heterojunction devices as well as across membranes in biological systems.
Advances in chemical physics modern nonlinear optics, pt.1
Rice, Stuart A
2009-01-01
Partial table of contents: Hyper-Rayleigh and Hyper-Raman Rotational and Vibrational Spectroscopy (T. Bancewicz & Z. Ożgo). Polarization Properties of Hyper-Rayleigh and Hyper-Raman Scatterings (M. Kozierowski). Fast Molecular Reorientation in Liquid Crystals Probed by Nonlinear Optics (J. Lalanne, et al.). Nonlinear Propagation of Laser Light of Different Polarizations (G. Rivoire). Nonlinear Magneto-Optics of Magnetically Ordered Crystals (R. Zawodny). Dynamical Questions in Quantum Optics (A. Shumovsky). Quantum Resonance Fluorescence from Mutually Correlated Atoms (Z. Fi
Towards Ultrafast Communications: Nonlinear Coupling Dynamics and Light-Semiconductor Interaction
Wang, W.
2007-01-01
This thesis deals with some specific problems concerning the processing of ultrashort optical pulses and their interaction with semiconductors. It includes the investigation of the ultrashort optical pulse propagation and coupling dynamics in the nonlinear coupled waveguide, and the coherent and in
Towards Ultrafast Communications: Nonlinear Coupling Dynamics and Light-Semiconductor Interaction
Wang, W.
2007-01-01
This thesis deals with some specific problems concerning the processing of ultrashort optical pulses and their interaction with semiconductors. It includes the investigation of the ultrashort optical pulse propagation and coupling dynamics in the nonlinear coupled waveguide, and the coherent and
Modeling and compensation of transmitter nonlinearity in coherent optical OFDM.
Amiralizadeh, Siamak; Nguyen, An T; Rusch, Leslie A
2015-10-05
We present a comprehensive study of nonlinear distortions from an optical OFDM transmitter. Nonlinearities are introduced by the combination of effects from the digital-to-analog converter (DAC), electrical power amplifier (PA) and optical modulator in the presence of high peak-to-average power ratio (PAPR). We introduce parameters to quantify the transmitter nonlinearity. High input backoff avoids OFDM signal compression from the PA, but incurs high penalties in power efficiency. At low input backoff, common PAPR reduction techniques are not effective in suppressing the PA nonlinear distortion. A bit error distribution investigation shows a technique combining nonlinear predistortion with PAPR mitigation could achieve good power efficiency by allowing low input backoff. We use training symbols to extract the transmitter nonlinear function. We show that piecewise linear interpolation (PLI) leads to an accurate transmitter nonlinearity characterization. We derive a semi-analytical solution for bit error rate (BER) that validates the PLI approximation accurately captures transmitter nonlinearity. The inverse of the PLI estimate of the nonlinear function is used as a predistorter to suppress transmitter nonlinearity. We investigate performance of the proposed scheme by Monte Carlo simulations. Our simulations show that when DAC resolution is more than 4 bits, BER below forward error correction limit of 3.8 × 10(-3) can be achieved by using predistortion with very low input power backoff for electrical PA and optical modulator.
Nonlinear coherent dynamics of an atom in an optical lattice
Argonov, V Y
2006-01-01
We consider a simple model of lossless interaction between a two-level single atom and a standing-wave single-mode laser field which creates a one-dimensional optical lattice. Internal dynamics of the atom is governed by the laser field which is treated to be classical with a large number of photons. Center-of-mass classical atomic motion is governed by the optical potential and the internal atomic degree of freedom. The resulting Hamilton-Schr\\"odinger equations of motion are a five-dimensional nonlinear dynamical system with two integrals of motion. The main focus of the paper is chaotic atomic motion that may be quantified strictly by positive values of the maximal Lyapunov exponent. It is shown that atom, depending on the value of its total energy, can either oscillate chaotically in a well of the optical potential or fly ballistically with weak chaotic oscillations of its momentum or wander in the optical lattice changing the direction of motion in a chaotic way. In the regime of chaotic wandering atomic...
Nonlinear photon-assisted tunneling transport in optical gap antennas.
Stolz, Arnaud; Berthelot, Johann; Mennemanteuil, Marie-Maxime; Colas des Francs, Gérard; Markey, Laurent; Meunier, Vincent; Bouhelier, Alexandre
2014-05-14
We introduce strongly coupled optical gap antennas to interface optical radiation with current-carrying electrons at the nanoscale. The transducer relies on the nonlinear optical and electrical properties of an optical gap antenna operating in the tunneling regime. We discuss the underlying physical mechanisms controlling the conversion involving d-band electrons and demonstrate that a simple two-wire optical antenna can provide advanced optoelectronic functionalities beyond tailoring the electromagnetic response of a single emitter. Interfacing an electronic command layer with a nanoscale optical device may thus be facilitated by the optical rectennas discussed here.
Dielectric Optical-Controllable Magnifying Lens by Nonlinear Negative Refraction
Cao, Jianjun; Shang, Ce; Zheng, Yuanlin; Feng, Yaming; Chen, Xianfeng; Liang, Xiaogan; Wan, Wenjie
2015-01-01
A simple optical lens plays an important role for exploring the microscopic world in science and technology by refracting light with tailored spatially varying refractive indices. Recent advancements in nanotechnology enable novel lenses, such as, superlens and hyperlens, with sub-wavelength resolution capabilities by specially designed materials’ refractive indices with meta-materials and transformation optics. However, these artificially nano- or micro-engineered lenses usually suffer high losses from metals and are highly demanding in fabrication. Here, we experimentally demonstrate, for the first time, a nonlinear dielectric magnifying lens using negative refraction by degenerate four-wave mixing in a plano-concave glass slide, obtaining magnified images. Moreover, we transform a nonlinear flat lens into a magnifying lens by introducing transformation optics into the nonlinear regime, achieving an all-optical controllable lensing effect through nonlinear wave mixing, which may have many potential applications in microscopy and imaging science. PMID:26149952
Dielectric Optical-Controlled Magnifying Lens by Nonlinear Negative Refraction
Cao, Jianjun; Zheng, Yuanlin; Chen, Xianfeng; Liang, Xiaogan; Wan, Wenjie
2014-01-01
A simple optical lens plays an important role for exploring the microscopic world in science and technology by refracting light with tailored spatially varying refractive index. Recent advancements in nanotechnology enable novel lenses, such as, superlens, hyperlens, Luneburg lens, with sub-wavelength resolution capabilities by specially designing materials' refractive indices with meta-materials and transformation optics. However, these artificially nano/micro engineered lenses usually suffer high losses from metals and are highly demanding in fabrication. Here we experimentally demonstrate for the first time a nonlinear dielectric magnifying lens using negative refraction by degenerate four-wave mixing in a plano-concave glass slide, obtaining magnified images. Moreover, we transform a nonlinear flat lens into a magnifying lens by introducing transformation optics into nonlinear regime, achieving an all-optical controllable lensing effect through nonlinear wave mixing, which may have many potential applicat...
Intra-Channel Nonlinear Effect on Optical PPM Pulse Transmission
Institute of Scientific and Technical Information of China (English)
Sun; Linghao; Jarmo; Takala
2003-01-01
PPM encoded Gaussian pulse sequence shows more immunity than non-PPM schemes on optical fiber intra-channel nonlinearity and demonstrated by a numerical study of IXPM and IFWM effects deploying on 100Gb/s single channelsystem.
Topological nature of nonlinear optical effects in solids.
Morimoto, Takahiro; Nagaosa, Naoto
2016-05-01
There are a variety of nonlinear optical effects including higher harmonic generations, photovoltaic effects, and nonlinear Kerr rotations. They are realized by strong light irradiation to materials that results in nonlinear polarizations in the electric field. These are of great importance in studying the physics of excited states of the system as well as for applications to optical devices and solar cells. Nonlinear properties of materials are usually described by nonlinear susceptibilities, which have complex expressions including many matrix elements and energy denominators. On the other hand, a nonequilibrium steady state under an electric field periodic in time has a concise description in terms of the Floquet bands of electrons dressed by photons. We show theoretically, using the Floquet formalism, that various nonlinear optical effects, such as the shift current in noncentrosymmetric materials, photovoltaic Hall response, and photo-induced change of order parameters under the continuous irradiation of monochromatic light, can be described in a unified fashion by topological quantities involving the Berry connection and Berry curvature. We found that vector fields defined with the Berry connections in the space of momentum and/or parameters govern the nonlinear responses. This topological view offers a route to designing nonlinear optical materials.
Merging Nonlinear Optics and Negative-Index Metamaterials
Popov, Alexander K
2011-01-01
The extraordinary properties of nonlinear optical propagation processes in double-domain positive/negative index metamaterials are reviewed. These processes include second harmonic generation, three- and four-wave frequency mixing, and optical parametric amplification. Striking contrasts with the properties of the counterparts in ordinary materials are shown. We also discuss the possibilities for compensating strong losses inherent to plasmonic metamaterials, which present a major obstacle in numerous exciting applications, and the possibilities for creation of unique ultracompact photonic devices such as data processing chips and nonlinear-optical sensors. Finally, we propose similar extraordinary three-wave mixing processes in crystals based on optical phonons with negative dispersion.
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.
Optical computation based on nonlinear total reflectional optical switch at the interface
Indian Academy of Sciences (India)
Jianqi Zhang; Huan Xu
2009-03-01
A new scheme of binary half adder and full adder is proposed. It realizes a kind of all-optical computation which is based on the polarization coding technique and the nonlinear total reflectional optical switches.
Ionic two photon states and optical nonlinearity in. pi. -conjugated polymers
Energy Technology Data Exchange (ETDEWEB)
Dixit, S.N. (Lawrence Livermore National Lab., CA (USA)); Guo, D.; Mazumdar, S. (Arizona Univ., Tucson, AZ (USA). Dept. of Physics)
1990-11-06
A microscopic mechanism of optical nonlinearity in {pi}-conjugated polymers is presented. It is shown that the bulk of the nonlinearity is determined by only two well defined channels, even though an infinite number of channels are possible in principle. The above conclusion is true for both short and long range Coulomb interactions. The complete frequency dependence of the third harmonic generation in both trans-polyacetylene and polydiacetylene are explained within the same theoretical picture. 19 refs., 4 figs.
New CMOS Compatible Platforms for Integrated Nonlinear Optical Signal Processing
Moss, D J
2014-01-01
Nonlinear photonic chips have succeeded in generating and processing signals all-optically with performance far superior to that possible electronically - particularly with respect to speed. Although silicon-on-insulator has been the leading platform for nonlinear optics, its high two-photon absorption at telecommunications wavelengths poses a fundamental limitation. This paper reviews some of the recent achievements in CMOS-compatible platforms for nonlinear optics, focusing on amorphous silicon and Hydex glass, highlighting their potential future impact as well as the challenges to achieving practical solutions for many key applications. These material systems have opened up many new capabilities such as on-chip optical frequency comb generation and ultrafast optical pulse generation and measurement.
Platforms for integrated nonlinear optics compatible with silicon integrated circuits
Moss, David J
2014-01-01
Nonlinear photonic chips are capable of generating and processing signals all-optically with performance far superior to that possible electronically - particularly with respect to speed. Although silicon has been the leading platform for nonlinear optics, its high two-photon absorption at telecommunications wavelengths poses a fundamental limitation. We review recent progress in CMOS-compatible platforms for nonlinear optics, focusing on Hydex glass and silicon nitride and briefly discuss the promising new platform of amorphous silicon. These material systems have opened up many new capabilities such as on-chip optical frequency comb generation, ultrafast optical pulse generation and measurement. We highlight their potential future impact as well as the challenges to achieving practical solutions for many key applications.
Phonon-assisted nonlinear optical processes in ultrashort-pulse pumped optical parametric amplifiers
Isaienko, Oleksandr; Robel, István
2016-03-01
Optically active phonon modes in ferroelectrics such as potassium titanyl phosphate (KTP) and potassium titanyl arsenate (KTA) in the ~7-20 THz range play an important role in applications of these materials in Raman lasing and terahertz wave generation. Previous studies with picosecond pulse excitation demonstrated that the interaction of pump pulses with phonons can lead to efficient stimulated Raman scattering (SRS) accompanying optical parametric oscillation or amplification processes (OPO/OPA), and to efficient polariton-phonon scattering. In this work, we investigate the behavior of infrared OPAs employing KTP or KTA crystals when pumped with ~800-nm ultrashort pulses of duration comparable to the oscillation period of the optical phonons. We demonstrate that under conditions of coherent impulsive Raman excitation of the phonons, when the effective χ(2) nonlinearity cannot be considered instantaneous, the parametrically amplified waves (most notably, signal) undergo significant spectral modulations leading to an overall redshift of the OPA output. The pump intensity dependence of the redshifted OPA output, the temporal evolution of the parametric gain, as well as the pump spectral modulations suggest the presence of coupling between the nonlinear optical polarizations PNL of the impulsively excited phonons and those of parametrically amplified waves.
Nonlinear optics response of semiconductor quantum wells under high magnetic fields
Energy Technology Data Exchange (ETDEWEB)
Chemla, D.S.
1993-07-01
Recent investigations on the nonlinear optical response of semiconductor quantum wells in a strong perpendicular magnetic field, H, are reviewed. After some introductory material the evolution of the linear optical properties of GaAs QW`s as a function of H is discussed; an examination is made of how the magneto-excitons (MX) extrapolate continuously between quasi-2D QW excitons (X) when H = 0, and pairs of Landau levels (LL) when H {yields} {infinity}. Next, femtosecond time resolved investigations of their nonlinear optical response are presented; the evolution of MX-MX interactions with increasing H is stressed. Finally, how, as the dimensionality is reduced by application of H, the number of scattering channels is limited and relaxation of electron-hole pairs is affected. How nonlinear optical spectroscopy can be exploited to access the relaxation of angular momentum within magneto-excitons is also discussed.
Lifetime of the Nonlinear Geometric Optics Approximation
DEFF Research Database (Denmark)
Binzer, Knud Andreas
The subject of the thesis is to study acertain approximation method for highly oscillatory solutions to nonlinear partial differential equations.......The subject of the thesis is to study acertain approximation method for highly oscillatory solutions to nonlinear partial differential equations....
Label-free imaging through nonlinear optical signals
Directory of Open Access Journals (Sweden)
Ling Tong
2011-06-01
Full Text Available Strong intrinsic nonlinear optical (NLO signals not only make nanostructures promising agents for bio-imaging, but also advance NLO microscopy for the study of interactions between nanomaterials and live cells. Single beam modalities such as multiphoton luminescence, second harmonic generation, and third harmonic generation provide a simple way to probe many types of nanostructures. As for more advanced modalities, photothermal heterodyne imaging provides improved detection sensitivity for smaller objects, and transient absorption microscopy provides structural information to distinguish metal from semiconducting carbon nanotubes, and eumelanin from pheomelanin. The four-wave mixing signal achieves chemical selectivity in the presence of either vibrational or electronic resonance, as used in coherent Raman scattering imaging of molecules and in electronically resonance enhanced four-wave mixing imaging of nanostructures.
Calculation of nonlinear optical properties of molecular clusters
Energy Technology Data Exchange (ETDEWEB)
Yartsev, V. M.; Marcano O, A. [Instituto Venezolano de Investigaciones Cientificas, Caracas (Venezuela)
2001-03-01
Effects of electronic correlation and electron-intramolecular vibration coupling on the non-linear optical properties are studied. The Hubbard Hamiltonian is used for explicit treatment of electronic correlation in molecular dimmer. The static polarizability and the static second hyper polarizability {gamma} are calculated and their dependences on the model parameters are analyzed. The role of interaction between ion-radical complexes is considered within the model of two parallel dimers. [Spanish] Se estudian los efectos de correlacion y el acoplamiento del electron con las vibraciones moleculares sobre las propiedades opticas no lineales de agregados moleculares. Se utiliza un hamiltoniano de tipo Hubbard para el tratamiento explicito de la correlacion electronica en un dimero molecular. Se calculan la polarizabilidad estatica {alpha} y la hiperpolarizabilidad de segundo orden {gamma} al igual que se analizan sus dependencias de los parametros del modelo. Se estudia ademas el papel de la interaccion entre complejos ino-radical dentro del modelo de dos dimeros paralelos.
Prediction of nonlinear optical properties of large organic molecules
Cardelino, Beatriz H.
1992-01-01
The preparation of materials with large nonlinear responses usually requires involved synthetic processes. Thus, it is very advantageous for materials scientists to have a means of predicting nonlinear optical properties. The prediction of nonlinear optical properties has to be addressed first at the molecular level and then as bulk material. For relatively large molecules, two types of calculations may be used, which are the sum-over-states and the finite-field approach. The finite-field method was selected for this research, because this approach is better suited for larger molecules.
Shocks, singularities and oscillations in nonlinear optics and fluid mechanics
Santo, Daniele; Lannes, David
2017-01-01
The book collects the most relevant results from the INdAM Workshop "Shocks, Singularities and Oscillations in Nonlinear Optics and Fluid Mechanics" held in Rome, September 14-18, 2015. The contributions discuss recent major advances in the study of nonlinear hyperbolic systems, addressing general theoretical issues such as symmetrizability, singularities, low regularity or dispersive perturbations. It also investigates several physical phenomena where such systems are relevant, such as nonlinear optics, shock theory (stability, relaxation) and fluid mechanics (boundary layers, water waves, Euler equations, geophysical flows, etc.). It is a valuable resource for researchers in these fields. .
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....
Delocalization of nonlinear optical responses in plasmonic nanoantennas
Viarbitskaya, Sviatlana; Cluzel, Benoit; Francs, Gérard Colas des; Bouhelier, Alexandre
2015-01-01
Remote excitation and emission of two-photon luminescence and second-harmonic generation are observed in micrometer long gold rod optical antennas upon local illumination with a tightly focused near-infrared femtosecond laser beam. We show that the nonlinear radiations can be emitted from the entire antenna and the measured far-field angular patterns bear the information regarding the nature and origins of the respective nonlinear processes. We demonstrate that the nonlinear responses are transported by the propagating surface plasmon at excitation frequency, enabling thereby polariton-mediated tailoring and design of nonlinear responses.
Nonlinear shallow ocean-wave soliton interactions on flat beaches.
Ablowitz, Mark J; Baldwin, Douglas E
2012-09-01
Ocean waves are complex and often turbulent. While most ocean-wave interactions are essentially linear, sometimes two or more waves interact in a nonlinear way. For example, two or more waves can interact and yield waves that are much taller than the sum of the original wave heights. Most of these shallow-water nonlinear interactions look like an X or a Y or two connected Ys; at other times, several lines appear on each side of the interaction region. It was thought that such nonlinear interactions are rare events: they are not. Here we report that such nonlinear interactions occur every day, close to low tide, on two flat beaches that are about 2000 km apart. These interactions are closely related to the analytic, soliton solutions of a widely studied multidimensional nonlinear wave equation. On a much larger scale, tsunami waves can merge in similar ways.
Nonlinear limits to the information capacity of optical fiber communications
Mitra, P P; Mitra, Partha P.; Stark, Jason B.
2000-01-01
The exponential growth in the rate at which information can be communicated through an optical fiber is a key element in the so called information revolution. However, like all exponential growth laws, there are physical limits to be considered. The nonlinear nature of the propagation of light in optical fiber has made these limits difficult to elucidate. Here we obtain basic insights into the limits to the information capacity of an optical fiber arising from these nonlinearities. The key simplification lies in relating the nonlinear channel to a linear channel with multiplicative noise, for which we are able to obtain analytical results. In fundamental distinction to the linear additive noise case, the capacity does not grow indefinitely with increasing signal power, but has a maximal value. The ideas presented here have broader implications for other nonlinear information channels, such as those involved in sensory transduction in neurobiology. These have been often examined using additive noise linear cha...
Ageing of the nonlinear optical susceptibility in soft matter
Energy Technology Data Exchange (ETDEWEB)
Ghofraniha, N [SMC-INFM-CNR, c/o Universita di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185, Rome (Italy); Conti, C [Research Centre ' Enrico Fermi' , Via Panisperna 89/A, 00184 Rome (Italy); Leonardo, R Di [SOFT-INFM-CNR, c/o Universita di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185, Rome (Italy); Ruzicka, B [SOFT-INFM-CNR, c/o Universita di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185, Rome (Italy); Ruocco, G [SOFT-INFM-CNR, c/o Universita di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185, Rome (Italy)
2007-05-23
We investigate the nonlinear optics response of a colloidal dispersion undergoing dynamics slowing down with age, by using Z-scan and dynamic light scattering measurements. We study the high optical nonlinearity of an organic dye (rhodamine B) dispersed in a water-clay (laponite) suspension. We consider different clay concentrations (2.0-2.6 wt%) experiencing dynamics arrest. We find that (i) the concentration dependent exponential growth of both mean relaxation time and nonlinear absorption coefficient can be individually scaled to a master curve and (ii) the scaling times are the same for the two physical quantities. These findings indicate that the optical nonlinear susceptibility exhibits the same ageing universal scaling behaviour, typical of disordered out of equilibrium systems.
Third Order Nonlinear Optical Effects in Conjugated Polymers
Halvorson, Craig Steven
Third order nonlinear optical effects in conjugated materials were studied using two different spectroscopic methods, third harmonic generation and two photon absorption. The third harmonic generation spectra of cis-polyacetylene, trans-polyacetylene, oriented trans-polyacetylene, three isomers of polyaniline, cis and trans-polyacetylene in polyvinyl butyral, polyheptdadiester, polyheptadiketone, and MEH-PPV/polyethylene blends were measured. The nonlinear optical susceptibility increases with structural order, and is enhanced by the presence of a degenerate ground state. The magnitude of the susceptibility reaches as high as 10^{-7} esu, which is sufficient for the creation of all-optical nonlinear devices. The two photon absorption spectrum of oriented transpolyacetylene was measured using nonlinear photothermal deflection. The spectrum reveals directly the Ag state at 1.1 eV in trans-polyacetylene, and reveals another Ag state at higher energy. The magnitude of the two photon absorption is large enough to rule out using trans-polyacetylene in serial all-optical nonlinear devices; all-optical devices made from conjugated polymers must be parallel, not serial. A new figure of merit for nonlinear devices was proposed.
Simple nonlinear interferometer-based all-optical thresholder and its applications for optical CDMA.
Kravtsov, Konstantin; Prucnal, Paul R; Bubnov, Mikhail M
2007-10-01
We present an experimental demonstration of an ultrafast all-optical thresholder based on a nonlinear Sagnac interferometer. The proposed design is intended for operation at very small nonlinear phase shifts. Therefore, it requires an in-loop nonlinearity lower than for the classical nonlinear loop mirror scheme. Only 15 meters of conventional (non-holey) silica-based fiber is used as a nonlinear element. The proposed thresholder is polarization insensitive and is good for multi-wavelength operation, meeting all the requirements for autocorrelation detection in various optical CDMA communication systems. The observed cubic transfer function is superior to the quadratic transfer function of second harmonic generation-based thresholders.
Conditional linear-optical measurement schemes generate effective photon nonlinearities
Lapaire, G G; Dowling, J P; Sipe, J E; Dowling, Jonathan P.
2003-01-01
We provide a general approach for the analysis of optical state evolution under conditional measurement schemes, and identify the necessary and sufficient conditions for such schemes to simulate unitary evolution on the freely propagating modes. If such unitary evolution holds, an effective photon nonlinearity can be identified. Our analysis extends to conditional measurement schemes more general than those based solely on linear optics.
Chemical studies on the nonlinear optics of coordina- tion compounds
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The exploration of molecule-based nonlinear optical (NLO) materials at the molecular level is one of the novel areas developed recently from the viewpoint of chemistry. This review summarizes some of our recent researches on new NLO materials based on coordination compounds, which may have potential applications in optical devices.
Ultra-Fast Optical Signal Processing in Nonlinear Silicon Waveguides
DEFF Research Database (Denmark)
Oxenløwe, Leif Katsuo; Galili, Michael; Pu, Minhao;
2011-01-01
We describe recent demonstrations of exploiting highly nonlinear silicon nanowires for processing Tbit/s optical data signals. We perform demultiplexing and optical waveform sampling of 1.28 Tbit/s and wavelength conversion of 640 Gbit/s data signals....
Nonlinear fiber-optic strain sensor based on four-wave mixing in microstructured optical fiber
DEFF Research Database (Denmark)
Gu, Bobo; Yuan, Scott Wu; Frosz, Michael H.
2012-01-01
We demonstrate a nonlinear fiber-optic strain sensor, which uses the shifts of four-wave mixing Stokes and anti-Stokes peaks caused by the strain-induced changes in the structure and refractive index of a microstructured optical fiber. The sensor thus uses the inherent nonlinearity of the fiber...
Li, Bing-Xuan; Wei, Yong; Huang, Cheng-Hui; Zhuang, Feng-Jiang; Zhang, Ge; Guo, Guo-Cong
2014-01-01
In the present paper the authors report a research on testing the nonlinear optical performance of optical materials in visible and infrared band. Based on the second order nonlinear optic principle and the photoelectric signal detection technology, the authors have proposed a new testing scheme in which a infrared OPO laser and a method for separating the beams arising from frequency matching and the light produced by other optical effects were used. The OPO laser is adopted as light source to avoid the error of measurement caused by absorption because the double frequency signal of the material is in the transmittance band Our research work includes testing system composition, operational principle and experimental method. The experimental results of KTP, KDP, AGS tested by this method were presented. In the experiment several new infrared non-linear materials were found. This method possesses the merits of good stability and reliability, high sensitivity, simple operation and good reproducibility, which can effectively make qualitative and semi-quantitative test for optical material's nonlinear optical properties from visible to infrared. This work provides an important test -method for the research on second order nonlinear optical materials in visible, infrared and ultraviolet bands.
Cai, Wenshan
2016-09-01
Metamaterials have offered not only the unprecedented opportunity to generate unconventional electromagnetic properties that are not found in nature, but also the exciting potential to create customized nonlinear media with tailored high-order effects. Two particularly compelling directions of current interests are active metamaterials, where the optical properties can be purposely manipulated by external stimuli, and nonlinear metamaterials, which enable intensity-dependent frequency conversion of light. By exploring the interaction of these two directions, we leverage the electrical and optical functions simultaneously supported in nanostructured metals and demonstrate electrically-controlled nonlinear processes from photonic metamaterials. We show that a variety of nonlinear optical phenomena, including the wave mixing and the optical rectification, can be purposely modulated by applied voltage signals. In addition, electrically-induced and voltage-controlled nonlinear effects facilitate us to demonstrate the backward phase matching in a negative index material, a long standing prediction in nonlinear metamaterials. Other results to be covered in this talk include photon-drag effect in plasmonic metamaterials and ion-assisted nonlinear effects from metamaterials in electrolytes. Our results reveal a grand opportunity to exploit optical metamaterials as self-contained, dynamic electrooptic systems with intrinsically embedded electrical functions and optical nonlinearities. Reference: L. Kang, Y. Cui, S. Lan, S. P. Rodrigues, M. L. Brongersma, and W. Cai, Nature Communications, 5, 4680 (2014). S. P. Rodrigues and W.Cai, Nature Nanotechnology, 10, 387 (2015). S. Lan, L. Kang, D. T. Schoen, S. P. Rodrigues, Y. Cui, M. L. Brongersma, and W. Cai, Nature Materials, 14, 807 (2015).
Liu, Feng
This dissertation involves the design, synthesis and characterization of second order nonlinear optical chromophores for electro-optic applications. The design concept, that poling efficiency and macroscopic nonlinearities can be improved by modifying a chromophore's shape, has been explored. Chapter 1 gives an introduction into theoretical background of nonlinear optics and electro-optic phenomenon in organic molecules and poled polymers. Chapter 2 involves the design and synthesis of GLD-2 and GLD-3 chromophores, both with bulky substituents on the ring-fused bridge. The optical studies and HRS measurement show that the two alkyl groups on the bridge blueshift the lambdamax in chloroform by 20 nm and decrease the beta values. DSC and TGA thermal analysis show Td of GLD-2 and GLD-3 over 240°C. The maximum achievable r33 of GLD-2/PMMA is 61 pm/V, compared to the 92.4 pm/V of GLD-1/PMMA. But GLD-2/APC shows r33 of 45.2pm/V, higher than GLD-1/APC due to the improved compatibility with APC. The optical loss of 13 wt% GLD-2/PMMA at 1.55mum is 1.4 dB compared to the 2.3 dB of 17 wt% GLD-1/PMMA. Optical loss studies prove that adding two bulky substituents on bridge help attenuate electrostatic interactions. GLD-3 show deteriorated solubility in common used organic solvents, probably due to the combination of two TBDMS and two lengthy alkyl groups. Chapter 3 presents synthesis of thiophene-based chromophores with variously positioned TBDMS groups. The optical studies of these chromophores show one TBDMSO substitution on the thiophene bridge yields little influence on the lambda max in chloroform. FTCDS chromophore with two TBDMS groups, one on donor and one on thiophene bridge, shows to be the best structure with regards the thermal stability and achievable maximum EO coefficient value, 65.9 pm/V, at only 24 wt% loading density at 1.3 mum. Chapter 4 deals with three novel bridges for NLO chromophores. Synthetic methodologies of the diketone precursor of rigidified
Lavdas, Spyros; You, Jie; Osgood, Richard M.; Panoiu, Nicolae C.
2015-08-01
We present recent results pertaining to pulse reshaping and optical signal processing using optical nonlinearities of silicon-based tapered photonic wires and photonic crystal waveguides. In particular, we show how nonlinearity and dispersion engineering of tapered photonic wires can be employed to generate optical similaritons and achieve more than 10× pulse compression. We also discuss the properties of four-wave mixing pulse amplification and frequency conversion efficiency in long-period Bragg waveguides and photonic crystal waveguides. Finally, the influence of linear and nonlinear optical effects on the transmission bit-error rate in uniform photonic wires and photonic crystal waveguides made of silicon is discussed.
Hofstadter butterflies in nonlinear Harper lattices, and their optical realizations
Energy Technology Data Exchange (ETDEWEB)
Manela, Ofer; Segev, Mordechai [Department of Physics and Solid State Institute, Technion, Haifa 32000 (Israel); Christodoulides, Demetrios N [College of Optics/CREOL, University of Central Florida, FL 32816-2700 (United States); Kip, Detlef, E-mail: msegev@tx.technion.ac.i [Department of Electrical Engineering, Helmut Schmidt University, 22043 Hamburg (Germany)
2010-05-15
The ubiquitous Hofstadter butterfly describes a variety of systems characterized by incommensurable periodicities, ranging from Bloch electrons in magnetic fields and the quantum Hall effect to cold atoms in optical lattices and more. Here, we introduce nonlinearity into the underlying (Harper) model and study the nonlinear spectra and the corresponding extended eigenmodes of nonlinear quasiperiodic systems. We show that the spectra of the nonlinear eigenmodes form deformed versions of the Hofstadter butterfly and demonstrate that the modes can be classified into two families: nonlinear modes that are a 'continuation' of the linear modes of the system and new nonlinear modes that have no counterparts in the linear spectrum. Finally, we propose an optical realization of the linear and nonlinear Harper models in transversely modulated waveguide arrays, where these Hofstadter butterflies can be observed. This work is relevant to a variety of other branches of physics beyond optics, such as disorder-induced localization in ultracold bosonic gases, localization transition processes in disordered lattices, and more.
The optical nonlinearity of gold nanoparticles prepared by bioreduction method
Balbuena Ortega, A.; Arroyo Carrasco, M. L.; Gayou, V. L.; Orduña Díaz, A.; Delgado Macuil, R.; Rojas López, Marlon
2013-11-01
Nonlinear optical and electronic properties of nanosized metal particles have drawn considerable attention because of their strong and size-dependent plasmon resonance absorption. In a metal nanoparticle system such as gold dispersed in a transparent matrix, an absorption peak due to surface plasmon resonance is usually observed in the visible spectral region. Metal nanoparticles are of special interest as nonlinear materials for optical switching and computing because of their relatively large third-order nonlinearity (χ3) and ultrafast response time. The purpose of this study was to analyze the nonlinear optical properties of biosynthesized gold nanoparticles. The samples were prepared by biosynthesis method using yeast extract as reducing agent and the nonlinear optical properties of the nanoparticles were investigated using a single beam Z-scan technique with a beam power of 20 mW and operated at wavelength of 514 nm. The reaction between metal ions and yeast extracts were monitored by UV-visible spectra of Au nanoparticles in aqueous solution with different pH (3-6). The surface plasmon peak position was shifted from 528 nm to 573 nm, according to of pH variation 4 to 6. The average particle size was calculated by the absorption peak position using the Fernig method, from 42 to 103 nm. The z-scan curves showed a negative nonlocal nonlinear refractive index with a magnitude dependent on the nanoparticle size.
Kohlgraf-Owens, Dana C; Kik, Pieter G
2009-08-17
The linear and nonlinear optical properties of a composite containing interacting spherical silver nanoparticles embedded in a dielectric host are studied as a function of interparticle separation using three dimensional frequency domain simulations. It is shown that for a fixed amount of metal, the effective third-order nonlinear susceptibility of the composite chi((3))(omega) can be significantly enhanced with respect to the linear optical properties, due to a combination of resonant surface plasmon excitation and local field redistribution. It is shown that this geometry-dependent susceptibility enhancement can lead to an improved figure of merit for nonlinear absorption. Enhancement factors for the nonlinear susceptibility of the composite are calculated, and the complex nature of the enhancement factors is discussed.
Mohan, Sabitha; Lange, Jens; Graener, Heinrich; Seifert, Gerhard
2012-12-17
The nonlinear optical properties of nanocomposites consisting of non-spherical silver nanoparticles in glass matrix have been studied using the femtosecond Z-scan technique. The spheroidal nanoparticles were uniformly oriented along a common direction. By polarization sensitive studies, longitudinal and transverse plasmon resonances can be addressed separately. A sign reversal in optical nonlinearity from negative to positive is observed while switching the light interaction from near to non-resonant regime, which can be done by simply rotating the light polarization by 90°. Studying samples with different aspect ratio, we obtained the dispersion of third-order nonlinearity in the near-resonant regime, showing an enhancement of the nonlinear processes by more than two orders of magnitude due to the electric field enhancement at the surface plasmon resonance.
Indian Academy of Sciences (India)
Tarun K Mandal; Sudipta Dutta; Swapan K Pati
2009-09-01
We have investigated the structural aspects of several carbon dioxide molecular aggregates and their spectroscopic and nonlinear optical properties within the quantum chemical theory framework. We find that, although the single carbon dioxide molecule prefers to be in a linear geometry, the puckering of angles occur in oligomers because of the intermolecular interactions. The resulting dipole moments reflect in the electronic excitation spectra of the molecular assemblies. The observation of significant nonlinear optical properties suggests the potential application of the dense carbon dioxide phases in opto-electronic devices.
Nonlinear Optical Absorption of Organic Molecules for Applications in Optical Devices
Boni, Leonardo De; Daniel S. Correa; Mendonca, Cleber R.
2010-01-01
This chapter aimed to describe the resonant nonlinear optical properties of four important organic molecules: Chlorophyll A, Indocyanine Green, Ytterbium Bisphthalocyanine and Cytochrome C, which are materials that present interesting optical nonlinearities for applications in optical devices. It was shown that Chlorophyll A solution exhibits a RSA process for Q-switched and mode-locked laser pulses, with an intersystem-crossing time relatively fast and a triplet state cross section value twi...
Rydberg-induced optical nonlinearities from a cold atomic ensemble trapped inside a cavity
Boddeda, R.; Usmani, I.; Bimbard, E.; Grankin, A.; Ourjoumtsev, A.; Brion, E.; Grangier, P.
2016-04-01
We experimentally characterize the optical nonlinear response of a cold atomic medium placed inside an optical cavity, and excited to Rydberg states. The excitation to S and D Rydberg levels is carried out via a two-photon transition in an electromagnetically induced transparency configuration, with a weak (red) probe beam on the lower transition, and a strong (blue) coupling beam on the upper transition. The observed optical nonlinearities induced by S states for the probe beam can be explained using a semi-classical model with van der Waals’ interactions. For the D states, it appears necessary to take into account a dynamical decay of Rydberg excitations into a long-lived dark state. We show that the measured nonlinearities can be explained by using a Rydberg bubble model with a dynamical decay.
Rydberg-induced optical nonlinearities from a cold atomic ensemble trapped inside a cavity
Boddeda, Rajiv; Bimbard, Erwan; Grankin, Andrey; Ourjoumtsev, Alexei; Brion, Etienne; Grangier, Philippe
2015-01-01
We experimentally characterize the optical nonlinear response of a cold atomic medium placed inside an optical cavity, and excited to Rydberg states. The excitation to S and D Rydberg levels is carried out via a two-photon transition in an EIT (electromagnetically induced transparency) configuration, with a weak (red) probe beam on the lower transition, and a strong (blue) coupling beam on the upper transition. The observed optical nonlinearities induced by S states for the probe beam can be explained using a semi-classical model with van der Waals' interactions. For the D states, it appears necessary to take into account a dynamical decay of Rydberg excitations into a long-lived dark state. We show that the measured nonlinearities can be explained by using a Rydberg bubble model with a dynamical decay.
Dynamic computer-generated nonlinear-optical holograms
Liu, Haigang; Li, Jun; Fang, Xiangling; Zhao, Xiaohui; Zheng, Yuanlin; Chen, Xianfeng
2017-08-01
We propose and experimentally demonstrate dynamic nonlinear optical holograms by introducing the concept of computer-generated holograms for second-harmonic generation of a structured fundamental wave with a specially designed wave front. The generation of Laguerre-Gaussian second-harmonic beams is investigated in our experiment. Such a method, which only dynamically controls the wave front of the fundamental wave by a spatial light modulator, does not need domain inversion in nonlinear crystals and hence is a more flexible way to achieve the off-axis nonlinear second-harmonic beams. It can also be adopted in other schemes and has potential applications in nonlinear frequency conversion, optical signal processing, and real-time hologram, etc.
Dissipation-induced optical nonlinearity at low light levels
Greenberg, Joel A
2011-01-01
We observe a dissipation-induced nonlinear optical process in a gas of cold atoms that gives rise to large nonlinear coupling strengths with high transparency. The nonlinearity results from the simultaneous cooling and crystallization of the gas, and can give rise to efficient Bragg scattering in the form of a six-wave-mixing process at low-light-levels with an extremely large effective fifth-order nonlinear susceptibility of \\chi^(5)= 7.6 x 10-15 (m/V)^4. For large optical gains, collective scattering due to the strong light-matter coupling leads to slow group velocities (~c/105) and long atomic coherence times (~100 {\\mu}s).
Dark Spatial Soliton Interaction in Nonlinear Kerr Medium
Institute of Scientific and Technical Information of China (English)
LuchuanWANG; QinliangFAN
1998-01-01
The dark spatial soliton interaction in nonlinear Kerr medium has been studied in this paper.The problem has been solved by the use of the slowly varying envelope approximation in solving coupled nonlinear Schroedinger equations.The perturbation nature of dark spatial soliton interaction has been described and some of their key properties has been discussed as well in the paper.
Anomalous interaction of nonlocal solitons in media with competing nonlinearities
DEFF Research Database (Denmark)
Esbensen, B. K.; Bache, Morten; Bang, Ole
2012-01-01
We theoretically investigate properties of individual bright spatial solitons and their interaction in nonlocal media with competing focusing and defocusing nonlinearities. We consider the general case with both nonlinear responses characterized by different strengths and degrees of nonlocality. We...... and interaction of solitons using numerical simulations of the full model of beam propagation. The numerical simulations fully confirm our analytical results....
Nonlinear optical properties of sodium copper chlorophyllin in aqueous solution.
Li, Jiangting; Peng, Yufeng; Han, Xueyun; Guo, Shaoshuai; Liang, Kunning; Zhang, Minggao
2017-06-16
Sodium copper chlorophyllin (SCC), as one of the derivatives of chlorophyll - with its inherent green features; good stability for heat, light, acids and alkalies; unique antimicrobial capability; and particular deodori zation performance - is widely applied in some fields such as the food industry, medicine and health care, daily cosmetic industry etc. SCC, as one of the metal porphyrins, has attracted much attention because of its unique electronic band structure and photon conversion performance. To promote the application of SCC in materials science; energy research and photonics, such as fast optical communications; and its use in nonlinear optical materials, solar photovoltaic cells, all-optical switches, optical limiters and saturable absorbers, great efforts should be dedicated to studying its nonlinear optical (NLO) properties. In this study, the absorption spectra and NLO properties of SCC in aqueous solution at different concentrations were measured. The Z-scan technique was used to determine NLO properties. The results indicated that the absorption spectra of SCC exhibit 2 characteristic absorption peaks located at the wavelengths 405 and 630 nm, and the values of the peaks increase with increasing SCC concentration. The results also showed that SCC exhibits reverse saturation absorption and negative nonlinear refraction (self-defocusing). It can be seen that SCC has good optical nonlinearity which will be convenient for applications in materials science, energy research and photonics.
Nonlinear optical and magneto-optical effects in non-spherical magnetic granular composite
Institute of Scientific and Technical Information of China (English)
Ping Xu(须萍); Zhenya Li(李振亚)
2004-01-01
The magnetization-induced nonlinear optical and nonlinear magneto-optical properties in a magnetic metal-insulator composite are studied based on a tensor effective medium approximation with shape factor and Taylcr-expansion method. There is a weakly nonlinear relation between electric displacement D and elcctric field E in the composite. The results of our studies on the effective dielectric tensor and the nonlinear susceptibility tensor in a magnetic nanocomposite are surveyed. It is shown that such a metal-insulator composite exhibits the enhancements of optical and magneto-optical nonlinearity. The frequencies at which the enhancements occur, and the amplitude of the enhancement factors depend on the concentration and shape of the magnetic grains.
Linear and nonlinear optical properties of tellurite glasses
Jin, Zhian
Tellurite glasses have been widely studied from bulk materials to structured devices, with the emphasis on the development of nonlinear optical fibers to demonstrate the functionalities of supercontinuum generation, erbium doped fiber amplifier and Raman amplifiers, etc. The new type tellurite-based optical fibers exhibit superior advantages over conventional silica ones, due to their high optical nonlinearity, broad transmission window, high rare earth element solubility and Raman gain intensity. Like silica fibers, tellurite fibers may also incorporate various fiber structures including solid core-cladding one and microstructure one (e.g. photonic crystal). The fiber loss was ever reported as low as ˜1dB/m using rod-in-tube fabrication process. Beyond all those progresses, little success has been made on improving the optical nonlinear property of tellurite glasses chi(3) ˜ 50 times bigger than fused silica). The challenge remains for tellurite glasses that their optical nonlinearity is more than 1 order smaller to compare with chalcogenides, although they are more stable chemically and structurally. In this work, after carefully reviewing the trend of optical nonlinearity for solid glasses, we adopted two strategies to potentially increase the linear and third-order optical nonlinear properties for tellurite glasses. A more polarizable electronic excitation may be achievable by introducing chalcogen elements (e.g. Sulfur or Selenium) into TeO2 vitreous network and synthesizing glasses with a linear helical chainlike structure. The ab initio computational results of microscopic hyper-polarizabilities of hypothetical mixed - 2 - tellurite chalcogenide glass molecular structure (TeO2(TeOX)n) confirmed the enhanced effect as Te-X (X=S or Se) bonds exist and the molecular size (n) grows. Quantitative estimates of the macroscopic linear and nonlinear properties for a mixed glass made from chains of n = 5 units leads to a conclusion that the extra Te-S (or Te
Photoconductive and nonlinear optical properties of composites based on metallophthalocyanines
Vannikov, A. V.; Grishina, A. D.; Gorbunova, Yu. G.; Tsivadze, A. Yu.
2015-08-01
The photoconductive, photorefractive and nonlinear optical properties of composites from polyvinylcarbazole or aromatic polyimide containing supramolecular ensembles of (tetra-15-crown-5) - phthalocyaninato gallium, indium, - phthalocyaninateacetato yttrium, - phthalocyaninato ruthenium with axially coordinated pyrazine molecules were investigated at 633, 1030 and 1064nmusing continuous and pulsed lasers. Supramolecular ensembles (SE) were prepared through dissolution of molecular metallophthalocyanines in tetrachloroethane (TCE) and subsequent treatment via three cycles of heating to 90∘C and slow cooling to room temperature. The zscan method in femtosecond and nanosecond regimeswas used for measuring nonlinear optical properties phthalocyaninato indium and yttrium in TCE solutions and polymer films. It was established that effect of heavy metallic atom is basic factor which determines the quantum yield, photorefractive amplification of laser object beam, dielectric susceptibility of third order and nonlinear optical properties of metallophthalocyanines.
Nonlinear optical studies of single gold nanoparticles
Dijk, Meindert Alexander van
2007-01-01
Gold nanoparticles are spherical clusters of gold atoms, with diameters typically between 1 and 100 nanometers. The applications of these particles are rather diverse, from optical labels for biological experiments to data carrier for optical data storage. The goal of my project was to develop new
Conservation Laws in Higher-Order Nonlinear Optical Effects
Kim, J; Shin, H J; Kim, Jongbae
1999-01-01
Conservation laws of the nonlinear Schrödinger equation are studied in the presence of higher-order nonlinear optical effects including the third-order dispersion and the self-steepening. In a context of group theory, we derive a general expression for infinitely many conserved currents and charges of the coupled higher-order nonlinear Schrödinger equation. The first few currents and charges are also presented explicitly. Due to the higher-order effects, conservation laws of the nonlinear Schrödinger equation are violated in general. The differences between the types of the conserved currents for the Hirota and the Sasa-Satsuma equations imply that the higher-order terms determine the inherent types of conserved quantities for each integrable cases of the higher-order nonlinear Schrödinger equation.
Theory of plasmonic effects in nonlinear optics: the case of graphene
Rostami, Habib; Polini, Marco
2016-01-01
We develop a microscopic large-$N$ theory of electron-electron interaction corrections to multi-legged Feynman diagrams describing second- and third-order nonlinear response functions. Our theory, which reduces to the well-known random phase approximation in the linear-response limit, is completely general and is useful to understand all second- and third-order nonlinear effects, including harmonic generation, wave mixing, and photon drag. We apply our theoretical framework to the case of graphene, by carrying out microscopic calculations of the second- and third-order nonlinear response functions of an interacting two-dimensional (2D) gas of massless Dirac fermions. We compare our results with recent measurements, where all-optical launching of graphene plasmons has been achieved by virtue of the finiteness of the quasi-homogeneous second-order nonlinear response of this inversion-symmetric 2D material.
From Ewald sphere to Ewald shell in nonlinear optics
Huang, Huang; Huang, Cheng-Ping; Zhang, Chao; Hong, Xu-Hao; Zhang, Xue-Jin; Qin, Yi-Qiang; Zhu, Yong-Yuan
2016-07-01
Ewald sphere is a simple vector scheme to depict the X-ray Bragg diffraction in a crystal. A similar method, known as the nonlinear Ewald sphere, was employed to illustrate optical frequency conversion processes. We extend the nonlinear Ewald sphere to the Ewald shell construction. With the Ewald shell, a variety of quasi-phase-matching (QPM) effects, such as the collective envelope effect associated with multiple QPM resonances, the enhanced second- harmonic generation due to multiple reciprocal vectors etc., are suggested theoretically and verified experimentally. By rotating the nonlinear photonic crystal sample, the dynamic evolution of these QPM effects has also been observed, which agreed well with the Ewald shell model.
Pulse operation of semiconductor laser with nonlinear optical feedback
Guignard, Celine; Besnard, Pascal; Mihaescu, Adrian; MacDonald, K. F.; Pochon, Sebastien; Zheludev, Nikolay I.
2004-09-01
A semiconductor laser coupled to a gallium-made non linear mirror may exhibit pulse regime. In order to better understand this coupled cavity, stationary solutions and dynamics are described following the standard Lang and Kobayashi equations for a semiconductor laser submitted to nonlinear optical feedback. It is shown that the nonlinearity distorts the ellipse on which lied the stationary solutions, with a ``higher'' part corresponding to lower reflectivity and a ``lower'' part to higher reflectivity. Bifurcation diagrams and nonlinear analysis are presented while the conditions for pulsed operation are discussed.
Dispersion of the nonlinear refractive index of optical crystals
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.
Nonlinear phase noise in coherent optical OFDM transmission systems.
Zhu, Xianming; Kumar, Shiva
2010-03-29
We derive an analytical formula to estimate the variance of nonlinear phase noise caused by the interaction of amplified spontaneous emission (ASE) noise with fiber nonlinearity such as self-phase modulation (SPM), cross-phase modulation (XPM), and four-wave mixing (FWM) in coherent orthogonal frequency division multiplexing (OFDM) systems. The analytical results agree very well with numerical simulations, enabling the study of the nonlinear penalties in long-haul coherent OFDM systems without extensive numerical simulation. Our results show that the nonlinear phase noise induced by FWM is significantly larger than that induced by SPM and XPM, which is in contrast to traditional WDM systems where ASE-FWM interaction is negligible in quasi-linear systems. We also found that fiber chromatic dispersion can reduce the nonlinear phase noise. The variance of the total phase noise increases linearly with the bit rate, and does not depend significantly on the number of subcarriers for systems with moderate fiber chromatic dispersion.
Dynamics of optical rogue waves in inhomogeneous nonlinear waveguides
Institute of Scientific and Technical Information of China (English)
Zhang Jie-Fang; Jin Mei-Zhen; He Ji-Da; Lou Ji-Hui; Dai Chao-Qing
2013-01-01
We propose a unified theory to construct exact rogue wave solutions of the (2+1)-dimensional nonlinear Schr(o)dinger equation with varying coefficients.And then the dynamics of the first-and the second-order optical rogues are investigated.Finally,the controllability of the optical rogue propagating in inhomogeneous nonlinear waveguides is discussed.By properly choosing the distributed coefficients,we demonstrate analytically that rogue waves can be restrained or even be annihilated,or emerge periodically and sustain forever.We also figure out the center-of-mass motion of the rogue waves.
Modeling of Nonlinear Signal Distortion in Fiber-Optical Networks
Johannisson, Pontus
2013-01-01
A low-complexity model for signal quality prediction in a nonlinear fiber-optical network is developed. The model, which builds on the Gaussian noise model, takes into account the signal degradation caused by a combination of chromatic dispersion, nonlinear signal distortion, and amplifier noise. The center frequencies, bandwidths, and transmit powers can be chosen independently for each channel, which makes the model suitable for analysis and optimization of resource allocation, routing, and scheduling in large-scale optical networks applying flexible-grid wavelength-division multiplexing.
Hybrid quantum systems for enhanced nonlinear optical susceptibilities
Sullivan, Dennis; Kuzyk, Mark G
2016-01-01
Significant effort has been expended in the search for materials with ultra-fast nonlinear-optical susceptibilities, but most fall far below the fundamental limits. This work applies a theoretical materials development program that has identified a promising new hybrid made of a nanorod and a molecule. This system uses the electrostatic dipole moment of the molecule to break the symmetry of the metallic nanostructure that shifts the energy spectrum to make it optimal for a nonlinear-optical response near the fundamental limit. The structural parameters are varied to determine the ideal configuration, providing guidelines for making the best structures.
Weakly Nonlinear Geometric Optics for Hyperbolic Systems of Conservation Laws
Chen, Gui-Qiang; Zhang, Yongqian
2012-01-01
We establish an $L^1$-estimate to validate the weakly nonlinear geometric optics for entropy solutions of nonlinear hyperbolic systems of conservation laws with arbitrary initial data of small bounded variation. This implies that the simpler geometric optics expansion function can be employed to study the properties of general entropy solutions to hyperbolic systems of conservation laws. Our analysis involves new techniques which rely on the structure of the approximate equations, besides the properties of the wave-front tracking algorithm and the standard semigroup estimates.
Third-Order Optical Nonlinearity in Novel Porphyrin Dimers
Institute of Scientific and Technical Information of China (English)
PEI Song-Hao; ZHAO Da-Peng; ZHANG Wei; ZHENG Wen-Qi; WANG Xing-Qiao; PENG Wei-Xian; SHI Guang; SONG Ying-Lin
2008-01-01
@@ We investigate the third-order optical nonlinearities in four novel porphyrin dimers (directs A to I)) and a monomeric porphyrin H2 CPTPP measured by using the single-beam z-scan technique with a pulsed Q-switched Nd:YAG nanosecond laser at 532nm.All the samples show strong excited state absorption (ESA) and high value of X(3) in the ns domain at this wavelength.We perform a comparison between dimer A and its monomer H2 CPTPP in their third-order optical nonlinearity, and discuss the relationships between the values of X(3) and the different bridging groups for all the dimers.
High-speed signal processing using highly nonlinear optical fibres
DEFF Research Database (Denmark)
Peucheret, Christophe; Oxenløwe, Leif Katsuo; Mulvad, Hans Christian Hansen
2009-01-01
relying on the phase of the optical field. Topics covered include all-optical switching of 640 Gbit/s and 1.28 Tbit/s serial data, wavelength conversion at 640 Gbit/s, optical amplitude regeneration of differential phase shift keying (DPSK) signals, as well as midspan spectral inversion for differential 8......We review recent progress in all-optical signal processing techniques making use of conventional silica-based highly nonlinear fibres. In particular, we focus on recent demonstrations of ultra-fast processing at 640 Gbit/s and above, as well as on signal processing of novel modulation formats...
40-Gb/s all-optical wavelength conversion based on a nonlinear optical loop mirror
DEFF Research Database (Denmark)
Yu, Jianjun; Zheng, Xueyan; Peucheret, Christophe
2000-01-01
All-optical wavelength conversion based on a nonlinear optical loop mirror (NOLM) at 40 Gb/s is demonstrated for the first time. The effect of walkoff time between control beam and signal beams is investigated when the NOLM is used as an all-optical wavelength converter or an all...
Recent Advances in Graphene-Assisted Nonlinear Optical Signal Processing
Directory of Open Access Journals (Sweden)
Jian Wang
2016-01-01
Full Text Available Possessing a variety of remarkable optical, electronic, and mechanical properties, graphene has emerged as an attractive material for a myriad of optoelectronic applications. The wonderful optical properties of graphene afford multiple functions of graphene based polarizers, modulators, transistors, and photodetectors. So far, the main focus has been on graphene based photonics and optoelectronics devices. Due to the linear band structure allowing interband optical transitions at all photon energies, graphene has remarkably large third-order optical susceptibility χ(3, which is only weakly dependent on the wavelength in the near-infrared frequency range. The graphene-assisted four-wave mixing (FWM based wavelength conversions have been experimentally demonstrated. So, we believe that the potential applications of graphene also lie in nonlinear optical signal processing, where the combination of its unique large χ(3 nonlinearities and dispersionless over the wavelength can be fully exploited. In this review article, we give a brief overview of our recent progress in graphene-assisted nonlinear optical device and their applications, including degenerate FWM based wavelength conversion of quadrature phase-shift keying (QPSK signal, phase conjugated wavelength conversion by degenerate FWM and transparent wavelength conversion by nondegenerate FWM, two-input and three-input high-base optical computing, and high-speed gate-tunable terahertz coherent perfect absorption (CPA using a split-ring graphene.
Liu, Jing; Xia, Jiarui; Song, Peng; Ding, Yong; Cui, Yanling; Liu, Xuemei; Dai, Yumei; Ma, Fengcai
2014-08-25
The ground- and excited-state properties of benzene-linked bisphenalenyl (B-LBP), naphthaline-linked bisphenalenyl (N-LBP), and anthracene-linked bisphenalenyl (A-LBP) Kekulé molecules and their respective one-dimensional (1D) stacks are investigated using time-dependent density functional theory (TD-DFT) and a range of extensive multidimensional visualization techniques. The results reveal a covalent π-π bonding interaction between overlapping phenalenyl radicals whose bond length is shorter than the van der Waals distance between carbon atoms. Increasing the linker length and/or number of molecules involved in the 1D stack decreases the HOMO-LUMO energy gap and increases the wavelength of the systems. The charge-transfer mechanism and electron coherence both differ with changes in the linker length and/or number of molecules involved in the 1D stack. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Optics in a nonlinear gravitational wave
Harte, Abraham I
2015-01-01
Gravitational waves can act like gravitational lenses, affecting the observed positions, brightnesses, and redshifts of distant objects. Exact expressions for such effects are derived here, allowing for arbitrarily-moving sources and observers in the presence of plane-symmetric gravitational waves. The commonly-used predictions of linear perturbation theory are shown to be generically overshadowed---even for very weak gravitational waves---by nonlinear effects when considering observations of sufficiently distant sources; higher-order perturbative corrections involve secularly-growing terms which cannot necessarily be neglected. Even on more moderate scales where linear effects remain at least marginally dominant, nonlinear corrections are qualitatively different from their linear counterparts. There is a sense in which they can, for example, mimic the existence of a third type of gravitational wave polarization.
Optics in a nonlinear gravitational plane wave
Harte, Abraham I.
2015-09-01
Gravitational waves can act like gravitational lenses, affecting the observed positions, brightnesses, and redshifts of distant objects. Exact expressions for such effects are derived here in general relativity, allowing for arbitrarily-moving sources and observers in the presence of plane-symmetric gravitational waves. At least for freely falling sources and observers, it is shown that the commonly-used predictions of linear perturbation theory can be generically overshadowed by nonlinear effects; even for very weak gravitational waves, higher-order perturbative corrections involve secularly-growing terms which cannot necessarily be neglected when considering observations of sufficiently distant sources. Even on more moderate scales where linear effects remain at least marginally dominant, nonlinear corrections are qualitatively different from their linear counterparts. There is a sense in which they can, for example, mimic the existence of a third type of gravitational wave polarization.
Nonlinear optical properties and optical power limiting effect of Giemsa dye
Al-Saidi, Imad Al-Deen Hussein A.; Abdulkareem, Saif Al-Deen
2016-08-01
The nonlinear optical properties of Giemsa dye in chloroform solution for different concentrations and dye mixed with poly(methylmethacrylate) (PMMA) as a dye-doped polymer film were investigated using continuous wave (CW) low power solid-state laser (SSL) operating at wavelength of 532 nm as an excitation source. Using the single beam z-scan technique, the nonlinear refractive index (n2), the nonlinear absorption coefficient (β), and the third-order nonlinear optical susceptibility (χ(3)) of Giemsa dye were measured. The measurements reveal that both n2 and β are dependent on the dye concentration. The obtained results indicate that the Giemsa dye exhibits positive nonlinear saturable absorption (SA) and negative refraction nonlinearity, manifestation of self-defocusing effect. Optical power limiting characteristics of the Giemsa dye at different concentrations in solution and polymer film were studied. The observed large third-order optical nonlinearity of Giemsa dye confirms that Giemsa dye is a promising nonlinear material for the optical power limiting and photonic devices applications.
Materials for Nonlinear Optics Chemical Perspectives
1991-01-01
introduced into LB muldilayers built from 1/1 mixtures with an amphiphilic cyclodextrin . The polyenic chains are again perpendicular to the substrate...molecules in inorganic matrices. The encapsulated molecules can be used to induce new optical properties in the material or to probe the changes at the...glass are discussed here. First, laser dyes including rhodamines and coumarins are encapsulated . The resulting doped gel-glasses exhibit optical gain
Nonlinear Real-Time Optical Signal Processing.
1983-12-01
8217 " University of Southern CaliforniaN JU Los Angeles, California 90089-0272 " --;984. ,’ I ’I Research Sponsored by the ., k Air Force Office of...concentrates on experimental results from the sixteen gate clocked master-slave optical flip-flop. A second paper " Architectures for a Sequential Optical Logic...purpose computer could permit the realization of a number of architectural advantages over semiconductor electronics [27]. These advantages include
Optical Beams in Nonlocal Nonlinear Media
DEFF Research Database (Denmark)
Królikowski, W.; Bang, Ole; Wyller, J.
2003-01-01
We discuss propagation of optical beams in nonlocal Kerr-like media with the nonlocality of general form. We study the effect of nonlocality on modulational instability of the plane wave fronts, collapse of finite beams and formation of spatial solitons.......We discuss propagation of optical beams in nonlocal Kerr-like media with the nonlocality of general form. We study the effect of nonlocality on modulational instability of the plane wave fronts, collapse of finite beams and formation of spatial solitons....
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.
Chip scale low dimensional materials: optoelectronics & nonlinear optics
Gu, Tingyi
The CMOS foundry infrastructure enables integration of high density, high performance optical transceivers. We developed integrated devices that assemble resonators, waveguide, tapered couplers, pn junction and electrodes. Not only the volume standard manufacture in silicon foundry is promising to low-lost optical components operating at IR and mid-IR range, it also provides a robust platform for revealing new physical phenomenon. The thesis starts from comparison between photonic crystal and micro-ring resonators based on chip routers, showing photonic crystal switches have small footprint, consume low operation power, but its higher linear loss may require extra energy for signal amplification. Different designs are employed in their implementation in optical signal routing on chip. The second part of chapter 2 reviews the graphene based optoelectronic devices, such as modulators, lasers, switches and detectors, potential for group IV optoelectronic integrated circuits (OEIC). In chapter 3, the highly efficient thermal optic control could act as on-chip switches and (transmittance) tunable filters. Local temperature tuning compensates the wavelength differences between two resonances, and separate electrode is used for fine tuning of optical pathways between two resonators. In frequency domain, the two cavity system also serves as an optical analogue of Autler-Towns splitting, where the cavity-cavity resonance detuning is controlled by the length of pathway (phase) between them. The high thermal sensitivity of cavity resonance also effectively reflects the heat distribution around the nanoheaters, and thus derives the thermal conductivity in the planar porous suspended silicon membrane. Chapter 4 & 5 analyze graphene-silicon photonic crystal cavities with high Q and small mode volume. With negligible nonlinear response to the milliwatt laser excitation, the monolithic silicon PhC turns into highly nonlinear after transferring the single layer graphene with
Knoester, Jasper; Mukamel, Shaul
1989-01-01
Reduced equations of motion for material and radiation field variables in a molecular crystal are presented that allow us to calculate linear- and nonlinear-optical susceptibilities, accounting in a systematic way for intermolecular interactions. These equations are derived starting from the multipo
Interaction-induced effects in the nonlinear coherent response of quantum-well excitons
DEFF Research Database (Denmark)
Wagner, Hans Peter; Schätz, A.; Langbein, Wolfgang Werner;
1999-01-01
Interaction-induced processes are studied using the third-order nonlinear polarization created in polarization-dependent four-wave-mixing experiments (FWM) on a ZnSe single quantum well. We discuss their influence by a comparison of the experimental FWM with calculations based on extended optical...
Management of the orbital angular momentum of vortex beams in a quadratic nonlinear interaction
Bovino, Fabio A; Bertolotti, Mario; Sibilia, Concita
2011-01-01
Light intensity control of the orbital angular momentum of the fundamental beam in a quadratic nonlinear process is theoretically and numerically presented. In particular we analyzed a seeded second harmonic generation process in presence of orbital angular momentum of the interacting beams due both to on axis and off axis optical vortices. Examples are proposed and discussed.
A Strategy for the Development of Macromolecular Nonlinear Optical Materials
1990-01-01
obsolete. SECURITY CLASSIFICATION OF THIS PAGE STRATEGY FOR THE DEVELOPMENT OF MACROMOLECULAR NONLINEAR OPTICAL MATERIALS Braja K. Mandala , Jan-Chan...materials is significantly different from the conventional inorganic NLO materials. The extent of second order (quadratic) NLO effect such as second...is a criterion of paramount importance for a large second order electro-optic effect in organic materials 8 ,9 . The most common approach to obtain
Nonlinear Optical Properties and Femtosecond Laser Micromachining of Special Glasses
Almeida,Juliana M. P.; Gustavo F. B. Almeida; Boni, Leonardo De; Cleber R. Mendonça
2015-01-01
Materials specially designed for photonics have been at the vanguard of chemistry, physics and materials science, driven by the development of new technologies. One particular class of materials investigated in this context are glasses, that in principle should exhibit high third order optical nonlinearities and fast response time, whose optical properties can be tailored by compositional changes, such as, for instance, the incorporation of metallic nanoparticles to explore plasmon resonances...
Harmonic nanoparticles: noncentrosymmetric metal oxides for nonlinear optics
Rogov, Andrii; Mugnier, Yannick; Bonacina, Luigi
2015-01-01
The combination of nonlinear optics and nanotechnology is an extremely rich scientific domain yet widely unexplored. We present here a review of recent optical investigations on noncentrosymmetric oxide nanoparticles with a large ${{\\chi }^{(2)}}$ response, often referred to as harmonic nanoparticles (HNPs). HNPs feature a series of properties which distinguish them from other photonics nanoprobes (quantum dots, up-conversion nanoparticles, noble metal particles). HNPs emission is inherently ...
Guesmi, Latifa; Menif, Mourad
2016-04-01
The field of fiber optics nonlinearity is more discussed last years due to such remarkable enhancement in the nonlinear processes efficiency. In this paper, and for optical performance monitoring (OPM), a new achievement of nonlinear effects has been investigated. The use of cross-phase modulation (XPM) and four-wave mixing (FWM) effects between input optical signal and inserted continuous-wave probe has proposed for impairments monitoring. Indeed, transmitting a multi-channels phase modulated signal at high data rate (1 Tbps WDM Nyquist NRZ- DP-QPSK) improves the sensitivity and the dynamic range monitoring. It was observed by simulation results that various optical parameters including optical power, wavelength, chromatic dispersion (CD), polarization mode dispersion (PMD), optical signal-to-noise ratio (OSNR), Q-factor and so on, can be monitored. Also, the effect of increasing the channel spacing between WDM signals is studied and proved its use for FWM power monitoring.
Structure property relationships for the nonlinear optical response of fullerenes
Rustagi, Kailash C.; Ramaniah, Lavanya M.; Nair, Selvakumar V.
1994-11-01
We present a phenomenological theory of nonlinear optical response of fullerenes. An empirical tight-binding model is used in conjunction with a classical electromagnetic picture for the screening. Since in bulk media such a picture of screening corresponds to the self- consistent field approach, the only additional approximation involved in our approach is the neglect of nonlocality. We obtain reliable estimates for the linear and nonlinear susceptibilities of C60, C70, C76 and other pure carbon fullerenes and also substituted fullerenes. The relatively large values of (beta) that we obtain for C76 and substituted fullerenes appear promising for the development of fullerene-based nonlinear optical materials. Our phenomenological picture of screening provides a good understanding of the linear absorption spectra of higher fullerenes and predicts that a comparison of the one-photon and multi-photon spectra will provide an insight into screening effects in these systems.
Demonstration of a Chip-based Nonlinear Optical Isolator
Hua, Shiyue; Jiang, Xiaoshun; Hua, Qian; Jiang, Liang; Xiao, Min
2016-01-01
Despite fundamentally challenging in integrated (nano)photonics, achieving chip-based light nonreciprocity becomes increasingly urgent in signal processing and optical communications. Because of material incompatibilities in conventional approaches based on Faraday effects, alternative solutions have resorted to nonlinear processes to obtain one-way transmission. However, revealed dynamic reciprocity in a recent theoretical analysis has pinned down the functionalities of these nonlinear isolators. To overcome this dynamic reciprocity, we here report the first demonstration of a nonlinear optical isolator on a silicon chip enforced by phase-matched parametric amplification. Using a high-Q microtoroid resonator, we realize highly nonreciprocal transport at the 1,550 nm wavelength when waves are simultaneously launched in both forward and backward directions. Our design, compatible with current CMOS technique, yields convincing isolation performance with sufficiently low insertion loss for a wide range of input ...
Optoelectronic and nonlinear optical processes in low dimensional semiconductors
Indian Academy of Sciences (India)
B P Singh
2006-11-01
Spatial confinement of quantum excitations on their characteristic wavelength scale in low dimensional materials offers unique possibilities to engineer the electronic structure and thereby control their physical properties by way of simple manipulation of geometrical parameters. This has led to an overwhelming interest in quasi-zero dimensional semiconductors or quantum dots as tunable materials for multitude of exciting applications in optoelectronic and nonlinear optical devices and quantum information processing. Large nonlinear optical response and high luminescence quantum yield expected in these systems is a consequence of huge enhancement of transition probabilities ensuing from quantum confinement. High quantum efficiency of photoluminescence, however, is not usually realized in the case of bare semiconductor nanoparticles owing to the presence of surface states. In this talk, I will focus on the role of quantum confinement and surface states in ascertaining nonlinear optical and optoelectronic properties of II–VI semiconductor quantum dots and their nanocomposites. I will also discuss the influence of nonlinear optical processes on their optoelectronic characteristics.
Generalized dispersive wave emission in nonlinear fiber optics.
Webb, K E; Xu, Y Q; Erkintalo, M; Murdoch, S G
2013-01-15
We show that the emission of dispersive waves in nonlinear fiber optics is not limited to soliton-like pulses propagating in the anomalous dispersion regime. We demonstrate, both numerically and experimentally, that pulses propagating in the normal dispersion regime can excite resonant dispersive radiation across the zero-dispersion wavelength into the anomalous regime.
Investigation of Nonlinear Optical Properties of Semiconductors.
1984-02-23
optical studies of InSb NI. W. Goodwin" and D. G. Seiler Center jo .4pphed Quurntm Electronics, Department of Phytics , North 1exu.% State Unuvpieroty...lnSb, in zero magnetic field, is that of Pidgeon anJ data, aside from two-photon absorption, could be ab- co-workers,’ who give references to other
All-optical signal processing in quadratic nonlinear materials
DEFF Research Database (Denmark)
Johansen, Steffen Kjær
2002-01-01
of materials with a second order nonlinearity, the so-called X(2) materials, is faster and stronger than that of more conventional materials with a cubic nonlinearity. The X(2) materials support spatial solitons consisting of two coupled components, the fundamental wave (FW) and its second harmonic (SH......). During this project the interaction between such spatial solitons has been investigated theoretically through perturbation theory and experimentally via numerical simulations. The outcome of this research isnew theoretical tools for quantitatively predicting the escape angle, i.e. the angle of incidence...... and exploitation of these cubic nonlinearities in two-period QPM wave-guides has been another area of investigation. Introducing the second period might make practical engineering of the nonlinearities possible. A major result is the discovery that cubic nonlinearities leads to an enhancement of the bandwidth...
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.
Decay of high order optical vortices in anisotropic nonlinear optical media
DEFF Research Database (Denmark)
Mamaev, A.V.; Saffman, M.; Zozulya, A.A.
1997-01-01
We present an experimental and theoretical study of the decay of high order optical vortices in media with an anisotropic nonlocal nonlinearity. Vortices with charge n decay into an aligned array of n vortices of unit charge.......We present an experimental and theoretical study of the decay of high order optical vortices in media with an anisotropic nonlocal nonlinearity. Vortices with charge n decay into an aligned array of n vortices of unit charge....
Implementation of Nonlinear Control Laws for an Optical Delay Line
Hench, John J.; Lurie, Boris; Grogan, Robert; Johnson, Richard
2000-01-01
This paper discusses the implementation of a globally stable nonlinear controller algorithm for the Real-Time Interferometer Control System Testbed (RICST) brassboard optical delay line (ODL) developed for the Interferometry Technology Program at the Jet Propulsion Laboratory. The control methodology essentially employs loop shaping to implement linear control laws. while utilizing nonlinear elements as means of ameliorating the effects of actuator saturation in its coarse, main, and vernier stages. The linear controllers were implemented as high-order digital filters and were designed using Bode integral techniques to determine the loop shape. The nonlinear techniques encompass the areas of exact linearization, anti-windup control, nonlinear rate limiting and modal control. Details of the design procedure are given as well as data from the actual mechanism.
Few-photon coherent nonlinear optics with a single molecule
Maser, Andreas; Utikal, Tobias; Götzinger, Stephan; Sandoghdar, Vahid
2015-01-01
The pioneering experiments of linear spectroscopy were performed using flames in the 1800s, but nonlinear optical measurements had to wait until lasers became available in the twentieth century. Because the nonlinear cross section of materials is very small, usually macroscopic bulk samples and pulsed lasers are used. Numerous efforts have explored coherent nonlinear signal generation from individual nanoparticles or small atomic ensembles with millions of atoms. Experiments on a single semiconductor quantum dot have also been reported, albeit with a very small yield. Here, we report on coherent nonlinear spectroscopy of a single molecule under continuous-wave single-pass illumination, where efficient photon-molecule coupling in a tight focus allows switching of a laser beam by less than a handful of pump photons nearly resonant with the sharp molecular transition. Aside from their fundamental importance, our results emphasize the potential of organic molecules for applications such as quantum information pro...
Broadband excitation and collection in fiber-optic nonlinear endomicroscopy
Prakash Ghimire, Navin; Bao, Hongchun; Gu, Min
2013-08-01
Broadband excitation and collection in a fiber-optic nonlinear endomicroscope are realized by using a single hollow-core double-clad photonic crystal fiber and a gradient index lens. Femtosecond pulses with central wavelengths in the range of 750-850 nm can be directly delivered through the core of the fiber for nonlinear excitation without pre-chirping. A gradient index lens with numerical aperture 0.8 designed to operate over the near-infrared wavelength range is used for focusing the laser beam from the fiber for nonlinear excitation and for collecting the fluorescent signal from the sample. This compact system is suitable to perform nonlinear imaging of multiple fluorophors in the wavelength range of 750-850 nm.
Nonlinear interactions of electromagnetic waves with the auroral ionosphere
Wong, Alfred Y.
1999-09-01
The ionosphere provides us with an opportunity to perform plasma experiments in an environment with long confinement times, very large-scale lengths, and no confining walls. The auroral ionosphere with its nearly vertical magnetic field geometry is uniquely endowed with large amount of free energy from electron and ion precipitation along the magnetic field and mega-ampere current across the magnetic field. To take advantage of this giant outdoor laboratory, two facilities HAARP and HIPAS, with frequencies ranging from the radio to optical bands, are now available for active probing of and interaction with this interesting region. The ponderomotive pressures from the self-consistent wave fields have produced significant local perturbations of density and particle distributions at heights where the incident EM frequency matches a plasma resonance. This paper will review theory and experiments covering the nonlinear phenomena of parametric decay instability to wave collapse processes. At HF frequencies plasma lenses can be created by preconditioning pulses to focus what is a normally divergent beam into a high-intensity spot to further enhance nonlinear phenomena. At optical wavelengths a large rotating liquid metal mirror is used to focus laser pulses up to a given height. Such laser pulses are tuned to the same wavelengths of selected atomic and molecular resonances, with resulting large scattering cross sections. Ongoing experiments on dual-site experiments and excitation of ELF waves will be presented. The connection of such basic studies to environmental applications will be discussed. Such applications include the global communication using ELF waves, the ozone depletion and remediation and the control of atmospheric CO2 through the use of ion cyclotron resonant heating.
DEFF Research Database (Denmark)
Guo, Hairun; Zeng, Xianglong; Zhou, Binbin
2013-01-01
We interpret the purely spectral forward Maxwell equation with up to third-order induced polarizations for pulse propagation and interactions in quadratic nonlinear crystals. The interpreted equation, also named the nonlinear wave equation in the frequency domain, includes quadratic and cubic...
2015-09-17
processing - optical frequency conversion and optical DSB -to-SSB conversion 5a. CONTRACT NUMBER FA2386-14-1-0006 5b. GRANT NUMBER Grant 134113...nonlinear dynamics of semiconductor lasers for certain optical signal processing functionalities, including optical DSB -to-SSB conversion, photonic...conversion and optical DSB -to-SSB conversion Performance Period May 30, 2014 ~ May 29, 2015 Principal Investigator Name: Sheng-Kwang Hwang Position
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.
Power-transfer effects in monomode optical nonlinear waveguiding structures.
Jakubczyk, Z; Jerominek, H; Patela, S; Tremblay, R; Delisle, C
1987-09-01
We describe power-transfer effects, over a certain threshold, among constituents of planar waveguiding structures consisting of an optical linear layer deposited onto a nonlinear substrate (CdS(x)Se(1-x)-doped glass). Proper selection of the thickness of the linear waveguiding film and the refractive index of the linear cladding allows one to obtain optical transistor action and to construct all-optical AND, OR, NOT, and XOR logic gates. The effects appear for the TE(0) guided mode.
Covariant Description of Transformation Optics in Linear and Nonlinear Media
Paul, Oliver
2011-01-01
The technique of transformation optics (TO) is an elegant method for the design of electromagnetic media with tailored optical properties. In this paper, we focus on the formal structure of TO theory. By using a complete covariant formalism, we present a general transformation law that holds for arbitrary materials including bianisotropic, magneto-optical, nonlinear and moving media. Due to the principle of general covariance, the formalism is applicable to arbitrary space-time coordinate transformations and automatically accounts for magneto-electric coupling terms. The formalism is demonstrated for the calculation of the second harmonic generation in a twisted TO concentrator.
Vukovic, N.; Healy, N.; Suhailin, F. H.; Mehta, P.; Day, T. D.; Badding, J. V.; Peacock, A. C.
2013-10-01
Microresonators are ideal systems for probing nonlinear phenomena at low thresholds due to their small mode volumes and high quality (Q) factors. As such, they have found use both for fundamental studies of light-matter interactions as well as for applications in areas ranging from telecommunications to medicine. In particular, semiconductor-based resonators with large Kerr nonlinearities have great potential for high speed, low power all-optical processing. Here we present experiments to characterize the size of the Kerr induced resonance wavelength shifting in a hydrogenated amorphous silicon resonator and demonstrate its potential for ultrafast all-optical modulation and switching. Large wavelength shifts are observed for low pump powers due to the high nonlinearity of the amorphous silicon material and the strong mode confinement in the microcylindrical resonator. The threshold energy for switching is less than a picojoule, representing a significant step towards advantageous low power silicon-based photonic technologies.
Detecting nonlinear acoustic waves in liquids with nonlinear dipole optical antennae
Maksymov, Ivan S
2015-01-01
Ultrasound is an important imaging modality for biological systems. High-frequency ultrasound can also (e.g., via acoustical nonlinearities) be used to provide deeply penetrating and high-resolution imaging of vascular structure via catheterisation. The latter is an important diagnostic in vascular health. Typically, ultrasound requires sources and transducers that are greater than, or of order the same size as the wavelength of the acoustic wave. Here we design and theoretically demonstrate that single silver nanorods, acting as optical nonlinear dipole antennae, can be used to detect ultrasound via Brillouin light scattering from linear and nonlinear acoustic waves propagating in bulk water. The nanorods are tuned to operate on high-order plasmon modes in contrast to the usual approach of using fundamental plasmon resonances. The high-order operation also gives rise to enhanced optical third-harmonic generation, which provides an important method for exciting the higher-order Fabry-Perot modes of the dipole...
Three-Wave Resonant Interactions in Self-Defocusing Optical Media
Institute of Scientific and Technical Information of China (English)
崔维娜; 黄国翔; 孙春柳
2003-01-01
A three-wave resonant interaction for nonlinear excitations created from a continuous-wave background is shown to be possible in an isotropic optical medium with a self-defocusing cubic nonlinearity. Under suitable phasematching conditions the nonlinear envelope equations for the resonant interaction are derived by using a method of multiple-scales. Some explicit three-wave solitary wave and lump solutions are discussed.
VARIANCE OF NONLINEAR PHASE NOISE IN FIBER-OPTIC SYSTEM
RANJU KANWAR; SAMEKSHA BHASKAR
2013-01-01
In communication system, the noise process must be known, in order to compute the system performance. The nonlinear effects act as strong perturbation in long- haul system. This perturbation effects the signal, when interact with amplitude noise, and results in random motion of the phase of the signal. Based on the perturbation theory, the variance of nonlinear phase noise contaminated by both self- and cross-phase modulation, is derived analytically for phase-shift- keying system. Through th...
Third-order optical nonlinearities of PVP/Pd nanohybrids
Papagiannouli, I.; Potamianos, D.; Krasia-Christoforou, T.; Couris, S.
2017-10-01
Pd nanoparticles stabilized by polyvinylpyrrolidone were synthesized following mild reduction of palladium ion complexes. Their morphology and optical properties were characterized using Transmission Electron Microscopy, Dynamic Light Scattering and UV-Vis absorption spectroscopy to confirm the existence of monodispersed, low-dimensional single nanoparticles. Furthermore, their third-order nonlinear optical properties were investigated by means of the Z-scan technique, using 35 ps and 4 ns laser pulses, both in the visible (532 nm) and in the infrared (1064 nm). These results denote that the surface plasmon resonance is not significantly contributing to the nonlinear optical response of Pd nanoparticles. In contrast, a two photon absorption process was found to contribute to the observed response. The present results are discussed and compared with previous literature findings.
Nonlinear Silicon Photonic Signal Processing Devices for Future Optical Networks
Directory of Open Access Journals (Sweden)
Cosimo Lacava
2017-01-01
Full Text Available In this paper, we present a review on silicon-based nonlinear devices for all optical nonlinear processing of complex telecommunication signals. We discuss some recent developments achieved by our research group, through extensive collaborations with academic partners across Europe, on optical signal processing using silicon-germanium and amorphous silicon based waveguides as well as novel materials such as silicon rich silicon nitride and tantalum pentoxide. We review the performance of four wave mixing wavelength conversion applied on complex signals such as Differential Phase Shift Keying (DPSK, Quadrature Phase Shift Keying (QPSK, 16-Quadrature Amplitude Modulation (QAM and 64-QAM that dramatically enhance the telecom signal spectral efficiency, paving the way to next generation terabit all-optical networks.
Space vehicle pose estimation via optical correlation and nonlinear estimation
Rakoczy, John M.; Herren, Kenneth A.
2008-03-01
A technique for 6-degree-of-freedom (6DOF) pose estimation of space vehicles is being developed. This technique draws upon recent developments in implementing optical correlation measurements in a nonlinear estimator, which relates the optical correlation measurements to the pose states (orientation and position). For the optical correlator, the use of both conjugate filters and binary, phase-only filters in the design of synthetic discriminant function (SDF) filters is explored. A static neural network is trained a priori and used as the nonlinear estimator. New commercial animation and image rendering software is exploited to design the SDF filters and to generate a large filter set with which to train the neural network. The technique is applied to pose estimation for rendezvous and docking of free-flying spacecraft and to terrestrial surface mobility systems for NASA's Vision for Space Exploration. Quantitative pose estimation performance will be reported. Advantages and disadvantages of the implementation of this technique are discussed.
E Heebner, John; Boyd, Robert W; Park, Q-Han
2002-03-01
We describe an optical transmission line that consists of an array of wavelength-scale optical disk resonators coupled to an optical waveguide. Such a structure leads to exotic optical characteristics, including ultraslow group velocities of propagation, enhanced optical nonlinearities, and large dispersion with a controllable magnitude and sign. This device supports soliton propagation, which can be described by a generalized nonlinear Schrodinger equation.
Optical nonlinearity for few-photon pulses on a quantum dot-pillar cavity device
Loo, Vivien; Gazzano, Olivier; Lemaitre, Aristide; Sagnes, Isabelle; Krebs, Olivier; Voisin, Paul; Senellart, Pascale; Lanco, Loïc
2012-01-01
Giant optical nonlinearity is observed under both continuous-wave and pulsed excitation in a deterministically-coupled quantum dot-micropillar system, in a pronounced strong-coupling regime. Using absolute reflectivity measurements we determine the critical intracavity photon number as well as the input and output coupling efficiencies of the device. Thanks to a near-unity input-coupling efficiency, we demonstrate a record nonlinearity threshold of only 8 incident photons per pulse. The output-coupling efficiency is found to strongly influence this nonlinearity threshold. We show how the fundamental limit of single-photon nonlinearity can be attained in realistic devices, which would provide an effective interaction between two coincident single photons.
Stiripentol kinetics in epilepsy: nonlinearity and interactions.
Levy, R H; Loiseau, P; Guyot, M; Blehaut, H M; Tor, J; Moreland, T A
1984-11-01
Stiripentol kinetics during oral therapy were assessed in six patients with epilepsy who were receiving other antiepileptic drugs. Steady-state levels at 600, 1200, and 2400 mg/day increased in a nonlinear fashion, indicating Michaelis-Menten kinetics. Oral clearance of stiripentol at 600 mg/day was 41.5 +/- 23.4 l/day/kg (mean +/- SD), greater than that at 1200 mg/day (20.3 +/- 8.8 l/day/kg; P less than 0.05) or 2400 mg/day (8.5 +/- 3.8 l/day/kg; P less than 0.01). The apparent in vivo Michaelis-Menten parameters were determined from three mean steady-state concentrations. The average velocity of conversion of stiripentol to its metabolites (Vm), Michaelis constant (Km), and the ratio Vm/Km were 49.3 +/- 13.1 mg/day/kg, 1.35 +/- 1.08 mg/l, and 50.2 +/- 27.5 l/day/kg. Stiripentol reduced the elimination clearances of concomitant antiepileptic drugs. Phenytoin clearance was reduced in all five subjects who received this drug, from a mean control of 29.5 +/- 13.4 l/day to 18.5 +/- 4.6 l/day at a stiripentol dose of 1200 mg/day (P = 0.05) and to 6.48 +/- 2.59 l/day at 2400 mg/day (P less than 0.01). Stiripentol reduced the clearance of carbamazepine in one subject from a control value of 209 l/day to 128 l/day (1200 mg/day) and 61 l/day (2400 mg/day). Stiripentol reduced phenobarbital clearance in two subjects from 3.8 and 5.1 l/day to 2.3 and 3.4 l/day (2400 mg/day). The Michaelis-Menten kinetics of stiripentol, as well as its interactions with other antiepileptic drugs, have important implications in the designing of controlled clinical trials.
Fiber-coupled nanophotonic devices for nonlinear optics and cavity QED
Barclay, Paul Edward
2007-10-01
The sub-wavelength optical confinement and low optical loss of nanophotonic devices dramatically enhances the interaction between light and matter within these structures. When nanophotonic devices are combined with an efficient optical coupling channel, nonlinear optical behavior can be observed at low power levels in weakly-nonlinear materials. In a similar vein, when resonant atomic systems interact with nanophotonic devices, atom-photon coupling effects can be observed at a single quanta level. Crucially, the chip based nature of nanophotonics provides a scalable platform from which to study these effects. This thesis addresses the use of nanophotonic devices in nonlinear and quantum optics, including device design, optical coupling, fabrication and testing, modeling, and integration with more complex systems. We present a fiber taper coupling technique that allows efficient power transfer from an optical fiber into a photonic crystal waveguide. Greater than 97% power transfer into a silicon photonic crystal waveguide is demonstrated. This optical channel is then connected to a high-Q (> 40,000), ultra-small mode volume (V 44% of the photons input to a fiber. This permits the observation of optical bistability in silicon for sub-mW input powers at telecommunication wavelengths. To port this technology to cavity QED experiments at near-visible wavelengths, we also study silicon nitride microdisk cavities at wavelengths near 852 nm, and observe resonances with Q > 3 million and V device with an atom chip, creating an "atom-cavity chip" which can magnetically trap laser cooled atoms above the microcavity. Calculations of the microcavity single atom sensitivity as a function of Q/V are presented and compared with numerical simulations. Taking into account non-idealities, these cavities should allow detection of single laser cooled cesium atoms.
Second-order nonlinear optical metamaterials: ABC-type nanolaminates
Energy Technology Data Exchange (ETDEWEB)
Alloatti, L., E-mail: alloatti@mit.edu; Kieninger, C.; Lauermann, M.; Köhnle, K. [Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Froelich, A.; Wegener, M. [Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); Frenzel, T. [Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Freude, W. [Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Institute for Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany); Leuthold, J.; Koos, C., E-mail: christian.koos@kit.edu [Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Institute for Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany)
2015-09-21
We demonstrate a concept for second-order nonlinear metamaterials that can be obtained from non-metallic centrosymmetric constituents with inherently low optical absorption. The concept is based on iterative atomic-layer deposition of three different materials, A = Al{sub 2}O{sub 3}, B = TiO{sub 2}, and C = HfO{sub 2}. The centrosymmetry of the resulting ABC stack is broken since the ABC and the inverted CBA sequences are not equivalent—a necessary condition for non-zero second-order nonlinearity. In our experiments, we find that the bulk second-order nonlinear susceptibility depends on the density of interfaces, leading to a nonlinear susceptibility of 0.26 pm/V at a wavelength of 800 nm. ABC-type nanolaminates can be deposited on virtually any substrate and offer a promising route towards engineering of second-order optical nonlinearities at both infrared and visible wavelengths.
Nonlinear Optical Parameters of Magnetoactive Semiconductor-Plasmas
Singh, M.; Joseph, D.; Duhan, S.
The nonlinear optical parameters (absorption coefficient and refractive index) of semiconductor-plasmas subjected to a transverse magnetic field have been investigated analytically. By employing the coupled-mode scheme, an expression of third-order optical susceptibility and resultant nonlinear absorption and refractive index of the medium are obtained. The analysis has been applied to both cases, viz., centrosymmetric (β = 0) and noncentrosymmetric (β ≠ 0) in the presence of magnetic field. The numerical estimates are made for InSb crystal at liquid nitrogen temperature duly irradiated by a 10-nanosecond pulsed 10.6 μm CO2 laser. The influence of doping concentration and magnetic field on both the nonlinear absorption and refractive index has been explored, and the results are found to be well in agreement with theory and experiment. Analysis further establishes that absorption coefficient and refractive index can be controlled with precision in semiconductors by the proper selection of doping concentration and an external magnetic field, and hence these media may be used for fabrication of fast cubic nonlinear optical devices under off-resonant transition regime.
Deterministic quantum nonlinear optics with single atoms and virtual photons
Kockum, Anton Frisk; Miranowicz, Adam; Macrı, Vincenzo; Savasta, Salvatore; Nori, Franco
2017-06-01
We show how analogs of a large number of well-known nonlinear-optics phenomena can be realized with one or more two-level atoms coupled to one or more resonator modes. Through higher-order processes, where virtual photons are created and annihilated, an effective deterministic coupling between two states of such a system can be created. In this way, analogs of three-wave mixing, four-wave mixing, higher-harmonic and -subharmonic generation (i.e., up- and down-conversion), multiphoton absorption, parametric amplification, Raman and hyper-Raman scattering, the Kerr effect, and other nonlinear processes can be realized. In contrast to most conventional implementations of nonlinear optics, these analogs can reach unit efficiency, only use a minimal number of photons (they do not require any strong external drive), and do not require more than two atomic levels. The strength of the effective coupling in our proposed setups becomes weaker the more intermediate transition steps are needed. However, given the recent experimental progress in ultrastrong light-matter coupling and improvement of coherence times for engineered quantum systems, especially in the field of circuit quantum electrodynamics, we estimate that many of these nonlinear-optics analogs can be realized with currently available technology.
(DARPA) Nonlinear Optics at Low Light Levels
2010-05-28
Stokes and anti-Stokes photons are transmitted through 10 GHz electro- optic amplitude modulators ( Eospace Inc.) with a half-wave voltage, Vπ of 1.3V. To...sinusoidal phase modulators ( EOSPACE ) which are driven at 30 GHz with modulation depths of about 1.5 radians. To set the modulation depth, we adjust...variable attenuator, (e) Atm Inc. P1409-360 phase trimmer, (f) Nextec-RF NA00435 amplifiers, (g) MegaPhase CA- V1K2 K to V coaxial adapters, (h) EOSPACE
Effects of graphene quantum dots on linear and nonlinear optical behavior of malignant ovarian cells
Mohajer, Salman; Ara, Mohammad Hossein Majles; Serahatjoo, Leila
2016-07-01
We investigate linear and nonlinear optical properties of standard human ovarian cancer cells (cell line: A2780cp) in vitro. Cells were treated by graphene quantum dots (GQDs) with two special concentrations. Nontoxicity of GQDs was examined in standard biological viability tests. Cancerous cells were fixed on a glass slide; then, interaction of light with biofilms was studied in linear and nonlinear regimes. Absorption spectra of untreated biofilms and biofilms with two different concentrations of GQDs was studied by UV-visible spectrophotometer. Optical behavior of biofilms in a linear regime of intensity (with low-intensity laser exposure) was reported using a simple optical setup. After that, we compared the attenuation of light in biofilm of cancerous cells with and without GQDs. Nonlinear behavior of these biofilms was investigated by a Z-scan setup using a continued wave He-Ne laser. Results showed that GQDs decreased the extinction coefficient and changed the sign and exact value of the nonlinear refractive index of malignant ovarian cells noticeably. The nonlinear refractive index of studied cells with no GQDs treatment was in the order of 10-8 (cm2/w) with a positive sign. This quantity changed to the same order of magnitude with a negative sign after GQDs treatment. Thus, GQDs can be used for cancer diagnosis under laser irradiation.
Hirooka, Toshihiko; Seya, Daiki; Harako, Koudai; Suzuki, Daiki; Nakazawa, Masataka
2015-08-10
We propose the ultrahigh-speed demultiplexing of Nyquist OTDM signals using an optical Nyquist pulse as both a signal and a sampling pulse in an all-optical nonlinear switch. The narrow spectral width of the Nyquist pulses means that the spectral overlap between data and control pulses is greatly reduced, and the control pulse itself can be made more tolerant to dispersion and nonlinear distortions inside the nonlinear switch. We apply the Nyquist control pulse to the 640 to 40 Gbaud demultiplexing of DPSK and DQPSK signals using a nonlinear optical loop mirror (NOLM), and demonstrate a large performance improvement compared with conventional Gaussian control pulses. We also show that the optimum spectral profile of the Nyquist control pulse depends on the walk-off property of the NOLM.
Self-characterization of linear and nonlinear adaptive optics systems
Hampton, Peter J.; Conan, Rodolphe; Keskin, Onur; Bradley, Colin; Agathoklis, Pan
2008-01-01
We present methods used to determine the linear or nonlinear static response and the linear dynamic response of an adaptive optics (AO) system. This AO system consists of a nonlinear microelectromechanical systems deformable mirror (DM), a linear tip-tilt mirror (TTM), a control computer, and a Shack-Hartmann wavefront sensor. The system is modeled using a single-input-single-output structure to determine the one-dimensional transfer function of the dynamic response of the chain of system hardware. An AO system has been shown to be able to characterize its own response without additional instrumentation. Experimentally determined models are given for a TTM and a DM.
In vivo multimodal nonlinear optical imaging of mucosal tissue
Sun, Ju; Shilagard, Tuya; Bell, Brent; Motamedi, Massoud; Vargas, Gracie
2004-05-01
We present a multimodal nonlinear imaging approach to elucidate microstructures and spectroscopic features of oral mucosa and submucosa in vivo. The hamster buccal pouch was imaged using 3-D high resolution multiphoton and second harmonic generation microscopy. The multimodal imaging approach enables colocalization and differentiation of prominent known spectroscopic and structural features such as keratin, epithelial cells, and submucosal collagen at various depths in tissue. Visualization of cellular morphology and epithelial thickness are in excellent agreement with histological observations. These results suggest that multimodal nonlinear optical microscopy can be an effective tool for studying the physiology and pathology of mucosal tissue.
Modelling of Nonlinear Dynamic of Mechanic Systems with the Force Tribological Interaction
Directory of Open Access Journals (Sweden)
K.A. Nuzhdin
2015-09-01
Full Text Available This paper considers the mechanisms with different structure: tribometric device and a mechanism for handling of optical glasses. In the first device, the movement of the upper platform is due to a reciprocating friction interaction. In the second device, the processing of the optical element or group of elements occurs due to the rotational motion. Modelling of the dynamic of these systems with Matlab/Simmechanic allowed carrying out the analysis of dynamic of mechanisms, considering nonlinearity tribological interactions for these systems. The article shows that using of the computer models can effectively carry out the selection of the control parameters to create the desired mode of operation, as well as to investigate the behaviour of systems with nonlinear parameters and processes of self-oscillations. The organization of the managed self-oscillation process is realized to create the relevant high-performance manufacturing, for example, for the processing of optical glasses.
Phase stabilization of Kerr frequency comb internally without nonlinear optical interferometry
Huang, S -W; Yang, J; Yu, M; Kwong, D -L; Wong, C W
2016-01-01
Optical frequency comb (OFC) technology has been the cornerstone for scientific breakthroughs such as precision frequency metrology, redefinition of time, extreme light-matter interaction, and attosecond sciences. While the current mode-locked laser-based OFC has had great success in extending the scientific frontier, its use in real-world applications beyond the laboratory setting remains an unsolved challenge. Microresonator-based OFCs, or Kerr frequency comb, have recently emerged as a candidate solution to the challenge because of their preferable size, weight, and power consumption (SWaP). On the other hand, the current phase stabilization technology requires either external optical references or power-demanding nonlinear processes, overturning the SWaP benefit of Kerr frequency combs. Introducing a new concept in phase control, here we report an internally phase stabilized Kerr frequency comb without the need of any optical references or nonlinear processes. We describe the comb generation analytically ...
Nonlinear optical studies of relaxation in semiconductor microstructures
Remillard, Jeffrey Thomas
1990-11-01
Exposing a semiconductor to optical radiation near the fundamental band gap results in the creation of populations or elementary excitations including electrons, holes, and excitons, and also results in the creation of a superposition state between the ground and excited state of the solid. The relaxation of optically generated excitons and carriers in semiconductor microstructures was studied using four wave mixing (FWM) spectroscopy. The systems studied include CdSSe microcrystallite doped glasses and GaA/AlGaAs multiple quantum well structures (MQWS). First, the nonlinear optical response of simple two level systems is examined in order to provide insight into the types of line shapes expected from semiconductors. It is shown that the line shape is strongly dependent on how the system is coupled to the reservoir and the consequences of coupling to a reservoir are examined in a FWM measurement made in atomic sodium. The first semiconductor system studied is CdSSe microcrystallite doped glass. This system is shown to have a very slow component to the nonlinear response which has an optical intensity dependence and temperature dependence which suggests that the FWM response in these materials is trap mediated. Room temperature FWM measurements in GaAs MQWS enables the measurement of the carrier recombination time and the ambipolar diffusion coefficient. Using the technique of correlated optical fields, a slow component to the nonlinear response was measured showing an interference profile which suggests a possible shift of the exciton resonance due to the optically generated carriers. At low temperatures, measurements of the exciton line shape and relaxation time were made and evidence for exciton spectral diffusion was found. The low temperature line shapes can be qualitatively reproduced using Modified Optical Bloch equations which include the effects of spectral diffusion.
Nonlinear Quantum Optical Springs and Their Nonclassical Properties
Institute of Scientific and Technical Information of China (English)
M.J. Faghihi; M.K. Tavassoly
2011-01-01
The original idea of quantum optical spring arises from the requirement of quantization of the frequency of oscillations in the Hamiltonian of harmonic oscillator. This purpose is achieved by considering a spring whose constant （and so its frequency） depends on the quantum states ofanother system. Recently, it is realized that by the assumption of frequency modulation of ω to ω √1＋ μα＋α the mentioned idea can be established. In the present paper, we generalize the approach of quantum optical spring with particular attention to the dependence or trequency to the intensity of radiation field that naturally observes in the nonlinear coherent states, from which we arrive at a physical system has been called by us as nonlinear quantum optical spring. Then, after the introduction of the generalized tlamiltonian of nonlinear quantum optical spring and it＇s solution, we will investigate the nonclassical properties of the obtained states. Specially, typical collapse and revival in the distribution functions and squeezing parameters, as particular quantum features, will be revealed.
Ablation and optical third-order nonlinearities in Ag nanoparticles
Directory of Open Access Journals (Sweden)
Carlos Torres-Torres
2010-11-01
Full Text Available Carlos Torres-Torres1, Néstor Peréa-López2, Jorge Alejandro Reyes-Esqueda3, Luis Rodríguez-Fernández3, Alejandro Crespo-Sosa3, Juan Carlos Cheang-Wong3, Alicia Oliver31Section of Graduate Studies and Research, School of Mechanical and Electrical Engineering, National Polytechnic Institute, Zacatenco, Distrito Federal, Mexico; 2Laboratory for Nanoscience and Nanotechnology Research and Advanced Materials Department, IPICYT, Camino a la Presa San Jose, San Luis Potosi, Mexico; 3Instituto de Física, Universidad Nacional Autónoma de México, A.P. 20-364, México, D.F. 01000, MéxicoAbstract: The optical damage associated with high intensity laser excitation of silver nanoparticles (NPs was studied. In order to investigate the mechanisms of optical nonlinearity of a nanocomposite and their relation with its ablation threshold, a high-purity silica sample implanted with Ag ions was exposed to different nanosecond and picosecond laser irradiations. The magnitude and sign of picosecond refractive and absorptive nonlinearities were measured near and far from the surface plasmon resonance (SPR of the Ag NPs with a self-diffraction technique. Saturable optical absorption and electronic polarization related to self-focusing were identified. Linear absorption is the main process involved in nanosecond laser ablation, but nonlinearities are important for ultrashort picosecond pulses when the absorptive process become significantly dependent on the irradiance. We estimated that near the resonance, picosecond intraband transitions allow an expanded distribution of energy among the NPs, in comparison to the energy distribution resulting in a case of far from resonance, when the most important absorption takes place in silica. We measured important differences in the ablation threshold and we estimated that the high selectiveness of the SPR of Ag NPs as well as their corresponding optical nonlinearities can be strongly significant for laser
Nonlinear optics with coherent free electron lasers
Bencivenga, F.; Capotondi, F.; Mincigrucci, R.; Cucini, R.; Manfredda, M.; Pedersoli, E.; Principi, E.; Simoncig, A.; Masciovecchio, C.
2016-12-01
We interpreted the recent construction of free electron laser (FELs) facilities worldwide as an unprecedented opportunity to bring concepts and methods from the scientific community working with optical lasers into the domain of x-ray science. This motivated our efforts towards the realization of FEL-based wave-mixing applications. In this article we present new extreme ultraviolet transient grating (X-TG) data from vitreous SiO2, collected using two crossed FEL pulses (photon frequency 38 eV) to generate the X-TG and a phase matched optical probing pulse (photon frequency 3.1 eV). This experiment extends our previous investigation, which was carried out on a nominally identical sample using a different FEL photon frequency (45 eV) to excite the X-TG. The present data are featured by a peak intensity of the X-TG signal substantially larger than that previously reported and by slower modulations of the X-TG signal at positive delays. These differences could be ascribed to the different FEL photon energy used in the two experiments or to differences in the sample properties. A systematic X-TG study on the same sample as a function of the FEL wavelength is needed to draw a consistent conclusion. We also discuss how the advances in the performance of the FELs, in terms of generation of fully coherent photon pulses and multi-color FEL emission, may push the development of original experimental strategies to study matter at the femtosecond-nanometer time-length scales, with the unique option of element and chemical state specificity. This would allow the development of advanced experimental tools based on wave-mixing processes, which may have a tremendous impact in the study of a large array of phenomena, ranging from nano-dynamics in complex materials to charge and energy transfer processes.
Intrinsic optical bistability between left-handed material and nonlinear optical materials
Institute of Scientific and Technical Information of China (English)
Shi Hong-Yan; Jiang Yong-Yuan; Sun Xiu-Dong; Guo Ru-Hai; Zhao Yi-Ping
2005-01-01
The electromagnetic properties of the interface between a left-handed material and a conventional nonlinear material were investigated theoretically and numerically. We found a new phenomenon-optical bistability of the interface.It was shown that the incident intensity, incident angle and permeability ratio between the left-handed and the nonlinear materials could dramatically affect the optical bistable behaviour. We also compared the bistable behaviours of different electromagnetic modes. The results indicated that the TE mode was prior to the TM mode to obtain optical bistability for the same parameter.
Directory of Open Access Journals (Sweden)
Anju K. Augustine
2014-01-01
Full Text Available We present third-order optical nonlinear absorption in CdSe quantum dots (QDs with particle sizes in the range of 4.16–5.25 nm which has been evaluated by the Z-scan technique. At an excitation irradiance of 0.54 GW/cm2 the CdSe QDs exhibit reverse saturation indicating a clear nonlinear behavior. Nonlinearity increases with particle size in CdSe QDs within the range of our investigations which in turn depends on the optical band gap. The optical limiting threshold of the QDs varies from 0.35 GW/cm2 to 0.57 GW/cm2 which makes CdSe QDs a promising candidate for reverse-saturable absorption based devices at high laser intensities such as optical limiters.
Nonlinear optical properties and optical limiting measurements of graphene oxide - Ag@TiO2 compounds
Ebrahimi, M.; Zakery, A.; Karimipour, M.; Molaei, M.
2016-07-01
In this work Graphene Oxide (GO), Ag@TiO2 core-shells and GO-Ag@TiO2 compounds were prepared and experimentally verified. Using a low power laser diode with 532 nm wavelength, the magnitude and the sign of the nonlinear refractive index and nonlinear absorption were determined by the Z-scan technique. It was observed that the nonlinear absorption of GO-Ag@TiO2 mixture was higher than pure GO. The optical limiting effect of these samples was also investigated using the 2nd harmonics of a pulsed Nd-YAG laser at 532 nm. Our results showed that the sole Ag@TiO2 didn't show any appreciable optical limiting effect, however after just mixing with graphene oxide the threshold of optical limiting was increased and the compound showed an enhancement of optical limiting behavior compared to GO itself. The presented results are discussed and compared with other literature reports.
Zhao, Peng; Wang, Zonghua; Chen, Jishi; Zhou, Yu; Zhang, Fushi
2017-04-01
The nonlinear optical properties of the polymeric carboxyl phthalocyanine with lanthanum (LaPPc.COOH), holmium (HoPPc.COOH) and ytterbium (YbPPc.COOH) as centric atom, were investigated by the Z-scan method using a picosecond 532 nm laser. The synthesized phthalocyanines had steric polymeric structure and dissolved well in aqueous solution. The nonlinear optical response of them was attributed to the reverse saturable absorption and self-focus refraction. The nonlinear absorption properties decreased with the centric atoms changing from La, Ho to Yb. The largest second-order hyperpolarizability and optical limiting response threshold of LaPPc.COOH were 3.89 × 10-29 esu and 0.32 J/cm2, respectively. The reverse saturable absorption was explained by a three level mode of singlet excited state under the picosecond irradiation. The result indicates the steric structure presented additive stability of these polymeric phthalocyanines for their application as potential optical limiting materials.
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.
Nonlinear Sensing With Collective States of Ultracold Atoms in Optical Lattices
2015-04-02
decimation algorithm , a method that takes into account quantum correlations. B.1. In collaboration with D. Blume and X.Y. Yin at Washington State...Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 Nonlinear quantum sensing, quantum metrology, ultracold atoms, optical lattices REPORT...with applications to interaction-based quantum metrology, Physical Review A, (10 2014): 0. doi: 10.1103/PhysRevA.90.041602 Khan W Mahmud, Lei Jiang
Nonlinear Optical Properties of Indium Phthalocyanine Axially Grafted Polystyrene Thin Film
Institute of Scientific and Technical Information of China (English)
ZHU Rong-Yi; QIU Xue-Qiong; CHEN Yu; QIAN Shi-Xiong
2006-01-01
@@ Ultrafast dynamics and third-order nonlinearity of thin films of tert-butyl peripherally-substituted indium ph thalocyanine axially grafted polystyrene (tBu4PcIn-PS) are investigated by femtosecond optical-Kerr-effect (OKE) and z-scan experiments. The fastest component (＜ 200 fs) in the OKE traces of the film is related to the electron cloud distortion, where the phthalocyanine-polymer interaction may enhance this contribution.
Large Enhancement of Optical Nonlinearities of New Organophosphorus Fullerene Derivative
Institute of Scientific and Technical Information of China (English)
刘智波; 田建国; 臧维平; 周文远; 张春平; 郑建禺; 周迎春; 徐华
2003-01-01
Optical nonlinearities of new organophosphorus fullerene derivative were determined by the Z-scan method with a pulsed Q-switch Nd:YAG laser at 532nm. The experimental results demonstrated that the derivative has much larger excited-states nonlinear absorption and nonlinear refraction than C60. A five-level model was utilized to fit the experimental data, and a good agreement is reached. Some parameters such as excited-state absorption cross and refraction cross were obtained. To our knowledge, the excited-state cross section of new organophosphorus fullerene derivative and its effective ratio to the ground-state cross section are the largest values among the fullerene derivatives reported to date.
Nonlinear Acoustic Wave Interactions in Layered Media.
1980-03-06
Generated Components in Dispersive Media. . . . . . . . . . . . . 62 4.4 Dispersion in Medium II . . . . . . . . .. 68 V. CONCLUSIONS...give rise to leaky wave modes which are more thoroughly discussed 17 18 by Kapany and Burke, and by Marcuse . Leaky modes are C.C. Ghizoni, J.M...1977), 843-848. 1 7N.S. Kapany and J.J. Burke, Optical Waveeeuides, (New York: Academic Press, 1972), pp. 24-34. D. Marcuse , Theory of Dielectric Optical
Preparation of the Inclusion Complex-Type Nonlinear Optical Polymer
Directory of Open Access Journals (Sweden)
Li-Fen Wang
2013-01-01
Full Text Available This study uses the inclusion complex method to import nonlinear optical (NLO chromophores, disperse red1 (DR1, and spiropyran (SP, into the γ-CD cavity of the γ-cyclodextrin polymer (γ-CDP to prepare orderly aligned nonphotocontrollable and photocontrollable nonlinear optical polymers. Calculations support the ultraviolet/visible analyses and suggest the formation of the 1 : 2 DR1/γ-CDP and 1 : 2 SP/γ-CDP inclusion complexes. Upon complexation, the DR1 and SP molecules are free to align themselves along an applied electric field and show high order parameters of approximately 0.48 and 0.20, respectively. Reversible photochromic reactions exhibit that the SP/γ-CDP complex still retains the photochromic properties following corona poling.
Chromatic and Dispersive Effects in Nonlinear Integrable Optics
Webb, Stephen D; Valishev, Alexander; Nagaitsev, Sergei N; Danilov, Viatcheslav V
2015-01-01
Proton accumulator rings and other circular hadron accelerators are susceptible to intensity-driven parametric instabilities because the zero-current charged particle dynamics are characterized by a single tune. Landau damping can suppress these instabilities, which requires energy spread in the beam or introducing nonlinear magnets such as octupoles. However, this approach reduces dynamic aperture. Nonlinear integrable optics can suppress parametric instabilities independent of energy spread in the distribution, while preserving the dynamic aperture. This novel approach promises to reduce particle losses and enable order-of-magnitude increases in beam intensity. In this paper we present results, obtained using the Lie operator formalism, on how chromaticity and dispersion affect particle orbits in integrable optics. We conclude that chromaticity in general breaks the integrability, unless the vertical and horizontal chromaticities are equal. Because of this, the chromaticity correcting magnets can be weaker ...
Nonlinear optical polarization analysis in chemistry and biology
Simpson, Garth J
2017-01-01
This rigorous yet accessible guide presents a molecular-based description of nonlinear optical polarization analysis of chemical and biological assemblies. It includes discussion of the most common nonlinear optical microscopy and interfacial measurements used for quantitative analysis, specifically second harmonic generation (SHG), two-photon excited fluorescence (2PEF), vibrational sum frequency generation (SFG), and coherent anti-Stokes Raman spectroscopy/stimulated Raman spectroscopy (CARS/SRS). A linear algebra mathematical framework is developed, allowing step-wise systematic connections to be made between the observable measurements and the molecular response. Effects considered include local field corrections, the molecular orientation distribution, rotations between the molecular frame, the local frame and the laboratory frame, and simplifications from molecular and macromolecular symmetry. Specific examples are provided throughout the book, working from the common and relatively simple case studies ...
Parametric Analysis of Fiber Non-Linearity in Optical systems
Directory of Open Access Journals (Sweden)
Abhishek Anand
2013-06-01
Full Text Available With the advent of technology Wavelength Division Multiplexing (WDM is always an area of interest in the field of optical communication. When combined with Erbium Doped Fiber Amplifier (EDFA, it provides high data transmission rate and low attenuation. But due to fiber non-linearity such as Self Phase Modulation (SPM and Cross Phase Modulation (XPM the system performance has degraded. This non-linearity depends on different parameters of an optical system such as channel spacing, power of the channel and length of the fiber section. The degradation can be seen in terms of phase deviation and Bit Error Rate (BER performance. Even after dispersion compensation at the fiber end, residual pulse broadening still exists due to cross talk penalty.
ZnS/PVA nanocomposites for nonlinear optical applications
Ozga, K.; Michel, J.; Nechyporuk, B. D.; Ebothé, J.; Kityk, I. V.; Albassam, A. A.; El-Naggar, A. M.; Fedorchuk, A. O.
2016-07-01
We have found a correlation between ZnS nanocomposite nonlinear optical features and technological processing using electrolytic method. In the earlier researches this factor was neglected. However, it may open a new stage for operation by photovoltaic features of the well known semiconductors within a wide range of magnitudes. The titled nanostructured zinc sulfide (ZnS) was synthesized by electrolytic method. The obtained ZnS nano-crystallites possessed nano-particles sizes varying within 1.6 nm…1.8 nm. The titled samples were analyzed by XRD, HR-TEM, STEM, and nonlinear optical methods such as photo-induced two-photon absorption (TPA) and second harmonic generation (SHG). For this reason the nano-powders were embedded into the photopolymer poly(vinyl) alcohol (PVA) matrices. Role of aggregation in the mentioned properties is discussed. Possible origin of the such correlations are discussed.
Dynamic nonlinear thermal optical effects in coupled ring resonators
Directory of Open Access Journals (Sweden)
Chenguang Huang
2012-09-01
Full Text Available We investigate the dynamic nonlinear thermal optical effects in a photonic system of two coupled ring resonators. A bus waveguide is used to couple light in and out of one of the coupled resonators. Based on the coupling from the bus to the resonator, the coupling between the resonators and the intrinsic loss of each individual resonator, the system transmission spectrum can be classified by three different categories: coupled-resonator-induced absorption, coupled-resonator-induced transparency and over coupled resonance splitting. Dynamic thermal optical effects due to linear absorption have been analyzed for each category as a function of the input power. The heat power in each resonator determines the thermal dynamics in this coupled resonator system. Multiple “shark fins” and power competition between resonators can be foreseen. Also, the nonlinear absorption induced thermal effects have been discussed.
Nonlinear interface optical switch structure for dual mode switching revisited
Bussjager, Rebecca J.; Osman, Joseph M.; Chaiken, Joseph
1998-07-01
There is a need for devices which will allow integration of photonic/optical computing subsystems into electronic computing architectures. This presentation reviews the nonlinear interface optical switch (NIOS) concept and then describes a new effect, the erasable optical memory (EOM) effect. We evaluate an extension of the NIOS device to allow simultaneous optical/electronic, i.e. dual mode, switching of light utilizing the EOM effect. Specific devices involve the fabrication of thin film tungsten (VI) oxide (WO3) and tungsten (V) oxide (W2O5) on the hypotenuse of glass (BK-7), fused silica (SiO2) and zinc selenide (ZnSe) right angle prisms. Chemical reactions and temporal response tests were performed and are discussed.
Nonlinear random optical waves: Integrable turbulence, rogue waves and intermittency
Randoux, Stéphane; Walczak, Pierre; Onorato, Miguel; Suret, Pierre
2016-10-01
We examine the general question of statistical changes experienced by ensembles of nonlinear random waves propagating in systems ruled by integrable equations. In our study that enters within the framework of integrable turbulence, we specifically focus on optical fiber systems accurately described by the integrable one-dimensional nonlinear Schrödinger equation. We consider random complex fields having a Gaussian statistics and an infinite extension at initial stage. We use numerical simulations with periodic boundary conditions and optical fiber experiments to investigate spectral and statistical changes experienced by nonlinear waves in focusing and in defocusing propagation regimes. As a result of nonlinear propagation, the power spectrum of the random wave broadens and takes exponential wings both in focusing and in defocusing regimes. Heavy-tailed deviations from Gaussian statistics are observed in focusing regime while low-tailed deviations from Gaussian statistics are observed in defocusing regime. After some transient evolution, the wave system is found to exhibit a statistically stationary state in which neither the probability density function of the wave field nor the spectrum changes with the evolution variable. Separating fluctuations of small scale from fluctuations of large scale both in focusing and defocusing regimes, we reveal the phenomenon of intermittency; i.e., small scales are characterized by large heavy-tailed deviations from Gaussian statistics, while the large ones are almost Gaussian.
Computationally Efficient Nonlinearity Compensation for Coherent Fiber-Optic Systems
Institute of Scientific and Technical Information of China (English)
Likai Zhu; Guifang Li
2012-01-01
Split-step digital backward propagation (DBP) can be combined with coherent detection to compensate for fiber nonlinear impairments. A large number of DBP steps is usually needed for a long-haul fiber system, and this creates a heavy computational load. In a trade-off between complexity and performance, interchannel nonlinearity can be disregarded in order to simplify the DBP algorithm. The number of steps can also be reduced at the expense of performance. In periodic dispersion-managed long-haul transmission systems, optical waveform distortion is dominated by chromatic dispersion. As a result, the nonlinearity of the optical signal repeats in every dispersion period. Because of this periodic behavior, DBP of many fiber spans can be folded into one span. Using this distance-folded DBP method, the required computation for a transoceanic transmission system with full inline dispersion compensation can be reduced by up to two orders of magnitude with negligible penalty. The folded DBP method can be modified to compensate for nonlinearity in fiber links with non-zero residua dispersion per span.
Nonlinear optical properties of methyl red under CW irradiation
Zheng, Yu; Ye, Qing; Wang, Chen; Wang, Jin; Deng, Zhichao; Mei, Jianchun; Zhou, Wenyuan; Zhang, Chunping; Tian, Jianguo
2015-12-01
Organic materials have wide potential application in nonlinear optical devices. The nonlinear optical (NLO) properties of methyl red (MR) doped polymethyl methacrylate (MR-PMMA) are investigated under CW laser irradiation at 473 nm, 532 nm and 632.8 nm, respectively. By combining Kramers-Kronig (K-K) relation and CW Z-scan technique, the effective refractive index n2 and the change of refractive index Δn are obtained under different scanning speed at 473 nm and 532 nm. Δn is positive at 473 nm, while Δn is negative at 532 nm. The experimental result is consistent with that of K-K relation. With the scanning speed decreasing, the NLO properties of MR-PMMA are enhanced. With different laser powers at 632.8 nm, MR-PMMA has only nonlinear absorption rather than nonlinear refraction. Meanwhile, the sample is investigated under pulse laser irradiation at 532 nm. Through the comparison of results of CW Z-scan and pulse Z-scan, the influence of the cumulative thermal effect on NLO properties of material is investigated. The results indicate that, under CW irradiation near the absorption peak wavelength, the cumulative thermal effect has great influence to the NLO properties of MR-PMMA.
Femtosecond nonlinear fiber optics in the ionization regime.
Hölzer, P; Chang, W; Travers, J C; Nazarkin, A; Nold, J; Joly, N Y; Saleh, M F; Biancalana, F; Russell, P St J
2011-11-11
By using a gas-filled kagome-style photonic crystal fiber, nonlinear fiber optics is studied in the regime of optically induced ionization. The fiber offers low anomalous dispersion over a broad bandwidth and low loss. Sequences of blueshifted pulses are emitted when 65 fs, few-microjoule pulses, corresponding to high-order solitons, are launched into the fiber and undergo self-compression. The experimental results are confirmed by numerical simulations which suggest that free-electron densities of ∼10(17) cm(-3) are achieved at peak intensities of 10(14) W/cm(2) over length scales of several centimeters.
Optical detection of terahertz using nonlinear parametric upconversion.
Khan, M Jalal; Chen, Jerry C; Kaushik, Sumanth
2008-12-01
We extend our work to perform sensitive, room-temperature optical detection of terahertz (THz) by using nonlinear parametric upconversion. THz radiation at 700 GHz is mixed with pump light at 1,550 nm in a bulk GaAs crystal to generate an idler wave at 1,555.6 nm. The idler is separated, coupled into optical fiber, and detected using a gated Geiger-mode avalanche photodiode. The resulting THz detector has a power sensitivity of 4.5 pW/Hz and a timing resolution of 1 ns.
Nonlinear optical properties of atomic vapor and semiconductors
Energy Technology Data Exchange (ETDEWEB)
Kim, Doseok [Univ. of California, Berkeley, CA (United States). Dept. of Physics
1997-05-01
This thesis contains the study of highly forbidden resonant second harmonic generation (SHG) in atomic potassium vapor using tunable picosecond pulses. Various output characteristics of vapor SHG have been investigated including the input intensity dependence, potassium vapor density dependence, buffer gas pressure dependence, and spatial profile. Recently, the discovery of new nonlinear optical crystals such as barium borate (β-BaB_{2}O_{4}, BBO) and lithium borate (LiB_{3}O_{5}, LBO) has greatly improved the performance of a tunable coherent optical devices based on optical parametric generation and amplification. In the second part of this thesis, a homebuilt picosecond optical parametric generator/amplifier (OPG/OPA) system is described in detail, including its construction details and output characteristics. This laser device has found many useful applications in spectroscopic studies including surface nonlinear optical spectroscopy via sum-frequency generation (SFG). The last part of this thesis reports studies on multiphoton-excited photoluminescence from porous silicon and GaN. Multiphoton excitation and photoluminescence can give numerous complementary information about semiconductors not obtainable with one-photon, above-bandgap excitation.
Photonic Integrated Devices for Nonlinear Optics
Caspani, Lucia; Dolgaleva, Ksenia; Wagner, Sean; Ferrera, Marcello; Razzari, Luca; Pasquazi, Alessia; Peccianti, Marco; Moss, David J; Aitchison, J Stewart; Morandotti, Roberto
2014-01-01
We review our recent progresses on frequency conversion in integrated devices, focusing primarily on experiments based on strip-loaded and quantum-well intermixed AlGaAs waveguides, and on CMOS-compatible high-index doped silica glass waveguides. The former includes both second- and third-order interactions, demonstrating wavelength conversion by tunable difference-frequency generation over a bandwidth of more than nm, as well as broadband self-phase modulation and tunable four-wave mixing. The latter includes four-wave mixing using low-power continuous-wave light in microring resonators as well as hyper-parametric oscillation in a high quality factor resonator, towards the realization of an integrated multiple wavelength source with important applications for telecommunications, spectroscopy, and metrology.
Dispersion and polarization dependence of mobile carrier optical nonlinearities
Rustagi, K. C.
1984-06-01
Based on the author's earlier work, it is shown that the proper inclusion of carrier scattering should strongly modify the frequency and polarization dependence of optical nonlinearities due to mobile carriers in semiconductors. When the momentum relaxation is much faster than the energy relaxation, the intensity dependent refractive index is enhanced, the induced birefringence becomes a sharp function of the difference frequency ωa-ωb, and a collision induced stimulated Raman effect becomes important.
High field optical nonlinearity and the Kramers-Kronig relations.
Wahlstrand, J K; Cheng, Y-H; Milchberg, H M
2012-09-14
The nonlinear optical response to high fields is absolutely measured for the noble gas atoms He, Ne, Ar, Kr, and Xe. We find that the response is quadratic in the laser field magnitude up to the ionization threshold of each gas. Its size and quadratic dependence are well predicted by a Kramers-Kronig analysis employing known ionization probabilities, and the results are consistent with calculations using the time-dependent Schrödinger equation.
Nonlinear Optical Spectroscopy of Excited States in Polyfluorene
Tong, M; Vardeny, Z V
2006-01-01
We used a variety of nonlinear optical (NLO) spectroscopies to study the singlet excited states order, and primary photoexcitations in polyfluorene; an important blue emitting p-conjugated polymer. The polarized NLO spectroscopies include ultrafast pump-probe photomodulation, two-photon absorption, and electroabsorption. For completeness we also measured the linear absorption and photoluminescence spectra. We found that the primary photoexcitations in polyfluorene are singlet excitons.
Properties of nonreciprocal light propagation in a nonlinear optical isolator
Roy, Dibyendu
2016-01-01
Light propagation in a nonlinear optical medium is nonreciprocal for spatially asymmetric linear permittivity. We here examine physical mechanism and properties of such nonreciprocity (NR). For this, we calculate transmission of light through a two-level atom asymmetrically coupled to light inside open waveguides. We determine the critical intensity of incident light for maximum NR and a dependence of the corresponding NR on asymmetry in the coupling. Surprisingly, we find that it is mainly c...
Chaitanya, N Apurv; Banerji, J; Samanta, G K
2016-01-01
Hollow Gaussian beams (HGB) are a special class of doughnut shaped beams that do not carry orbital angular momentum (OAM). Such beams have a wide range of applications in many fields including atomic optics, bio-photonics, atmospheric science, and plasma physics. Till date, these beams have been generated using linear optical elements. Here, we show a new way of generating HGBs by three-wave mixing in a nonlinear crystal. Based on nonlinear interaction of photons having OAM and conservation of OAM in nonlinear processes, we experimentally generated ultrafast HGBs of order as high as 6 and power >180 mW at 355 nm. This generic concept can be extended to any wavelength, timescales (continuous-wave and ultrafast) and any orders. We show that the removal of azimuthal phase of vortices does not produce Gaussian beam. We also propose a new and only method to characterize the order of the HGBs.
Chaitanya, N. Apurv; Jabir, M. V.; Banerji, J.; Samanta, G. K.
2016-09-01
Hollow Gaussian beams (HGB) are a special class of doughnut shaped beams that do not carry orbital angular momentum (OAM). Such beams have a wide range of applications in many fields including atomic optics, bio-photonics, atmospheric science, and plasma physics. Till date, these beams have been generated using linear optical elements. Here, we show a new way of generating HGBs by three-wave mixing in a nonlinear crystal. Based on nonlinear interaction of photons having OAM and conservation of OAM in nonlinear processes, we experimentally generated ultrafast HGBs of order as high as 6 and power >180 mW at 355 nm. This generic concept can be extended to any wavelength, timescales (continuous-wave and ultrafast) and any orders. We show that the removal of azimuthal phase of vortices does not produce Gaussian beam. We also propose a new and only method to characterize the order of the HGBs.
Optical nonlinearities in semiconductor-doped glasses near and below the band edge
Bindra, K. S.; Oak, S. M.; Rustagi, K. C.
1998-03-01
We present a brief review of our recent experimental results on optical nonlinearities in semiconductor-doped glasses. It is shown that even below the absorption edge the nonlinearities are determined by nonlinear absorption. The optical Kerr effect is found to have a susceptibility which is comparable to that for nonlinear refraction. We also find that in degenerate four-wave mixing the observed intensity dependence can be strongly influenced by nonlinear absorption.
Review of Robust Data Exchange Using Optical Nonlinearities
Directory of Open Access Journals (Sweden)
Jian Wang
2012-01-01
Full Text Available Data exchange, namely bidirectional information swapping, provides enhanced flexibility compared to the unidirectional information transfer. To fulfill the rapid development of high-speed large-capacity optical communications with emerging multiplexing/demultiplexing techniques and advanced modulation formats, a laudable goal would be to achieve data exchange in different degrees of freedom (wavelength, time, polarization, for different modulation formats (OOK, DPSK, DQPSK, pol-muxed, and at different granularities (entire data, groups of bits, tributary channels. Optical nonlinearities are potentially suitable candidates to enable data exchange in the wavelength, time, and polarization domains. In this paper, we will review our recent works towards robust data exchange by exploiting miscellaneous optical nonlinearities, including the use of cSFG/DFG in a PPLN waveguide for time- (groups of bits and channel-selective data exchange and tributary channel exchange between two WDM+OTDM signals, nondegenerate FWM in an HNLF for phase-transparent data exchange (DPSK, DQPSK, bidirectional degenerate FWM in an HNLF for multi-channel data exchange, and Kerr-induced nonlinear polarization rotation in an HNLF for tributary channel exchange of a pol-muxed DPSK OTDM signal. The demonstrated data exchanges in different degrees of freedom, for different modulation formats, and at different granularities, open the door for alternative approaches to achieve superior network performance.
Modulation instability of broad optical beams in nonlinear media with general nonlinearity
Institute of Scientific and Technical Information of China (English)
Hongcheng Wang; Weilong She
2006-01-01
@@ The modulation instability of quasi-plane-wave optical beams is investigated in the frame of generalized Schr(o)dinger equation with the nonlinear term of a general form. General expressions are derived for the dispersion relation, the critical transverse spatial frequency, as well as the instability growth rate.The analysis generalizes the known results reported previously. A detailed discussion on the modulation instability in biased centrosymmetric photorefractive media is also given.
Linear and nonlinear magneto-optics of ferritin.
Pankowska, M; Dobek, A
2009-07-07
Measurements of Rayleigh light scattering and Cotton-Mouton (CM) effect are carried out at room temperature for 100 mM NaCl solutions of apoferritin/ferritin loaded with 0, 90, 100, 500, 700, and 1500 Fe atoms/molecule. Because of the spherical shape, ferritin macromolecule should not manifest magnetic anisotropy; however, in solution it shows the induced magnetic birefringence (CM effect) and changes in intensity of the scattered light components. The newly obtained data support the previously reported conclusions indicating that the deformation of linear optical polarizability induced in the ferritin by a magnetic field and the orientation of the induced magnetic dipole moment by this field are the main sources of the magneto-optical phenomena observed. Nevertheless, it is also found that the orientation of the permanent magnetic dipole moment contributes to both effects. The magnetic field induced changes in the light scattering and the CM effect theoretically depend on the linear magneto-optical polarizability, chi, on the nonlinear magneto-optical polarizability, eta, and square of the permanent magnetic dipole moment value of the macromolecule, mu(2). On the basis of the theory describing both effects as well as the experimental data, the values of the anisotropy of linear magneto-optical polarizabilities components, the values of the linear optical polarizability and its anisotropy, nonlinear magneto-optical polarizability and its anisotropy, are estimated. Also the magnetic dipole moment of the ferritin macromolecule is found. Interestingly, not all iron atoms in the ferritin are indicated to be in the superparamagnetic state, some of them occur in the diamagnetic form.
Ultrafast and Nonlinear Optical Spectroscopy of Carbon Nanotubes
Kono, Junichiro
2011-03-01
Single-walled carbon nanotubes (SWNTs) provide a variety of unique opportunities for studying the dynamics and interactions of one-dimensional (1-D) electrons and phonons. We have carried out a series of ultrafast and nonlinear optical experiments on SWNTs, revealing novel properties of high- density 1-D excitons as well as coherent lattice vibrations. We have shown that there exists an upper limit on the density of 1-D excitons in SWNTs, which results in photoluminescence saturation. Using a model based on diffusion-limited exciton- exciton annihilation, we provided realistic estimates for the exciton densities in the saturation regime. We also predicted and demonstrated that there is an optimum temperature at which the exciton density can be maximized, due to the existence of a dark exciton state. Using ultrashort pulses, we have also investigated the dynamics of coherent phonons (CPs) in SWNTs, including both the low frequency radial breathing mode and high frequency G-mode phonons. Pulse shaping techniques allowed us to generate and detect CPs in SWNTs in a chirality-selective manner, which provided insight into the chirality dependence of light absorption, phonon generation, and phonon-induced band- structure modulations. Finally, we observed novel large- amplitude CPs through near-band-edge excitations as well as strongly polarization-dependent CP signals in highly-aligned SWNTs. This work was performed in collaboration with Y. Murakami, A. Srivastava, T. A. Searles, L. G. Booshehri, E. H. Hároz, D. T. Morris, J.-H. Kim, K.-J. Yee, Y.-S. Lim, G. D. Sanders, C. J. Stanton, and R. Saito.
Inference of a nonlinear stochastic model of the cardiorespiratory interaction
Smelyanskiy, V N; Stefanovska, A; McClintock, P V E
2005-01-01
A new technique is introduced to reconstruct a nonlinear stochastic model of the cardiorespiratory interaction. Its inferential framework uses a set of polynomial basis functions representing the nonlinear force governing the system oscillations. The strength and direction of coupling, and the noise intensity are simultaneously inferred from a univariate blood pressure signal, monitored in a clinical environment. The technique does not require extensive global optimization and it is applicable to a wide range of complex dynamical systems subject to noise.
Polycarbonate-Based Blends for Optical Non-linear Applications
Stanculescu, F.; Stanculescu, A.
2016-02-01
This paper presents some investigations on the optical and morphological properties of the polymer (matrix):monomer (inclusion) composite materials obtained from blends of bisphenol A polycarbonate and amidic monomers. For the preparation of the composite films, we have selected monomers characterised by a maleamic acid structure and synthesised them starting from maleic anhydride and aniline derivatives with -COOH, -NO2, -N(C2H5)2 functional groups attached to the benzene ring. The composite films have been deposited by spin coating using a mixture of two solutions, one containing the matrix and the other the inclusion, both components of the composite system being dissolved in the same solvent. The optical transmission and photoluminescence properties of the composite films have been investigated in correlation with the morphology of the films. The scanning electron microscopy and atomic force microscopy have revealed a non-uniform morphology characterised by the development of two distinct phases. We have also investigated the generation of some optical non-linear (ONL) phenomena in these composite systems. The composite films containing as inclusions monomers characterised by the presence of one -COOH or two -NO2 substituent groups to the aromatic nucleus have shown the most intense second-harmonic generation (SHG). The second-order optical non-linear coefficients have been evaluated for these films, and the effect of the laser power on the ONL behaviour of these materials has also been emphasised.
Nonlinear optical characteristics of monolayer MoSe{sub 2}
Energy Technology Data Exchange (ETDEWEB)
Le, Chinh Tam; Ullah, Farman; Senthilkumar, Velusamy; Kim, Yong Soo [Department of Physics and Energy Harvest Storage Research Center, University of Ulsan (Korea, Republic of); Clark, Daniel J.; Jang, Joon I. [Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, NY (United States); Sim, Yumin; Seong, Maeng-Je [Department of Physics, Chung-Ang University, Seoul (Korea, Republic of); Chung, Koo-Hyun [School of Mechanical Engineering, University of Ulsan (Korea, Republic of); Park, Hyoyeol [Electronics, Communication and Semiconductor Applications Department, Ulsan College (Korea, Republic of)
2016-08-15
In this study, we utilized picosecond pulses from an Nd:YAG laser to investigate the nonlinear optical characteristics of monolayer MoSe{sub 2}. Two-step growth involving the selenization of pulsed-laser-deposited MoO{sub 3} film was employed to yield the MoSe{sub 2} monolayer on a SiO{sub 2}/Si substrate. Raman scattering, photoluminescence (PL) spectroscopy, and atomic force microscopy verified the high optical quality of the monolayer. The second-order susceptibility χ{sup (2)} was calculated to be ∝50 pm V{sup -1} at the second harmonic wavelength λ{sub SHG} ∝810 nm, which is near the optical gap of the monolayer. Interestingly, our wavelength-dependent second harmonic scan can identify the bound excitonic states including negatively charged excitons much more efficiently, compared with the PL method at room temperature. Additionally, the MoSe{sub 2} monolayer exhibits a strong laser-induced damage threshold ∝16 GW cm{sup -2} under picosecond-pulse excitation{sub .} Our findings suggest that monolayer MoSe{sub 2} can be considered as a promising candidate for high-power, thin-film-based nonlinear optical devices and applications. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Polycarbonate-Based Blends for Optical Non-linear Applications.
Stanculescu, F; Stanculescu, A
2016-12-01
This paper presents some investigations on the optical and morphological properties of the polymer (matrix):monomer (inclusion) composite materials obtained from blends of bisphenol A polycarbonate and amidic monomers. For the preparation of the composite films, we have selected monomers characterised by a maleamic acid structure and synthesised them starting from maleic anhydride and aniline derivatives with -COOH, -NO2, -N(C2H5)2 functional groups attached to the benzene ring. The composite films have been deposited by spin coating using a mixture of two solutions, one containing the matrix and the other the inclusion, both components of the composite system being dissolved in the same solvent. The optical transmission and photoluminescence properties of the composite films have been investigated in correlation with the morphology of the films. The scanning electron microscopy and atomic force microscopy have revealed a non-uniform morphology characterised by the development of two distinct phases. We have also investigated the generation of some optical non-linear (ONL) phenomena in these composite systems. The composite films containing as inclusions monomers characterised by the presence of one -COOH or two -NO2 substituent groups to the aromatic nucleus have shown the most intense second-harmonic generation (SHG). The second-order optical non-linear coefficients have been evaluated for these films, and the effect of the laser power on the ONL behaviour of these materials has also been emphasised.
Valligatla, Sreeramulu; Haldar, Krishna Kanta; Patra, Amitava; Desai, Narayana Rao
2016-10-01
The semiconductor nanocrystals are found to be promising class of third order nonlinear optical materials because of quantum confinement effects. Here, we highlight the nonlinear optical switching and optical limiting of cadmium selenide (CdSe) quantum dots (QDs) using nanosecond Z-scan measurement. The intensity dependent nonlinear absorption and nonlinear refraction of CdSe QDs were investigated by applying the Z-scan technique with 532 nm, nanosecond laser pulses. At lower intensities, the nonlinear process is dominated by saturable absorption (SA) and it is changed to reverse saturable absorption (RSA) at higher intensities. The SA behaviour is attributed to the ground state bleaching and the RSA is ascribed to free carrier absorption (FCA) of CdSe QDs. The nonlinear optical switching behaviour and reverse saturable absorption makes CdSe QDs are good candidate for all-optical device and optical limiting applications.
Progress Toward Single-Photon-Level Nonlinear Optics in Crystalline Microcavities
Kowligy, Abijith S.
Over the last two decades, the emergence of quantum information science has uncovered many practical applications in areas such as communications, imaging, and sensing where harnessing quantum features of Nature provides tremendous benefits over existing methods exploiting classical physical phenomena. In this effort, one of the frontiers of research has been to identify and utilize quantum phenomena that are not susceptible to environmental and parasitic noise processes. Quantum photonics has been at the forefront of these studies because it allows room-temperature access to its inherently quantum-mechanical features, and allows leveraging the mature telecommunication industry. Accompanying the weak environmental influence, however, are also weak optical nonlinearities. Efficient nonlinear optical interactions are indispensible for many of the existing protocols for quantum optical computation and communication, e.g. high-fidelity entangling quantum logic gates rely on large nonlinear responses at the one- or few-photon-level. While this has been addressed to a great extent by interfacing photons with single quantum emitters and cold atomic gases, scalability has remained elusive. In this work, we identify the macroscopic second-order nonlinear polarization as a robust platform to address this challenge, and utilize the recent advances in the burgeoning field of optical microcavities to enhance this nonlinear response. In particular, we show theoretically that by using the quantum Zeno effect, low-noise, single-photon-level optical nonlinearities can be realized in lithium niobate whispering-gallery-mode microcavities, and present experimental progress toward this goal. Using the measured strength of the second-order nonlinear response in lithium niobate, we modeled the nonlinear system in the strong coupling regime using the Schrodinger picture framework and theoretically demonstrated that the single-photon-level operation can be observed for cavity lifetimes in
Nonlinear interaction of two trapped-mode resonances in a bilayer "fish-scale" metamaterial
Tuz, Vladimir R; Mladyonov, Pavel L; Prosvirnin, Sergey L; Novitsky, Andrey V
2014-01-01
We report on a bistable light transmission through a bilayer "fish-scale" (meander-line) metamaterial. It is demonstrated that an all-optical switching may be achieved nearly the frequency of the high-quality-factor Fano-shaped trapped-mode resonance excitation. The nonlinear interaction of two closely spaced trapped-mode resonances in the bilayer structure composed with a Kerr-type nonlinear dielectric slab is analyzed in both frequency and time domains. It is demonstrated that these two resonances react differently on the applied intense light which leads to destination of a multistable transmission.
Third-Order Nonlinear Optic and Optical Limiting Properties of a Mn(iii) Transition Metal Complex
Karakas, Asli; Elmali, Ayhan; Yahsi, Yasemin; Kara, Hulya
N,N‧-bis(5-bromosalicylidene)propane-1,2-diamine-O,O‧,N,N‧)-manganese(III) chloride transition metal complex has been synthesized and characterized by elemental analysis and UV-vis spectroscopy. Its crystal structure has been determined using X-ray diffraction analysis. To provide an insight into the optical limiting (OL) behavior of the title compound, the third-order nonlinear optical (NLO) properties, one-photon absorption (OPA) and two-photon absorption (TPA) characterizations have been theoretically investigated by means of the time-dependent Hartree-Fock (TDHF), AM1 and configuration interaction (CI) methods, respectively. According to ab initio calculation results, the examined molecule exhibits second hyperpolarizabilities (γ) with non-zero values at the positions of TPA peaks, implying microscopic third-order optical nonlinearity. The maximum OPA wavelengths recorded by linear optical experiment and quantum mechanical computations are estimated in the UV region to be shorter than 400 nm, showing good optical transparency to the visible light. The TPA cross-sections (δ(ω)) at λ max(2) values indicate that the synthesized compound might possess OL phenomena, which are in accord with the experimental observations on the manganese complexes in the literature.
Tavassoli, Vahid
This thesis studies and mathematically models nonlinear interactions among channels of modern high bit rate (amplitude/) phase modulated optical systems. First, phase modulated analogue systems are studied and a differential receiving method is suggested with experimental validation. The main focus of the rest of the thesis is on digital advanced modulation format systems. Cross-talk due to fiber Kerr nonlinearity in two-format hybrid systems as well as 16-QAM systems is mathematically modelled and verified by simulation for different system parameters. A comparative study of differential receivers and coherent receivers is also given for hybrid systems. The model is based on mathematically proven assumptions and provides an intuitive analytical understanding of nonlinear cross-talk in such systems.
Fast Inverse Nonlinear Fourier Transform For Generating Multi-Solitons In Optical Fiber
Wahls, Sander
2015-01-01
The achievable data rates of current fiber-optic wavelength-division-multiplexing (WDM) systems are limited by nonlinear interactions between different subchannels. Recently, it was thus proposed to replace the conventional Fourier transform in WDM systems with an appropriately defined nonlinear Fourier transform (NFT). The computational complexity of NFTs is a topic of current research. In this paper, a fast inverse NFT algorithm for the important special case of multi-solitonic signals is presented. The algorithm requires only $\\mathcal{O}(D\\log^{2}D)$ floating point operations to compute $D$ samples of a multi-soliton. To the best of our knowledge, this is the first algorithm for this problem with $\\log^{2}$-linear complexity. The paper also includes a many samples analysis of the generated nonlinear Fourier spectra.
Thermal conductivities of some novel nonlinear optical materials.
Beasley, J D
1994-02-20
Results of thermal conductivity measurements are reported for several of the more recently developed nonlinear optical crystals. New or substantially revised values of thermal conductivity were obtained in six materials. Notable thermal conductivities measured were those for AgGaS(2) [0.014 W/(cm K) and 0.015 W/(cm K)], AgGaSe(2) [0.010 W/(cm K) and 0.011 W/(cm K)], beta barium borate [0.016 W/(cm K) and 0.012 W/(cm K)], and ZnGeP(2) [0.36 W/(cm K) and 0.35 W/(cm K)], with values quoted for directions respectively parallel and perpendicular to the optic axis for each material. These new data provide necessary input for the design of high-power optical frequency converters.
Linear and nonlinear magneto-optical properties of monolayer phosphorene
Nguyen, Chuong V.; Ngoc Hieu, Nguyen; Duque, C. A.; Quoc Khoa, Doan; Van Hieu, Nguyen; Van Tung, Luong; Vinh Phuc, Huynh
2017-01-01
We theoretically study the magneto-optical properties of monolayer phosphorene under a perpendicular magnetic field. We evaluate linear, third-order nonlinear, and total absorption coefficients and relative refractive index changes as functions of the photon energy and the magnetic field, and show that they are strongly influenced by the magnetic field. The magneto-optical absorption coefficients and relative refractive index changes appear in two different regimes: the microwave to THz and the visible frequency. The amplitude of intra-band transition peaks is larger than that of the inter-band transitions. The resonant peaks are blue-shifted with the magnetic field. Our results demonstrate the potential of monolayer phosphorene as a new two-dimensional material for applications in nano-electronic and optical devices as a promising alternative to graphene.
Linear addition algebra of optical nonlinearities in transparent conductive oxides
Kinsey, N; Clerici, M; Kim, J; Carnemolla, E; Shaltout, A; Kaipurath, R; Faccio, D; Shalaev, V M; Ferrera, M; Boltasseva, A
2016-01-01
The fields of nanophotonics and metamaterials have revolutionized the way we think of optical space ({\\epsilon},{\\mu}), enabling us to engineer the refractive index almost at will to confine light to the smallest of volumes as well as to manipulate optical signals with extremely small footprints and energy requirements. More recently, significant efforts have been devoted to the search for suitable materials for dynamic control, and so far, all-optical methods have primarily relied on either interband or intraband excitations. Here, we show that aluminum doped zinc oxide (AZO) supports a hybrid nonlinearity that exhibits a large and ultrafast response with controllable sign. We demonstrate that these two opposite material responses are independent and can be algebraically added together via two-color excitation, resulting in an increase in device bandwidth and unprecedented tuning capabilities. This peculiar behavior of AZO places it as a key material for next-generation ultrafast tunable nanophotonics and me...
Synthesis of Imidazole Derivatives for Their Second-order Nonlinear Optics
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
The design and the synthesis of two conjugated donor-acceptor imidazole derivatives(1, 2) were carried out for second-order nonlinear optics. The thermal properties, the transparency and second-order nonlinear optical properties of the molecules were investigated. The experimental results indicate that a good nonlinearity-transparency-thermal stability trade-off is achieved for them.
1994-09-01
Pasillas, P.; Hoover, J.; Lindsay, G.; Henry, R. J. Appi. Phys. 1990, 68 , 456. 139. Hampsch, H.; Yang, J.; Wong, G.; Torkelson, J. Macromolecules 1990, 23...New York, 1992. 295. Syms, R.; Cozens, J. Optical Guided Waves and Devices, McGraw Hill: New York, 1992. 296. Marcuse , D. Theory of Optical Dielectric
Parametric interaction and intensification of nonlinear Kelvin waves
Novotryasov, Vadim
2008-01-01
Observational evidence is presented for nonlinear interaction between mesoscale internal Kelvin waves at the tidal -- $\\omega_t$ or the inertial -- $\\omega_i$ frequency and oscillations of synoptic -- $\\Omega $ frequency of the background coastal current of Japan/East Sea. Enhanced coastal currents at the sum -- $\\omega_+ $ and dif -- $\\omega_-$ frequencies: $\\omega_\\pm =\\omega_{t,i}\\pm \\Omega$ have properties of propagating Kelvin waves suggesting permanent energy exchange from the synoptic band to the mesoscale $\\omega_\\pm $ band. The interaction may be responsible for the greater than predicted intensification, steepen and break of boundary trapped and equatorially trapped Kelvin waves, which can affect El Ni\\~{n}o. The problem on the parametric interaction of the nonlinear Kelvin wave at the frequency $\\omega $ and the low-frequency narrow-band nose with representative frequency $\\Omega\\ll\\omega $ is investigated with the theory of nonlinear week dispersion waves.
Energy Technology Data Exchange (ETDEWEB)
Zaytsev, Kirill I., E-mail: kirzay@gmail.com; Katyba, Gleb M.; Yakovlev, Egor V.; Yurchenko, Stanislav O., E-mail: st.yurchenko@mail.ru [Bauman Moscow State Technical University, 2nd Baumanskaya str. 5, Moscow 105005 (Russian Federation); Gorelik, Vladimir S. [P. N. Lebedev Physics Institute of the Russian Academy of Sciences, Leninskiy Prospekt 53, Moscow 119991 (Russian Federation)
2014-06-07
A novel approach for the enhancement of nonlinear optical effects inside globular photonic crystals (PCs) is proposed and systematically studied via numerical simulations. The enhanced optical harmonic generation is associated with two- and three-dimensional PC pumping with the wavelength corresponding to different PC band-gaps. The interactions between light and the PC are numerically simulated using the finite-difference time-domain technique for solving the Maxwell's equations. Both empty and infiltrated two-dimensional PC structures are considered. A significant enhancement of harmonic generation is predicted owing to the highly efficient PC pumping based on the structural light focusing effect inside the PC structure. It is shown that a highly efficient harmonic generation could be attained for both the empty and infiltrated two- and three-dimensional PCs. We are demonstrating the ability for two times enhancement of the parametric decay efficiency, one order enhancement of the second harmonic generation, and two order enhancement of the third harmonic generation in PC structures in comparison to the nonlinear generations in appropriate homogenous media. Obviously, the nonlinear processes should be allowed by the molecular symmetry. The criteria of the nonlinear process efficiency are specified and calculated as a function of pumping wavelength position towards the PC globule diameter. Obtained criterion curves exhibit oscillating characteristics, which indicates that the highly efficient generation corresponds to the various PC band-gap pumping. The highest efficiency of nonlinear conversions could be reached for PC pumping with femtosecond optical pulses; thus, the local peak intensity would be maximized. Possible applications of the observed phenomenon are also discussed.
Sharma, Arvind; Nagar, A. K.
2016-05-01
The origin of optical bistability and hysterectic reflectivity on account of nonlinearity at optically induced Gallium silica interface has been investigated. Assuming the wave to be incident from the gallium nano particle layer side at gallium silica interface. The coupling between incident and reflected waves has shown nonlinear effects on Snell's law and Fresnel law. Effect of these nonlinear processes optical bistability and hysterectic reflectivity theoretically has been investigated. Theoretical results obtained are consistent with the available experimental results.
Frequency-domain nonlinear optics in two-dimensionally patterned quasi-phase-matching media
Phillips, C R; Gallmann, L; Keller, U
2015-01-01
Advances in the amplification and manipulation of ultrashort laser pulses has led to revolutions in several areas. Examples include chirped pulse amplification for generating high peak-power lasers, power-scalable amplification techniques, pulse shaping via modulation of spatially-dispersed laser pulses, and efficient frequency-mixing in quasi-phase-matched nonlinear crystals to access new spectral regions. In this work, we introduce and demonstrate a new platform for nonlinear optics which has the potential to combine all of these separate functionalities (pulse amplification, frequency transfer, and pulse shaping) into a single monolithic device. Moreover, our approach simultaneously offers solutions to the performance-limiting issues in the conventionally-used techniques, and supports scaling in power and bandwidth of the laser source. The approach is based on two-dimensional patterning of quasi-phase-matching gratings combined with optical parametric interactions involving spatially dispersed laser pulses...
Vibrational spectroscopic and non-linear optical activity studies on nicotinanilide : A DFT approach
Energy Technology Data Exchange (ETDEWEB)
Premkumar, S.; Mathavan, T.; Dhas, M. Kumara; Benial, A. Milton Franklin, E-mail: miltonfranklin@yahoo.com [Department of Physics, N.M.S.S.V.N. College, Madurai-625 019, Tamil Nadu (India); Jawahar, A. [Department of Chemistry, N.M.S.S.V.N. College, Madurai-625 019, Tamil Nadu (India)
2015-06-24
The molecular structure of nicotinanilide was optimized by the DFT/B3LYP method with cc-pVTZ basis set using Gaussian 09 program. The first order hyperpolarizability of the molecule was calculated, which exhibits the higher nonlinear optical activity. The natural bond orbital analysis confirms the presence of intramolecular charge transfer and the hydrogen bonding interaction, which leads to the higher nonlinear optical activity of the molecule. The Frontier molecular orbitals analysis of the molecule shows that the delocalization of electron density occurs within the molecule. The lower energy gap indicates that the hydrogen bond formation between the charged species. The vibrational frequencies were calculated and assigned on the basis of potential energy distribution calculation using the VEDA 4.0 program and the corresponding vibrational spectra were simulated. Hence, the nicotinanilide molecule can be a good candidate for second-order NLO material.
Man, Weining; Fardad, Shima; Zhang, Ze; Prakash, Jai; Lau, Michael; Zhang, Peng; Heinrich, Matthias; Christodoulides, Demetrios N; Chen, Zhigang
2013-11-22
We demonstrate a new class of synthetic colloidal suspensions capable of exhibiting negative polarizabilities, and observe for the first time robust propagation and enhanced transmission of self-trapped light over long distances that would have been otherwise impossible in conventional suspensions with positive polarizabilities. Such light penetration through the strong scattering environment is attributed to the interplay between optical forces and self-activated transparency effects while no thermal effect is involved. By judiciously mixing colloidal particles of both negative and positive polarizabilities, we show that the resulting nonlinear response of these systems can be fine-tuned. Our experimental observations are in agreement with theoretical analysis based on a thermodynamic model that takes into account particle-particle interactions. These results may open up new opportunities in developing soft-matter systems with engineered optical nonlinearities.
Optimization of optical nonlinearities in quantum cascade lasers
Bai, Jing
Nonlinearities in quantum cascade lasers (QCL's) have wide applications in wavelength tunability and ultra-short pulse generation. In this thesis, optical nonlinearities in InGaAs/AlInAs-based mid-infrared (MIR) QCL's with quadruple resonant levels are investigated. Design optimization for the second-harmonic generation (SHG) of the device is presented. Performance characteristics associated with the third-order nonlinearities are also analyzed. The design optimization for SHG efficiency is obtained utilizing techniques from supersymmetric quantum mechanics (SUSYQM) with both material-dependent effective mass and band nonparabolicity. Current flow and power output of the structure are analyzed by self-consistently solving rate equations for the carriers and photons. Nonunity pumping efficiency from one period of the QCL to the next is taken into account by including all relevant electron-electron (e-e) and longitudinal (LO) phonon scattering mechanisms between the injector/collector and active regions. Two-photon absorption processes are analyzed for the resonant cascading triple levels designed for enhancing SHG. Both sequential and simultaneous two-photon absorption processes are included in the rate-equation model. The current output characteristics for both the original and optimized structures are analyzed and compared. Stronger resonant tunneling in the optimized structure is manifested by enhanced negative differential resistance. Current-dependent linear optical output power is derived based on the steady-state photon populations in the active region. The second-harmonic (SH) power is derived from the Maxwell equations with the phase mismatch included. Due to stronger coupling between lasing levels, the optimized structure has both higher linear and nonlinear output powers. Phase mismatch effects are significant for both structures leading to a substantial reduction of the linear-to-nonlinear conversion efficiency. The optimized structure can be fabricated
Using genetic programming to discover nonlinear variable interactions.
Westbury, Chris; Buchanan, Lori; Sanderson, Michael; Rhemtulla, Mijke; Phillips, Leah
2003-05-01
Psychology has to deal with many interacting variables. The analyses usually used to uncover such relationships have many constraints that limit their utility. We briefly discuss these and describe recent work that uses genetic programming to evolve equations to combine variables in nonlinear ways in a number of different domains. We focus on four studies of interactions from lexical access experiments and psychometric problems. In all cases, genetic programming described nonlinear combinations of items in a manner that was subsequently independently verified. We discuss the general implications of genetic programming and related computational methods for multivariate problems in psychology.
Interaction-based nonlinear quantum metrology with a cold atomic ensemble
2014-01-01
In this manuscript we present an experimental and theoretical investigation of quantum-noise-limited measurement by nonlinear interferometry, or from another perspective, quantum-noise-limited interaction-based measurement. The experimental work is performed using a polarization-based quantum interface between propagating light pulses and cold rubidium-87 atoms trapped in an optical dipole trap. We first review the theory of quantum metrology and estimation theory, and we describe theor...
Non-linear optical titanyl arsenates: Crystal growth and properties
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
Transmutation of skyrmions to half-solitons driven by the nonlinear optical spin Hall effect.
Flayac, H; Solnyshkov, D D; Shelykh, I A; Malpuech, G
2013-01-04
We show that the spin domains, generated in the linear optical spin Hall effect by the analog of spin-orbit interaction for exciton polaritons, are associated with the formation of a Skyrmion lattice. In the nonlinear regime, the spin anisotropy of the polariton-polariton interactions results in a spatial compression of the domains and in a transmutation of the Skyrmions into oblique half-solitons. This phase transition is associated with both the focusing of the spin currents and the emergence of a strongly anisotropic emission pattern.
Higher-order modulation instability in nonlinear fiber optics.
Erkintalo, Miro; Hammani, Kamal; Kibler, Bertrand; Finot, Christophe; Akhmediev, Nail; Dudley, John M; Genty, Goëry
2011-12-16
We report theoretical, numerical, and experimental studies of higher-order modulation instability in the focusing nonlinear Schrödinger equation. This higher-order instability arises from the nonlinear superposition of elementary instabilities, associated with initial single breather evolution followed by a regime of complex, yet deterministic, pulse splitting. We analytically describe the process using the Darboux transformation and compare with experiments in optical fiber. We show how a suitably low frequency modulation on a continuous wave field induces higher-order modulation instability splitting with the pulse characteristics at different phases of evolution related by a simple scaling relationship. We anticipate that similar processes are likely to be observed in many other systems including plasmas, Bose-Einstein condensates, and deep water waves.
Nonlinear optical signals and spectroscopy with quantum light
Dorfman, Konstantin E; Mukamel, Shaul
2016-01-01
Conventional nonlinear spectroscopy uses classical light to detect matter properties through the variation of its response with frequencies or time delays. Quantum light opens up new avenues for spectroscopy by utilizing parameters of the quantum state of light as novel control knobs and through the variation of photon statistics by coupling to matter. We present an intuitive diagrammatic approach for calculating ultrafast spectroscopy signals induced by quantum light, focusing on applications involving entangled photons with nonclassical bandwidth properties - known as "time-energy entanglement". Nonlinear optical signals induced by quantized light fields are expressed using time ordered multipoint correlation functions of superoperators. These are different from Glauber's g- functions for photon counting which use normally ordered products of ordinary operators. Entangled photon pairs are not subjected to the classical Fourier limitations on the joint temporal and spectral resolution. After a brief survey o...
Assessment of fibrotic liver disease with multimodal nonlinear optical microscopy
Lu, Fake; Zheng, Wei; Tai, Dean C. S.; Lin, Jian; Yu, Hanry; Huang, Zhiwei
2010-02-01
Liver fibrosis is the excessive accumulation of extracellular matrix proteins such as collagens, which may result in cirrhosis, liver failure, and portal hypertension. In this study, we apply a multimodal nonlinear optical microscopy platform developed to investigate the fibrotic liver diseases in rat models established by performing bile duct ligation (BDL) surgery. The three nonlinear microscopy imaging modalities are implemented on the same sectioned tissues of diseased model sequentially: i.e., second harmonic generation (SHG) imaging quantifies the contents of the collagens, the two-photon excitation fluorescence (TPEF) imaging reveals the morphology of hepatic cells, while coherent anti-Stokes Raman scattering (CARS) imaging maps the distributions of fats or lipids quantitatively across the tissue. Our imaging results show that during the development of liver fibrosis (collagens) in BDL model, fatty liver disease also occurs. The aggregated concentrations of collagen and fat constituents in liver fibrosis model show a certain correlationship between each other.
Nonlinear optical absorption of photosynthetic pigment molecules in leaves.
Ye, Zi-Piao
2012-04-01
A mathematical formulation of the relationship between optical absorption coefficient of photosynthetic pigment molecules and light intensity was developed. It showed that physical parameters of photosynthetic pigment molecule (i.e., light absorption cross-section of photosynthetic pigment molecule, its average lifetime in the excited state, total photosynthetic pigment molecules, the statistical weight, or degeneracy of energy level of photosynthetic pigment molecules in the ground state and in the excited state) influenced on both the light absorption coefficient and effective light absorption cross-section of photosynthetic pigment molecules. Moreover, it also showed that both the light absorption coefficient and effective light absorption cross-section of photosynthetic pigment molecules were not constant, they decreased nonlinearly with light intensity increasing. The occupation numbers of photosynthetic pigment molecules in the excited states increased nonlinearly with light intensity increasing.
Linear and nonlinear optical response of spherical anisotropic semiconductor microcrystallites
Ramaniah, Lavanya M.; Nair, Selvakumar V.; Rustagi, Kailash C.
1989-12-01
We present a phenomenological theory of the linear and nonlinear optical properties associated with the Fröhlich resonances of an optically anisotropic, spherical semiconductor crystallite. Using the Maxwell-Garnett approach, we calculate the effective dielectric function of a composite medium containing such crystallites. To study the effect of anisotropy, we take CdS and CdSe quantum dots as examples for the inclusions, and use a two-resonance model for the dielectric function. Even for randomly oriented inclusions, the Fröhlich resonances split as a result of anisotropic local-field corrections. At higher laser intensities, absorption saturation leads to bistability or tristability in the optical response of individual crystallites, while the response of the composite medium with randomly oriented inclusions shows multistability, with many intermediate branches. The nonlinear response of such a composite medium also exhibits a new kind of orientation-induced broadening of resonances. We also find that tristability is possible in another kind of inhomogeneous material, viz., a composite medium containing two types of isotropic spherical crystallites.
Automated control of optical polarization for nonlinear microscopy
Brideau, Craig; Stys, Peter K.
2012-03-01
Laser-scanning non-linear optical techniques such as multi-photon fluorescence excitation microscopy (MPM), Second/ Third Harmonic Generation (SHG/THG), and Coherent Anti-Stokes Raman Scattering (CARS) are being utilized in research laboratories worldwide. The efficiencies of these non-linear effects are dependent on the polarization state of the excitation light relative to the orientation of the sample being imaged. In highly ordered anisotropic biological samples this effect can become pronounced and the excitation polarization can have a dramatic impact on imaging experiments. Therefore, controlling the polarization state of the exciting light is important; however this is challenging when the excitation light passes through a complex optical system. In a typical laser-scanning microscope, components such as the dichroic filters, lenses, and even mirrors can alter the polarization state of a laser beam before it reaches the sample. We present an opto-mechanical solution to compensate for the polarization effects of an optical path, and to precisely program the polarization state of the exciting laser light. The device and accompanying procedures allow the delivery of precise laser polarization states at constant average power levels to a sample during an imaging experiment.
Maximum Likelihood Sequence Detection Receivers for Nonlinear Optical Channels
Directory of Open Access Journals (Sweden)
Gabriel N. Maggio
2015-01-01
Full Text Available The space-time whitened matched filter (ST-WMF maximum likelihood sequence detection (MLSD architecture has been recently proposed (Maggio et al., 2014. Its objective is reducing implementation complexity in transmissions over nonlinear dispersive channels. The ST-WMF-MLSD receiver (i drastically reduces the number of states of the Viterbi decoder (VD and (ii offers a smooth trade-off between performance and complexity. In this work the ST-WMF-MLSD receiver is investigated in detail. We show that the space compression of the nonlinear channel is an instrumental property of the ST-WMF-MLSD which results in a major reduction of the implementation complexity in intensity modulation and direct detection (IM/DD fiber optic systems. Moreover, we assess the performance of ST-WMF-MLSD in IM/DD optical systems with chromatic dispersion (CD and polarization mode dispersion (PMD. Numerical results for a 10 Gb/s, 700 km, and IM/DD fiber-optic link with 50 ps differential group delay (DGD show that the number of states of the VD in ST-WMF-MLSD can be reduced ~4 times compared to an oversampled MLSD. Finally, we analyze the impact of the imperfect channel estimation on the performance of the ST-WMF-MLSD. Our results show that the performance degradation caused by channel estimation inaccuracies is low and similar to that achieved by existing MLSD schemes (~0.2 dB.
Optical nonlinearity enhancement with graphene-decorated silicon waveguides
Ishizawa, Atsushi; Kou, Rai; Goto, Takahiro; Tsuchizawa, Tai; Matsuda, Nobuyuki; Hitachi, Kenichi; Nishikawa, Tadashi; Yamada, Koji; Sogawa, Tetsuomi; Gotoh, Hideki
2017-04-01
Broadband on-chip optical frequency combs (OFCs) are important for expanding the functionality of photonic integrated circuits. Here, we demonstrate a huge local optical nonlinearity enhancement using graphene. A waveguide is decorated with graphene by precisely manipulating graphene’s area and position. Our approach simultaneously achieves both an extremely efficient supercontinuum and ultra-short pulse generation. With our graphene-decorated silicon waveguide (G-SWG), we have achieved enhanced spectral broadening of femtosecond pump pulses, along with an eightfold increase in the output optical intensity at a wavelength approximately 200 nm shorter than that of the pump pulses. We also found that this huge nonlinearity works as a compressor that effectively compresses pulse width from 80 to 15.7 fs. Our results clearly show the potential for our G-SWG to greatly boost the speed and capacity of future communications with lower power consumption, and our method will further decrease the required pump laser power because it can be applied to decorate various kinds of waveguides with various two-dimensional materials.
Z-scan: A simple technique for determination of third-order optical nonlinearity
Energy Technology Data Exchange (ETDEWEB)
Singh, Vijender, E-mail: chahal-gju@rediffmail.com [Department of Applied Science, N.C. College of Engineering, Israna, Panipat-132107, Haryana (India); Aghamkar, Praveen, E-mail: p-aghamkar@yahoo.co.in [Department of Physics, Chaudhary Devi Lal University, Sirsa-125055, Haryana (India)
2015-08-28
Z-scan is a simple experimental technique to measure intensity dependent nonlinear susceptibilities of third-order nonlinear optical materials. This technique is used to measure the sign and magnitude of both real and imaginary part of the third order nonlinear susceptibility (χ{sup (3)}) of nonlinear optical materials. In this paper, we investigate third-order nonlinear optical properties of Ag-polymer composite film by using single beam z-scan technique with Q-switched, frequency doubled Nd: YAG laser (λ=532 nm) at 5 ns pulse. The values of nonlinear absorption coefficient (β), nonlinear refractive index (n{sub 2}) and third-order nonlinear optical susceptibility (χ{sup (3)}) of permethylazine were found to be 9.64 × 10{sup −7} cm/W, 8.55 × 10{sup −12} cm{sup 2}/W and 5.48 × 10{sup −10} esu, respectively.
Institute of Scientific and Technical Information of China (English)
CAO; Wenhua; LIU; Songhao
2004-01-01
A novel scheme to compress optical pulses is proposed and demonstrated numerically, which is based on a nonlinear optical loop mirror constructed from dispersion decreasing fiber (DDF). We show that, in contrast to the conventional soliton-effect pulse compression in which compressed pulses are always accompanied by pedestals and frequency chirps owning to nonlinear effects, the proposed scheme can completely suppress pulse pedestals and frequency chirps. Unlike the adiabatic compression technique in which DDF length must increase exponentially with input pulsewidth, the proposed scheme does not require adiabatic condition and therefore can be used to compress long pulses by using reasonable fiber lengths. For input pulses with peak powers higher than a threshold value, the compressed pulses can propagate like fundamental solitons. Furthermore, the scheme is fairly insensitive to small variations in the loop length and is more robust to higher-order nonlinear effects and initial frequency chirps than the adiabatic compression technique.
Min, Changjun; Wang, Pei; Chen, Chunchong; Deng, Yan; Lu, Yonghua; Ming, Hai; Ning, Tingyin; Zhou, Yueliang; Yang, Guozhen
2008-04-15
All-optical switching based on a subwavelength metallic grating structure containing nonlinear optical materials has been proposed and numerically investigated. Metal-dielectric composite material is used in the switching for its larger third-order nonlinear susceptibility (approximately 10(-7)esu) and ultrafast response properties. The calculated dependence of the signal light intensity on the pump light intensity shows a bistable behavior, which results in a significant switch effect. It rests on a surface plasmon's enhanced intensity-dependent change of the effective dielectric constant of Kerr nonlinear media, corresponding to a transition of the far-field transmission from a low- to high-transmission state. The study of this switching structure shows great advantages of smaller size, lower requirement of pump light intensity, and shorter switching time at approximately the picosecond level.
Cascaded Optical Buffer Based on Nonlinear Polarization Rotation in Semiconductor Optical Amplifiers
Institute of Scientific and Technical Information of China (English)
CHENG Mu; WU Chong-Qing; LIU Hua
2008-01-01
A cascaded buffer based on nonlinear polarization rotation in semiconductor optical amplifiers is proposed, which is suitable for fast reconfiguration of buffering time at picoseconds. With the proposed buffer, sixty different buffer times are demonstrated at 2.5 Gb/s.
Kinetic equation for nonlinear resonant wave-particle interaction
Artemyev, A. V.; Neishtadt, A. I.; Vasiliev, A. A.; Mourenas, D.
2016-09-01
We investigate the nonlinear resonant wave-particle interactions including the effects of particle (phase) trapping, detrapping, and scattering by high-amplitude coherent waves. After deriving the relationship between probability of trapping and velocity of particle drift induced by nonlinear scattering (phase bunching), we substitute this relation and other characteristic equations of wave-particle interaction into a kinetic equation for the particle distribution function. The final equation has the form of a Fokker-Planck equation with peculiar advection and collision terms. This equation fully describes the evolution of particle momentum distribution due to particle diffusion, nonlinear drift, and fast transport in phase-space via trapping. Solutions of the obtained kinetic equation are compared with results of test particle simulations.
Interactions between nonlinear spur gear dynamics and surface wear
Ding, Huali; Kahraman, Ahmet
2007-11-01
In this study, two different dynamic models, a finite elements-based deformable-body model and a simplified discrete model, and a surface wear model are combined to study the interaction between gear surface wear and gear dynamic response. The proposed dynamic gear wear model includes the influence of worn surface profiles on dynamic tooth forces and transmission error as well as the influence of dynamic tooth forces on wear profiles. This paper first introduces the nonlinear dynamic models that include gear backlash and time-varying gear mesh stiffness, and a wear model separately. It presents a comparison to experiments for validation of the dynamic models. The dynamic models are combined with the wear model to study the interaction of surface wear and dynamic behavior in both linear and nonlinear response regimes. At the end, several sets of simulation results are used to demonstrate the two-way relationship between nonlinear gear dynamics and surface wear.
Nonlinear lepton-photon interactions in external background fields
Energy Technology Data Exchange (ETDEWEB)
Akal, Ibrahim [DESY, Hamburg (Germany). Theory Group; Moortgat-Pick, Gudrid [DESY, Hamburg (Germany). Theory Group; Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik
2016-02-09
Nonlinear phenomena of lepton-photon interactions in external backgrounds with a generalised periodic plane-wave geometry are studied. We discuss nonlinear Compton scattering in head-on lepton-photon collisions extended properly to beyond the soft-photon regime. In addition, our results are applied to stimulated lepton-antilepton pair production in photon collisions with unrestricted energies. Derivations are considered semi-classically based on unperturbed fermionic Volkov representations encoding the full interaction with the background field. Closed expressions for total probabilities considering S-matrix elements have been derived. The general formula is applied to Compton scattering by an electron propagating in an external laser-like background. We obtain additive contributions in the extended unconstrained result which turns out to be stringently required in the highly nonlinear regime. A detailed comparison of contributing harmonics is discussed for various field parameters.
Theory of plasmonic effects in nonlinear optics: The case of graphene
Rostami, Habib; Katsnelson, Mikhail I.; Polini, Marco
2017-01-01
We develop a microscopic large-N theory of electron-electron interaction corrections to multilegged Feynman diagrams describing second- and third-order non-linear-response functions. Our theory, which reduces to the well-known random-phase approximation in the linear-response limit, is completely general and is useful to understand all second- and third-order nonlinear effects, including harmonic generation, wave mixing, and photon drag. We apply our theoretical framework to the case of graphene, by carrying out microscopic calculations of the second- and third-order non-linear-response functions of an interacting two-dimensional (2D) gas of massless Dirac fermions. We compare our results with recent measurements, where all-optical launching of graphene plasmons has been achieved by virtue of the finiteness of the quasihomogeneous second-order nonlinear response of this inversion-symmetric 2D material.
Optical Multi-hysteresises and "Rogue Waves" in Nonlinear Plasma
Kaplan, A E
2010-01-01
An overdense plasma layer irradiated by an intense light can exhibit dramatic nonlinear-optical effects due to a relativistic mass-effect of free electrons: highly-multiple hysteresises of reflection and transition, and emergence of gigantic "rogue waves". Those are trapped quasi-soliton field spikes inside the layer, sustained by an incident radiation with a tiny fraction of their peak intensity once they have been excited by orders of magnitude larger pumping. The phenomenon persists even in the layers with "soft" boundaries, as well as in a semi-infinite plasma with low absorption.
Molecular design of porphyrin-based nonlinear optical materials.
Keinan, Shahar; Therien, Michael J; Beratan, David N; Yang, Weitao
2008-11-27
Nonlinear optical chromophores containing (porphyrinato)Zn(II), proquinoid, and (terpyridyl)metal(II) building blocks were optimized in a library containing approximately 10(6) structures using the linear combination of atomic potentials (LCAP) methodology. We report here the library design and molecular property optimizations. Two basic structural types of large beta(0) chromophores were examined: linear and T-shaped motifs. These T-shaped geometries suggest a promising NLO chromophoric architecture for experimental investigation and further support the value of performing LCAP searches in large chemical spaces.
Fabrication of nonlinear plastic optical fiber (POF) and application
Kim, Eung Soo; Kinoshita, Takeshi; Yu, Yun Sik; Jeong, Myung Yung
2007-04-01
We have developed a fabrication technique for plastic optical fiber (POF) using nonlinear organic materials. The fabrication technique is the direct core solution injection into the hole of cladding preform formed by polymerization of cladding solution. The cladding solution was made of MMA, BBP, and BPO. The preform of fiber was drawn into fiber following polymerization of core solution in cladding preform. We used DR1 to control the refractive index of fiber and investigated the sensor characteristics. The sensitivity of fabricated fiber is about 0.11 W/°C in the temperature range from 20 °C to 100 °C.
Field-enhanced nonlinear optical properties of organic nanofibers
DEFF Research Database (Denmark)
Kostiučenko, Oksana; Fiutowski, Jacek; Brewer, Jonathan R.;
Second harmonic generation in nonlinearly optically active organic nanofibers, generated via self-assembled surface growth from nonsymmetrically functionalized para-quarterphenylene (CNHP4) molecules, has been investigated. After the growth on mica templates, nanofibers have been transferred onto...... lithographically defined regular arrays of metal and dielectric nanostructures. Such hybrid systems were employed to correlate the second harmonic response to both morphology of the fibers i.e. local field enhancement due to local changes in the fiber’s morphology and field enhancement effects appearing...
Field-enhanced nonlinear optical properties of organic nanofibers
DEFF Research Database (Denmark)
Kostiučenko, Oksana; Fiutowski, Jacek; Brewer, Jonathan R.;
2014-01-01
Second harmonic generation in nonlinearly optically active organic nanofibers, generated via self-assembled surface growth from nonsymmetrically functionalized para-quarterphenylene (CNHP4) molecules, has been investigated. After the growth on mica templates, nanofibers have been transferred onto...... lithographically defined regular arrays of metal and dielectric nanostructures. Such hybrid systems were employed to correlate the second harmonic response to both morphology of the fibers i.e. local field enhancement due to local changes in the fiber’s morphology and field enhancement effects appearing...
Integrable nonlinear parity-time symmetric optical oscillator
Hassan, Absar U; Miri, Mohammad-Ali; Khajavikhan, Mercedeh; Christodoulides, Demetrios N
2016-01-01
The nonlinear dynamics of a balanced parity-time symmetric optical microring arrangement are analytically investigated. By considering gain and loss saturation effects, the pertinent conservation laws are explicitly obtained in the Stokes domain-thus establishing integrability. Our analysis indicates the existence of two regimes of oscillatory dynamics and frequency locking, both of which are analogous to those expected in linear parity-time symmetric systems. Unlike other saturable parity time symmetric systems considered before, the model studied in this work first operates in the symmetric regime and then enters the broken parity-time phase.
Directory of Open Access Journals (Sweden)
Lianwei Chen
2014-01-01
Full Text Available Silicon nanoparticles at different doping concentrations are investigated for tuning their optical nonlinear performance. The silicon nanoparticles are synthesized from doped silicon wafers by pulsed laser ablation. Their dispersions in water are studied for both nonlinear absorption and nonlinear refraction properties. It is found that the optical nonlinear performance can be modified by the doping concentration. Nanoparticles at a higher doping concentration exhibit better saturable absorption performance for femtosecond laser pulse, which is ascribed to the free carrier absorption mechanism.
Multilayer Au/TiO2 Composite Films with Ultrafast Third-Order Nonlinear Optical Properties
Institute of Scientific and Technical Information of China (English)
LONG Hua; YANG Guang; CHEN Ai-Ping; LI Yu-Hua; LU Pei-Xiang
2008-01-01
We report on the ultrafast third-order optical nonlinearity in multilayer Au/TiO2 composite films fabricated on quartz substrates by pulsed laser deposition technique. The linear optical properties of the films are determined and optical absorption peaks due to surface plasmon resonance of Au particles are observed at about 59Onm.The third-order optical nonlinearities of the films are investigated by z-scan method using a femtosecond laser(50 fs) at the wavelength of 800 nm. The sample showed fast nonlinear optical responses with nonlinear absorption coefficient and nonlinear refractive index being -3.66×10-10 m/W and -2.95×10-17 m2/W, respectively. The results also show that the nonlinear optical effects increase with the increasing Au concentration in the composite films.
640 Gbit/s optical time-division add-drop multiplexing in a non-linear optical loop mirror
DEFF Research Database (Denmark)
Mulvad, Hans Christian Hansen; Galili, Michael; Oxenløwe, Leif Katsuo
2009-01-01
Error-free 640 Gbit/s all-optical time-division add-drop multiplexing is demonstrated using a non-linear optical loop mirror. Both the add- and drop operations are achieved simultaneously by switching.......Error-free 640 Gbit/s all-optical time-division add-drop multiplexing is demonstrated using a non-linear optical loop mirror. Both the add- and drop operations are achieved simultaneously by switching....
Institute of Scientific and Technical Information of China (English)
M. Singh; P. Aghamkar; S. Duhan
2008-01-01
Using electromagnetic treatment, an expression of effective nonlinear optical susceptibility Xe[= Xe(2) + Xe(3) E] is obtained for Ⅲ-Ⅴ semiconducting crystals in an applied transverse dc magnetic field under off-resonant transition regime. The origin of nonlinear interaction lies in nonlinear polarization arising from the crystal properties such as piezoelectricity and electrostriction. Numerical estimates have been made by a representative n-InSb crystal at 77K duly irradiated by a pulsed lO.6-μm CO2 laser under off-resonant transition regime. Efforts are dedicated to optimizing doping level and externally applied dc magnetic field to achieve maximum Xe(2) and Xe(3). The results are found to be in good agreement with the available literature. The analysis shows that Xe(2) and Xe(3)can be significantly enhanced in doped Ⅲ-Ⅴ semiconductors by the proper selection of doping concentration and dc magnetic field, which confirms its potential as a candidate material for the fabrication of nonlinear optical devices.
Emerging Low-Dimensional Materials for Nonlinear Optics and Ultrafast Photonics.
Liu, Xiaofeng; Guo, Qiangbing; Qiu, Jianrong
2017-02-22
Low-dimensional (LD) materials demonstrate intriguing optical properties, which lead to applications in diverse fields, such as photonics, biomedicine and energy. Due to modulation of electronic structure by the reduced structural dimensionality, LD versions of metal, semiconductor and topological insulators (TIs) at the same time bear distinct nonlinear optical (NLO) properties as compared with their bulk counterparts. Their interaction with short pulse laser excitation exhibits a strong nonlinear character manifested by NLO absorption, giving rise to optical limiting or saturated absorption associated with excited state absorption and Pauli blocking in different materials. In particular, the saturable absorption of these emerging LD materials including two-dimensional semiconductors as well as colloidal TI nanoparticles has recently been utilized for Q-switching and mode-locking ultra-short pulse generation across the visible, near infrared and middle infrared wavelength regions. Beside the large operation bandwidth, these ultrafast photonics applications are especially benefit from the high recovery rate as well as the facile processibility of these LD materials. The prominent NLO response of these LD materials have also provided new avenues for the development of novel NLO and photonics devices for all-optical control as well as optical circuits beyond ultrafast lasers.
An Agent Interaction Based Method for Nonlinear Process Plan Scheduling
Institute of Scientific and Technical Information of China (English)
GAO Qinglu; WU Bo; GUO Guang
2006-01-01
This article puts forward a scheduling method for nonlinear process plan shop floor. Task allocation and load balance are realized by bidding mechanism. Though the agent interaction process, the execution of tasks is determined and the coherence of manufacturing decision is verified. The employment of heuristic index can help to optimize the system performance.
Non-Linear Interactive Stories in Computer Games
DEFF Research Database (Denmark)
Bangsø, Olav; Jensen, Ole Guttorm; Kocka, Tomas
2003-01-01
The paper introduces non-linear interactive stories (NOLIST) as a means to generate varied and interesting stories for computer games automatically. We give a compact representation of a NOLIST based on the specification of atomic stories, and show how to build an object-oriented Bayesian network...
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.
Ultrafast Third-Order Nonlinear Optical Spectroscopy of Chlorinated Hydrocarbons
Energy Technology Data Exchange (ETDEWEB)
Napoleon Thantu; Robert S. Schley
2003-09-01
Time-resolved Raman induced Kerr effect spectroscopy in the optical heterodyne detection configuration has been employed to investigate intermolecular, intramolecular, and reorientational dynamics in neat trichloroethylene (TCE). The reorientation time constant is directly measured from the time-resolved data, while Fourier transformation of the time-resolved data yields the intermolecular and intramolecular vibrational spectrum. Use of ultrashort, femtosecond pulses enables excitation of depolarized Raman-active transitions between 1 and 500 cm-1. The intramolecular vibrations have been identified using a previous assignment. The limitations imposed by the laser and detector noise, and other nonlinear optical processes that are manifest at high pulse intensities, on the use of this time-domain technique for performing chemical species detection are discussed using carbon tetrachloride as an example.
Figures of merit of nonlinear optical chromophores in photorefractive polymers
Barzoukas, Marguerite; Blanchard-Desce, Mireille H.; Wortmann, Ruediger W.
1999-05-01
A pre-requisite to obtain polymers with a large photorefractive response is to design non-linear optical chromophores with a large figure of merit. This figure depends on the glass transition temperature of the material. We present a theoretical investigation that shows which are the important molecular parameters that control the magnitude of the figure of merit either in a low-Tg or in a high-Tg polymer. Derivation of the figures of merit for various push-pull molecules show a molecular engineering strategy can be successfully implemented to yield very large figures of merit. This approach is supported by an experimental investigation based on electro-optical absorption measurements.
Low power continuous wave laser induced optical nonlinearities in saffron ( Crocus Sativus L.)
Nasibov, H.; Mamedbeili, I.
2010-12-01
We report on the low power CW laser induced nonlinear optical responses of Saffron (stigmata of Crocus Savitus L.) ethanol and methanol extracts. The optical nonlinearities were investigated by performing Z-scan measurements at 470 and 535 nm wavelengths. At both wavelengths the material has a strong nonlinear refraction, mainly of thermal origin. However, only at 470 nm wavelength the material exhibit pronounced saturable nonlinear absorption. Long-term (70 days) stability measurements indicated that the nonlinearities in the Saffron extracts are due to their nonvolatile components. This study shows that there is great potential for Saffron extracts to be used in nonlinear photonic applications.
Nonlinear optical response of some Graphene oxide and Graphene fluoride derivatives
Liaros, Nikolaos; Orfanos, Ioannis; Papadakis, Ioannis; Couris, Stelios
2016-12-01
The nonlinear optical properties of two graphene derivatives, graphene oxide and graphene fluoride, are investigated by means of the Z-scan technique employing 35 ps and 4 ns, visible (532 nm) laser excitation. Both derivatives were found to exhibit significant third-order nonlinear optical response at both excitation regimes, with the nonlinear absorption being relatively stronger and concealing the presence of nonlinear refraction under ns excitation, while ps excitation reveals the presence of both nonlinear absorption and refraction. Both nonlinear properties are of great interest for several photonics, opto-fluidics, opto-electronics and nanotechnology applications.
Indian Academy of Sciences (India)
Hussain A Badran; Alaa Y Al-Ahmad; Qusay M Ali Hassan; Chassib A Emshary
2016-01-01
The optical properties of Violet 1-doped polyvinyl alcohol (PVA) have been investigated using Wemble and Didomenico (WD) method. The optical constants such as refractive index , the dispersion energy , the oscillation energy 0, the lattice dielectric constant ∞, light frequency dielectric constant 0 and the ratio of carrier concentration to the effective mass /* have been determined using reflection spectra in the wavelength range 300–900 nm. The singlebeam Z-scan technique was used to determine the nonlinear optical properties of Violet 1:polyvinylalcohol (PVA) thin film. The experiments were performed using continuous wave (cw) laser with a wavelength of 635 nm. The calculated nonlinear refractive index of the film, $n_{2} = -2.79 \\times 10^{-7}$ cm2/Wand nonlinear absorption coefficient, $\\beta = 6.31\\times10^{−3}$ cm/W. Optical limiting characteristics of the dye-doped polymer film was studied. The result reveals that Violet 1 can be a promising material for optical limiting applications.
MoS2 /Carbon Nanotube Core-Shell Nanocomposites for Enhanced Nonlinear Optical Performance.
Zhang, Xiaoyan; Selkirk, Andrew; Zhang, Saifeng; Huang, Jiawei; Li, Yuanxin; Xie, Yafeng; Dong, Ningning; Cui, Yun; Zhang, Long; Blau, Werner J; Wang, Jun
2017-03-08
Nanocomposites of layered MoS2 and multi-walled carbon nanotubes (CNTs) with core-shell structure were prepared by a simple solvothermal method. The formation of MoS2 nanosheets on the surface of coaxial CNTs has been confirmed by scanning electron microscopy, transmission electron microscopy, absorption spectrum, Raman spectroscopy, and X-ray photoelectron spectroscopy. Enhanced third-order nonlinear optical performances were observed for both femtosecond and nanosecond laser pulses over a broad wavelength range from the visible to the near infrared, compared to those of MoS2 and CNTs alone. The enhancement can be ascribed to the strong coupling effect and the photoinduced charge transfer between MoS2 and CNTs. This work affords an efficient way to fabricate novel CNTs based nanocomposites for enhanced nonlinear light-matter interaction. The versatile nonlinear properties imply a huge potential of the nanocomposites in the development of nanophotonic devices, such as mode-lockers, optical limiters, or optical switches.
Sifain, Andrew E; Tadesse, Loza F; Bjorgaard, Josiah A; Chavez, David E; Prezhdo, Oleg V; Scharff, R Jason; Tretiak, Sergei
2017-03-21
Conjugated energetic molecules (CEMs) are a class of explosives with high nitrogen content that posses both enhanced safety and energetic performance properties and are ideal for direct optical initiation. As isolated molecules, they absorb within the range of conventional lasers. Crystalline CEMs are used in practice, however, and their properties can differ due to intermolecular interaction. Herein, time-dependent density functional theory was used to investigate one-photon absorption (OPA) and two-photon absorption (TPA) of monomers and dimers obtained from experimentally determined crystal structures of CEMs. OPA scales linearly with the number of chromophore units, while TPA scales nonlinearly, where a more than 3-fold enhancement in peak intensity, per chromophore unit, is calculated. Cooperative enhancement depends on electronic delocalization spanning both chromophore units. An increase in sensitivity to nonlinear laser initiation makes these materials suitable for practical use. This is the first study predicting a cooperative enhancement of the nonlinear optical response in energetic materials composed of relatively small molecules. The proposed model quantum chemistry is validated by comparison to crystal structure geometries and the optical absorption of these materials dissolved in solution.
Nonlinear interaction of waves in boundary-layer flows
Nayfeh, A. H.; Bozatli, A. N.
1979-01-01
First-order nonlinear interactions of Tollmien-Schlichting waves of different frequencies and initial amplitudes in boundary-layer flows are analyzed by using the method of multiple scales. For the case of two waves, a strong nonlinear interaction exists if one of the frequencies w2 is twice the other frequency w1. Numerical results for flow past a flat plate show that this interaction mechanism is strongly destabilizing even in regions where either the fundamental or its harmonic is damped in the absence of the interaction. For the case of three waves, a strong nonlinear interaction exists when w3 = w2- w1. This combination resonance causes the amplitude of the wave with the difference frequency w3 to multiply many times in magnitude in a short distance even if it is damped in the absence of the interaction. The initial amplitudes play a dominant role in determining the changes in the amplitudes of the waves in both of these mechanisms.
Characterizing the Statistics of a Bunch of Optical Pulses Using a Nonlinear Optical Loop Mirror
Directory of Open Access Journals (Sweden)
Olivier Pottiez
2015-01-01
Full Text Available We propose in this work a technique for determining the amplitude distribution of a wave packet containing a large number of short optical pulses with different amplitudes. The technique takes advantage of the fast response of the optical Kerr effect in a fiber nonlinear optical loop mirror (NOLM. Under some assumptions, the statistics of the pulses can be determined from the energy transfer characteristic of the packet through the NOLM, which can be measured with a low-frequency detection setup. The statistical distribution is retrieved numerically by approximating the solution of a system of nonlinear algebraic equations using the least squares method. The technique is demonstrated numerically in the case of a packet of solitons.
Nonlinear optical spectroscopy of isotropic and anisotropic metallic nanocomposites
Energy Technology Data Exchange (ETDEWEB)
Fernandez-Hernandez, R C; Gleason-Villagran, R; Cheang-Wong, J C; Crespo-Sosa, A; Rodriguez-Fernandez, L; Lopez-Suarez, A; Oliver, A; Reyes-Esqueda, J A [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico, D. F. 04510 (Mexico); Torres-Torres, C [Seccion de Estudios de Posgrado e Investigacion, ESIME-Zacatenco, Instituto Politecnico Nacional, Mexico, D. F. 07338 (Mexico); Rangel-Rojo, R, E-mail: reyes@fisica.unam.mx [CICESE/Depto. de Optica, A.P. 360, Ensenada, B. C. 22860 (Mexico)
2011-01-01
In this work, we studied the nonlinear absorption and refraction of isotropic and anisotropic metallic nanocomposites, which consist of Au and Ag nanoparticles (NPs) embedded in matrices of SiO{sub 2}. We performed this study at different wavelengths using the Z-scan technique in the picosecond regime. The wavelengths were selected accordingly to the absorption spectra of the nanocomposites, choosing wavelengths into the inter- and intra-band transitions regions, including the surface plasmon (SP) resonance, as well as in the transparent region. For the anisotropic nanocomposites, the polarization and the incident angle were varied in order to evaluate the different components of the third order susceptibility tensor, {chi}{sup (3)}. We observed dramatic changes of sign for both, nonlinear refraction and absorption, when passing from Au to Ag and/or varying the wave length. The results accentuate the importance of the hot-electrons contribution to the nonlinear optical response at this temporal regime, when compared to inter-band and intra-band transitions contributions.
Pérez-Moreno, Javier; Clays, Koen
The generalized Thomas-Kuhn sum rules are used to characterize the nonlinear optical response of organic chromophores in terms of fundamental parameters that can be measured experimentally. The nonlinear optical performance of organic molecules is evaluated from the combination of hyper-Rayleigh scattering measurements and the analysis in terms of the fundamental limits. Different strategies for the enhancement of nonlinear optical behavior at the molecular and supramolecular level are evaluated and new paradigms for the design of more efficient nonlinear optical molecules are proposed and investigated.
Investigation of local and nonlocal nonlinear optical refraction effect in IZO thin films
Htwe, Zin Maung; Zhang, Yun-Dong; Yao, Cheng-Bao; Li, Hui; Yuan, Ping
2016-10-01
We report the local and nonlocal nonlinear optical refraction properties of indium doped zinc oxide (IZO) thin films using closed aperture Z-scan technique. The Z-scan results show the films have positive nonlinear optical refraction properties. The nonlocal parameter m of samples is increased with indium. In both of local and nonlocal studies, the nonlinear optical refractions of thin films were increased with In contents and laser energy. This relation reveals the role of In composition in IZO affects on the nonlinear optical responses of the films. These results make the IZO thin films as the promising application in optoelectronics devices.
Analysis of linear and nonlinear genotype × environment interaction
Directory of Open Access Journals (Sweden)
Rong-Cai eYang
2014-07-01
Full Text Available The usual analysis of genotype × environment interaction (GxE is based on the linear regression of genotypic performance on environmental changes (e.g., classic stability analysis. This linear model may often lead to lumping together of the nonlinear responses to the whole range of environmental changes from suboptimal and superoptimal conditions, thereby lowering the power of detecting GxE variation. On the other hand, the GxE is present when the magnitude of the genetic effect differs across the range of environmental conditions regardless of whether the response to environmental changes is linear or nonlinear. The objectives of this study are: (i explore the use of four commonly used nonlinear functions (logistic, parabola, normal and Cauchy functions for modeling nonlinear genotypic responses to environmental changes and (ii to investigate the difference in the magnitude of estimated genetic effects under different environmental conditions. The use of nonlinear functions was illustrated through the analysis of one data set taken from barley cultivar trials in Alberta, Canada (Data A and the examination of change in effect sizes is through the analysis another data set taken from the North America Barley Genome Mapping Project (Data B. The analysis of Data A showed that the Cauchy function captured an average of >40% of total GxE variation whereas the logistic function captured less GxE variation than the linear function. The analysis of Data B showed that genotypic responses were largely linear and that strong QTL × environment interaction existed as the positions, sizes and directions of QTL detected differed in poor vs. good environments. We conclude that (i the nonlinear functions should be considered when analyzing multi-environmental trials with a wide range of environmental variation and (ii QTL × environment interaction can arise from the difference in effect sizes across environments.
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.
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.
Thioborates: potential nonlinear optical materials with rich structural chemistry.
Lian, Yu-Kun; Wu, Li-Ming; Chen, Ling
2017-03-27
Nonlinear optical (NLO) crystal materials with good performance are urgently needed. Various compounds have been explored to date. Metal chalcogenides and borates are common sources of potential NLO materials with desirable properties, particularly in the IR and UV regions, respectively. However, these two types of crystals have their specific drawbacks. Thioborates, as an emerging system, have unique advantages by combining the merits of borates and sulfides, i.e., the high laser damage thresholds and rich structural diversity of borates with large optical nonlinearity and the favorable transparency range of sulfides. However, only a limited number of thioborates are known. This paper summarizes the known thioborates according to structural motifs that range from zero-dimension to three-dimension, most of which are formed by sharing corners of the basic building units (BS3)(3-) and (BS4)(5-). Although nearly one-third of the known thioborates are noncentrosymmetric, most of their properties, especially their NLO behaviors, are unexplored. Further attempts and additional investigations are required with respect to design syntheses, property improvements and micro-mechanism studies.
Organic non-linear optics and opto-electronics
Maldonado, J. L.; Ramos-Ortíz, G.; Rodríguez, M.; Meneses-Nava, M. A.; Barbosa-García, O.; Santillán, R.; Farfán, N.
2010-12-01
π-conjugated organic molecules and polymers are of great importance in physics, chemistry, material science and engineering. It is expected that, in the near future, organic materials will find widespread use in many technological applications. In the case of organic opto-electronic systems, the list of devices includes light emitting diodes (OLEDs), photovoltaic cells (OPVs), field-effect transistors (OFET), photorefractive materials for light manipulation, among others. These materials are also used for photonic applications: all-optical switching, modulators, optical correlators, plastic waveguides, all polymeric integrated circuits, solid-state lasers, and for biophotonic applications as in the case of the development of organic labels for multiphoton microscopy and photodynamic therapy. The advances in the developing of organic compounds with better mechanical, electrical, and optical (linear and non-linear) characteristics are of a great importance for this field. Here, we present the research on this area carried out at the Centro de Investigaciones en Óp-tica (CIO), in collaboration with Chemistry Departments of different institutions. This work focuses on the optical characterization of materials through several techniques such as TOF, FWM, TBC, THG Maker Fringes, HRS, Z-scan, and TPEF. Additionally, some applications, such as dynamic holography by using photorefractive polymers, and OPVs cells will be discussed.
Computational Modeling of Ultrafast Pulse Propagation in Nonlinear Optical Materials
Goorjian, Peter M.; Agrawal, Govind P.; Kwak, Dochan (Technical Monitor)
1996-01-01
There is an emerging technology of photonic (or optoelectronic) integrated circuits (PICs or OEICs). In PICs, optical and electronic components are grown together on the same chip. rib build such devices and subsystems, one needs to model the entire chip. Accurate computer modeling of electromagnetic wave propagation in semiconductors is necessary for the successful development of PICs. More specifically, these computer codes would enable the modeling of such devices, including their subsystems, such as semiconductor lasers and semiconductor amplifiers in which there is femtosecond pulse propagation. Here, the computer simulations are made by solving the full vector, nonlinear, Maxwell's equations, coupled with the semiconductor Bloch equations, without any approximations. The carrier is retained in the description of the optical pulse, (i.e. the envelope approximation is not made in the Maxwell's equations), and the rotating wave approximation is not made in the Bloch equations. These coupled equations are solved to simulate the propagation of femtosecond optical pulses in semiconductor materials. The simulations describe the dynamics of the optical pulses, as well as the interband and intraband.
Nonlinear Interferometric Vibrational Imaging (NIVI) with Novel Optical Sources
Boppart, Stephen A.; King, Matthew D.; Liu, Yuan; Tu, Haohua; Gruebele, Martin
Optical imaging is essential in medicine and in fundamental studies of biological systems. Although many existing imaging modalities can supply valuable information, not all are capable of label-free imaging with high-contrast and molecular specificity. The application of molecular or nanoparticle contrast agents may adversely influence the biological system under investigation. These substances also present ongoing concerns over toxicity or particle clearance, which must be properly addressed before their approval for in vivo human imaging. Hence there is an increasing appreciation for label-free imaging techniques. It is of primary importance to develop imaging techniques that can indiscriminately identify and quantify biochemical compositions to high degrees of sensitivity and specificity through only the intrinsic optical response of endogenous molecular species. The development and use of nonlinear interferometric vibrational imaging, which is based on the interferometric detection of optical signals from coherent anti-Stokes Raman scattering (CARS), along with novel optical sources, offers the potential for label-free molecular imaging.
Zhang, Bo
The past decade has witnessed astounding boom in telecommunication network traffic. With the emergence of multimedia over Internet, the high-capacity optical transport systems have started to shift focus from the core network towards the end users. This trend leads to diverse optical networks with transparency and reconfigurability requirement. As single channel data rate continues to increase and channel spacing continues to shrink for high capacity, high spectral efficiency, the workload on conventional electronic signal processing elements in the router nodes continues to build up. Performing signal processing functions in the optical domain can potentially alleviate the speed bottleneck if the unique optical properties are efficiently leveraged to assist electronic processing methodologies. Ultra-high bandwidth capability along with the promise for multi-channel and format-transparent operation make optical signal processing an attractive technology which is expected to have great impact on future optical networks. For optical signal processing applications in fiber-optic network and systems, a laudable goal would be to explore the unique nonlinear optical processes in novel photonic devices. This dissertation investigates novel optical signal processing techniques through simulations and experimental demonstrations, analyzes limitations of these nonlinear processing elements and proposes techniques to enhance the system performance or designs for functional photonic modules. Two key signal-processing building blocks for future optical networks, namely slow-light-based tunable optical delay lines and SOA-based high-speed wavelength converters, are presented in the first part of the dissertation. Phase preserving and spectrally efficient slow light are experimentally demonstrated using advanced modulation formats. Functional and novel photonic modules, such as multi-channel synchronizer and variable-bit-rate optical time division multiplexer are designed and
Lavrov, Roman; Peil, Michael; Jacquot, Maxime; Larger, Laurent; Udaltsov, Vladimir; Dudley, John
2009-08-01
We demonstrate experimentally how nonlinear optical phase dynamics can be generated with an electro-optic delay oscillator. The presented architecture consists of a linear phase modulator, followed by a delay line, and a differential phase-shift keying demodulator (DPSK-d). The latter represents the nonlinear element of the oscillator effecting a nonlinear transformation. This nonlinearity is considered as nonlocal in time since it is ruled by an intrinsic differential delay, which is significantly greater than the typical phase variations. To study the effect of this specific nonlinearity, we characterize the dynamics in terms of the dependence of the relevant feedback gain parameter. Our results reveal the occurrence of regular GHz oscillations (approximately half of the DPSK-d free spectral range), as well as a pronounced broadband phase-chaotic dynamics. Beyond this, the observed dynamical phenomena offer potential for applications in the field of microwave photonics and, in particular, for the realization of novel chaos communication systems. High quality and broadband phase-chaos synchronization is also reported with an emitter-receiver pair of the setup.
Nonlinear interaction of electromagnetic field with quantum plasma
Latyshev, A V
2014-01-01
The analysis of nonlinear interaction of transversal electromagnetic field with quantum collisionless plasma is carried out. Formulas for calculation electric current in quantum collisionless plasma at any temperature are deduced. It has appeared, that the nonlinearity account leads to occurrence of the longitudinal electric current directed along a wave vector. This second current is orthogonal to the known transversal classical current, received at the classical linear analysis. The case of degenerate electronic plasma is considered. It is shown, that for degenerate plasmas the electric current is calculated under the formula, not containing quadratures.
Meyers, Ronald E.; Deacon, Keith S.; Rosen, D.
2002-12-01
A new quantum optics tool for simulating quantum probability density functions resulting from the linear and nonlinear interaction of photons with atoms and with other photons is developed and presented. It can be used to design and simulate quantum optics experiments used in quantum communications, quantum computing, and quantum imaging. Examples of a photon interacting with linears systems of mirrors and beamsplitters are simulated. Nonlinear simulations of the interaction of three photons resulting in photon momentum entanglement is presented. The wavefunction is expanded in Fock states. Fock states cannot be represented by classical modeling and therefore, the results of our modeling can in general represent phenomena in both the linear and nonlinear cases which cannot be modeled by classical linear optics. The modeling presented here is more general than the classical linear optics. Models of atmospheric turbulence and their simulations are presented and demonstrate the potential for first principles physics quantum optics simulations through turbulence in realistic environments.
The nonlinear Schrödinger equation singular solutions and optical collapse
Fibich, Gadi
2015-01-01
This book is an interdisciplinary introduction to optical collapse of laser beams, which is modelled by singular (blow-up) solutions of the nonlinear Schrödinger equation. With great care and detail, it develops the subject including the mathematical and physical background and the history of the subject. It combines rigorous analysis, asymptotic analysis, informal arguments, numerical simulations, physical modelling, and physical experiments. It repeatedly emphasizes the relations between these approaches, and the intuition behind the results. The Nonlinear Schrödinger Equation will be useful to graduate students and researchers in applied mathematics who are interested in singular solutions of partial differential equations, nonlinear optics and nonlinear waves, and to graduate students and researchers in physics and engineering who are interested in nonlinear optics and Bose-Einstein condensates. It can be used for courses on partial differential equations, nonlinear waves, and nonlinear optics. Gadi Fib...
Laser Induced Nonlinear Optical Properties of Zinc Oxide Thin Film Prepared by Sol-Gel Method
Directory of Open Access Journals (Sweden)
Vinay Kumari
2011-01-01
Full Text Available Optical nonlinearities of spin coated ZnO thin film have been investigated by using single beam Z-Scan technique in the visible region. X- ray diffraction shows that all films are oriented along the c-axis direction of the hexagonal crystal structure. The average optical transmittance of all films is higher than 80 %. The nonlinear optical parameters viz. nonlinear absorption coefficient (β, nonlinear index of refraction (η2, nonlinear susceptibility (χ3, have been estimated using nanosecond laser pulses of second harmonic of Nd:YAG Laser. The value of nonlinear absorption coefficient β is estimated to be greater than the already reported value. The films clearly exhibit a-ve value of nonlinear refraction at 532 nm which is attributed to the two photon absorption and free carrier absorption. The presence of RSA in ZnO thin films inferes that ZnO is a potential material for the development of optical limiter.
Nonlinear effects in optical pumping of a cold and slow atomic beam
Porfido, N.
2015-10-12
By photoionizing hyperfine (HF) levels of the Cs state 62P3/2 in a slow and cold atom beam, we find how their population depends on the excitation laser power. The long time (around 180μs) spent by the slow atoms inside the resonant laser beam is large enough to enable exploration of a unique atom-light interaction regime heavily affected by time-dependent optical pumping. We demonstrate that, under such conditions, the onset of nonlinear effects in the population dynamics and optical pumping occurs at excitation laser intensities much smaller than the conventional respective saturation values. The evolution of population within the HF structure is calculated by numerical integration of the multilevel optical Bloch equations. The agreement between numerical results and experiment outcomes is excellent. All main features in the experimental findings are explained by the occurrence of “dark” and “bright” resonances leading to power-dependent branching coefficients.
Mukhopadhyay, S.; Ramasesha, S.
2009-08-01
We have used the density matrix renormalization group (DMRG) method to study the linear and nonlinear optical responses of first generation nitrogen based dendrimers with donor acceptor groups. We have employed Pariser-Parr-Pople Hamiltonian to model the interacting π electrons in these systems. Within the DMRG method we have used an innovative scheme to target excited states with large transition dipole to the ground state. This method reproduces exact optical gaps and polarization in systems where exact diagonalization of the Hamiltonian is possible. We have used a correction vector method which tacitly takes into account the contribution of all excited states, to obtain the ground state polarizibility, first hyperpolarizibility, and two photon absorption cross sections. We find that the lowest optical excitations as well as the lowest excited triplet states are localized. It is interesting to note that the first hyperpolarizibility saturates more rapidly with system size compared to linear polarizibility unlike that of linear polyenes.
Mukhopadhyay, S; Ramasesha, S
2009-08-21
We have used the density matrix renormalization group (DMRG) method to study the linear and nonlinear optical responses of first generation nitrogen based dendrimers with donor acceptor groups. We have employed Pariser-Parr-Pople Hamiltonian to model the interacting pi electrons in these systems. Within the DMRG method we have used an innovative scheme to target excited states with large transition dipole to the ground state. This method reproduces exact optical gaps and polarization in systems where exact diagonalization of the Hamiltonian is possible. We have used a correction vector method which tacitly takes into account the contribution of all excited states, to obtain the ground state polarizibility, first hyperpolarizibility, and two photon absorption cross sections. We find that the lowest optical excitations as well as the lowest excited triplet states are localized. It is interesting to note that the first hyperpolarizibility saturates more rapidly with system size compared to linear polarizibility unlike that of linear polyenes.
Nonlinear interaction of two waves in boundary-layer flows
Nayfeh, A. H.; Bozatli, A. N.
1980-01-01
First-order nonlinear interactions of Tollmien-Schlichting waves of different frequencies and initial amplitudes in boundary-layer flows are analyzed using the method of multiple scales. Numerical results for flow past a flat plate show that the spatial detuning wipes out resonant interactions unless the initial amplitudes are very large. Thus, a wave having a moderate amplitude has little influence on its subharmonic although it has a strong influence on its second harmonic. Moreover, two waves having moderate amplitudes have a strong influence on their difference frequency. The results show that the difference frequency can be very unstable when generated by the nonlinear interaction, even though it may be stable when introduced by itself in the boundary layer.
Nonlinear interactions isolated through scale synthesis in experimental wall turbulence
Duvvuri, Subrahmanyam; McKeon, Beverley
2016-07-01
An experimental investigation of nonlinear scale interactions in a forced turbulent boundary layer is presented here. A dynamic wall perturbation mechanism was used to externally force two distinct large-scale synthetic modes with well-defined spatial and temporal wave numbers in a fully turbulent flow. The focus is on characterizing the nonlinear flow response at triadically consistent wave numbers that arises from the direct interactions of the two synthetic modes. These experimental results isolate triadic scale interactions in wall turbulence in a unique fashion, and provide the ability to explore the dynamics of scale coupling in a systematic and detailed manner. The ideas advanced here are intended to contribute towards modeling efforts of high-Reynolds-number wall turbulence.
Generalized Ghost Dark Energy with Non-Linear Interaction
Ebrahimi, E; Mehrabi, A; Movahed, S M S
2016-01-01
In this paper we investigate ghost dark energy model in the presence of non-linear interaction between dark energy and dark matter. The functional form of dark energy density in the generalized ghost dark energy (GGDE) model is $\\rho_D\\equiv f(H, H^2)$ with coefficient of $H^2$ represented by $\\zeta$ and the model contains three free parameters as $\\Omega_D, \\zeta$ and $b^2$ (the coupling coefficient of interactions). We propose three kinds of non-linear interaction terms and discuss the behavior of equation of state, deceleration and dark energy density parameters of the model. We also find the squared sound speed and search for signs of stability of the model. To compare the interacting GGDE model with observational data sets, we use more recent observational outcomes, namely SNIa, gamma-ray bursts, baryonic acoustic oscillation and the most relevant CMB parameters including, the position of acoustic peaks, shift parameters and redshift to recombination. For GGDE with the first non-linear interaction, the j...
Carrillo-Delgado, C.; García-Gil, C. I.; Trejo-Valdez, M.; Torres-Torres, C.; García-Merino, J. A.; Martínez-Gutiérrez, H.; Khomenko, A. V.; Torres-Martínez, R.
2016-01-01
Measurements of the third-order nonlinear optical properties exhibited by a ZnO thin solid film deposited on a SnO2 substrate are presented. The samples were prepared by a spray pyrolysis processing route. Scanning electron microscopy analysis and UV-Vis spectroscopy studies were carried out. The picosecond response at 1064 nm was explored by the z-scan technique. A large optical Kerr effect with two-photon absorption was obtained. The inhibition of the nonlinear optical absorption together with a noticeable enhancement in the optical Kerr effect in the sample was achieved by the incorporation of Au nanoparticles into the ZnO film. Additionally, a two-wave mixing configuration at 532 nm was performed and an optical Kerr effect was identified as the main cause of the nanosecond third-order optical nonlinearity. The relaxation time of the photothermal response of the sample was estimated to be about 1 s when the sample was excited by nanosecond single-shots. The rotation of the sample during the nanosecond two-wave mixing experiments was analyzed. It was stated that a non-monotonic relation between rotating frequency and pulse repetition rate governs the thermal contribution to the nonlinear refractive index exhibited by a rotating film. Potential applications for switching photothermal interactions in rotating samples can be contemplated. A rotary logic system dependent on Kerr transmittance in a two-wave mixing experiment was proposed.
Chiro-optic and nonlinear optical studies of bridged triarylamine heterohelicenes; A DFT study
Islam, Nasarul; Pandith, Altaf Hussain
2017-08-01
Density Functional Theory at B3PW91/6-311G (d, p) level was employed to analyze the spectral properties and nonlinear optical response of the oxo and thia-bridged triarylamine heterohelicenes. The energy calculations of optimized geometries reveals that the M and P isomeric forms of heterohelicenes of 1, 2, 3 and 4 are enantiomers, while as for 5, 6 and 7 they are atropisomers. The simulated Infrared and Vibrational circular dichroism spectra in the mid-infrared region (1300-1650 cm-1) display peaks, having contribution from out-of-phase stretching of the three fused aromatic rings and contribution from the three Nsbnd C bond stretching. In addition to these peaks M-7 displays peak corresponds to bending of Hsbnd Csbnd H of terminal methoxy group. In this study we have observed the oxo-bridged heterohelicenes displays higher values of hyperpolarizability as compared to thia-bridged heterohelicenes. In case of M-5, M-6 and M-7 the calculation reveals that with increase in electron donating capacity of substituent the hyperpolarizability increase due to decrease in optical band gap. Therefore, the oxo- and thia-bridged heterohelicenes can act as good raw material for nonlinear optical device and their nonlinear optical response can be enhanced by the extension in π-conjugation or addition of electron donating substituents.
Nonlinear optical properties of natural laccaic acid dye studied using Z-scan technique
CSIR Research Space (South Africa)
Zongo, S
2015-08-01
Full Text Available We have investigated the nonlinear optical properties, including the optical limiting behaviour for five different concentrations of laccaic acid dye in solution and a thin film obtained through doping in poly (methyl methacrylate) (PMMA) polymer...
Nonlinear wave-wave interactions and wedge waves
Institute of Scientific and Technical Information of China (English)
Ray Q.Lin; Will Perrie
2005-01-01
A tetrad mechanism for exciting long waves,for example edge waves,is described based on nonlinear resonant wave-wave interactions.In this mechanism,resonant interactions pass energy to an edge wave,from the three participating gravity waves.The estimated action flux into the edge wave can be orders of magnitude greater than the transfer fluxes derived from other competing mechanisms,such as triad interactions.Moreover,the numerical results show that the actual transfer rates into the edge wave from the three participating gravity waves are two-to three- orders of magnitude greater than bottom friction.
Exploring Divisibility and Summability of 'Photon' Wave Packets in Nonlinear Optical Phenomena
Prasad, Narasimha; Roychoudhuri, Chandrasekhar
2009-01-01
Formulations for second and higher harmonic frequency up and down conversions, as well as multi photon processes directly assume summability and divisibility of photons. Quantum mechanical (QM) interpretations are completely congruent with these assumptions. However, for linear optical phenomena (interference, diffraction, refraction, material dispersion, spectral dispersion, etc.), we have a profound dichotomy. Most optical engineers innovate and analyze all optical instruments by propagating pure classical electromagnetic (EM) fields using Maxwell s equations and gives only lip-service to the concept "indivisible light quanta". Further, irrespective of linearity or nonlinearity of the phenomena, the final results are always registered through some photo-electric or photo-chemical effects. This is mathematically well modeled by a quadratic action (energy absorption) relation. Since QM does not preclude divisibility or summability of photons in nonlinear & multi-photon effects, it cannot have any foundational reason against these same possibilities in linear optical phenomena. It implies that we must carefully revisit the fundamental roots behind all light-matter interaction processes and understand the common origin of "graininess" and "discreteness" of light energy.
A high repetition rate experimental setup for quantum non-linear optics with cold Rydberg atoms
Busche, Hannes; Ball, Simon W.; Huillery, Paul
2016-12-01
Using electromagnetically induced transparency and photon storage, the strong dipolar interactions between Rydberg atoms and the resulting dipole blockade can be mapped onto light fields to realise optical non-linearities and interactions at the single photon level. We report on the realisation of an experimental apparatus designed to study interactions between single photons stored as Rydberg excitations in optically trapped microscopic ensembles of ultracold 87Rb atoms. A pair of in-vacuum high numerical aperture lenses focus excitation and trapping beams down to 1 μm, well below the Rydberg blockade. Thanks to efficient magneto-optical trap (MOT) loading from an atomic beam generated by a 2D MOT and the ability to recycle the microscopic ensembles more than 20000 times without significant atom loss, we achieve effective repetition rates exceeding 110 kHz to obtain good photon counting statistics on reasonable time scales. To demonstrate the functionality of the setup, we present evidence of strong photon interactions including saturation of photon storage and the retrieval of non-classical light. Using in-vacuum antennae operating at up to 40 GHz, we perform microwave spectroscopy on photons stored as Rydberg excitations and observe an interaction induced change in lineshape depending on the number of stored photons.
Seeger, Markus; Karlas, Angelos; Soliman, Dominik; Pelisek, Jaroslav; Ntziachristos, Vasilis
2017-03-01
Carotid atheromatosis is causally related to stroke, a leading cause of disability and death. We present the analysis of a human carotid atheroma using a novel hybrid microscopy system that combines optical-resolution optoacoustic (photoacoustic) microscopy and several non-linear optical microscopy modalities (second and third harmonic generation, as well as, two-photon excitation fluorescence) to achieve a multimodal examination of the extracted tissue within the same imaging framework. Our system enables the label-free investigation of atheromatous human carotid tissue with a resolution of about 1 μm and allows for the congruent interrogation of plaque morphology and clinically relevant constituents such as red blood cells, collagen, and elastin. Our data reveal mutual interactions between blood embeddings and connective tissue within the atheroma, offering comprehensive insights into its stage of evolution and severity, and potentially facilitating the further development of diagnostic tools, as well as treatment strategies.
Budker, D
2003-01-01
Recent work on Lambda-resonances in alkali metal vapors (E. Mikhailov, I. Novikova, Yu. V. Rostovtsev, and G. R. Welch, quant-ph/0309171, and references therein) has revealed a novel type of electromagnetically induced absorption resonance that occurs in three-level systems under specific conditions normally associated with electromagnetically induced transparency. In this note, we show that these resonances have a direct analog in nonlinear magneto-optics, and support this conclusion with a calculation for a J=1->J'=0 system interacting with a single nearly circularly polarized light field in the presence of a weak longitudinal magnetic field.
Polarization-selective optical nonlinearities in cold Rydberg atoms
Wu, Jin-Hui; Artoni, M.; La Rocca, G. C.
2015-12-01
We study the interaction between a probe and a trigger weak fields in a sample of cold rubidium atoms in the presence of a coupling and a dressing strong fields. Dipole Rydberg blockade may occur and can be set to depend on the probe and trigger polarizations giving rise to diverse regimes of electromagnetically induced transparency (EIT) with a concomitant small probe and trigger absorption and dispersion. This is shown to be relevant to the implementation of polarization conditional probe and trigger cross nonlinearities in cold Rydberg atoms.
Pysher, Matthew; Bahabad, Alon; Peng, Peng; Arie, Ady; Pfister, Olivier
2010-02-15
We report the successful design and experimental implementation of three coincident nonlinear interactions, namely ZZZ (type 0), ZYY (type I), and YYZ/YZY (type II) second-harmonic generation of 780 nm light from a 1560 nm pump beam in a single, multigrating, periodically poled KTiOPO(4) crystal. The resulting nonlinear medium is the key component for making a scalable quantum computer over the optical frequency comb of a single optical parametric oscillator.
Kazemi, Mehdi Mohammad; Mazaheri Tehrani, Alireza; Zeb Khan, Tahir; Namboodiri, Mahesh; Materny, Arnulf
2015-12-01
A Toffoli logic gate (CCNOT gate) is a universal reversible logic gate from which all other reversible gates can be constructed. It has a three-bit input and output. The goal of our work was to realize a Toffoli gate where all inputs and outputs are realized optically, which allows for ultrafast switching processes. We demonstrate experimentally that a Toffoli logic gate can be created based on nonlinear multi-wave interactions of light with matter. Using femtosecond laser pulses, the all-optical Toffoli gate is based on the coherence of the optical signals produced via the nonlinear optical processes. Sum frequency (SF) and second harmonic (SH) generations are combined in such a way so as to yield the complete truth table of the universal reversible logic gate.
Complete elimination of nonlinear light-matter interactions with broadband ultrafast laser pulses
DEFF Research Database (Denmark)
Shu, Chuan-Cun; Dong, Daoyi; Petersen, Ian R.
2017-01-01
nonlinear interactions of ultrafast laser pulses with quantum systems. That is, a completely linear response of the system with respect to the spectral energy density of the incident light at the transition frequency can be obtained for all transition probabilities between 0 and 100% in multilevel quantum......The absorption of a single photon that excites a quantum system from a low to a high energy level is an elementary process of light-matter interaction, and a route towards realizing pure single-photon absorption has both fundamental and practical implications in quantum technology. Due to nonlinear...... optical effects, however, the probability of pure single-photon absorption is usually very low, which is particularly pertinent in the case of strong ultrafast laser pulses with broad bandwidth. Here we demonstrate theoretically a counterintuitive coherent single-photon absorption scheme by eliminating...
Orbelli Biroli, Alessio; Tessore, Francesca; Righetto, Stefania; Forni, Alessandra; Macchioni, Alceo; Rocchigiani, Luca; Pizzotti, Maddalena; Di Carlo, Gabriele
2017-06-05
A series of 5,15 push-pull meso-diarylzinc(II) porphyrinates, carrying one or two -COOH or -COOCH3 acceptor groups and a -OCH3 or a -N(CH3)2 donor group, show in N,N-dimethylformamide and CHCl3 solutions a negative and solvent-dependent second-order nonlinear-optical (NLO) response measured by the electric-field-induced second-harmonic generation (EFISH) technique, different from the structurally related zinc(II) porphyrinate carrying a -N(CH3)2 donor group and a -NO2 acceptor group, where a still solvent-dependent but positive EFISH second-order response was previously reported. Moreover, when a -N(CH3)2 donor group and a -COOH acceptor group are part of a sterically hindered 2,12 push-pull β-pyrrolic-substituted tetraarylzinc(II) porphyrinate, the EFISH response is positive and solvent-independent. In order to rationalize these rather intriguing series of observations, EFISH measurements have been integrated by electronic absorption and IR spectroscopic investigations and by density functional theory (DFT) and coupled-perturbed DFT theoretical and (1)H pulsed-gradient spin-echo NMR investigations, which prompt that the significant concentration effects and the strong influence of the solvent nature on the NLO response are originated by a complex whole of different aggregation processes induced by the -COOH group.
Nonlinear optical properties of Au-Ag core-shell nanorods for all-optical switching
Zhang, Luman; Dai, Hongwei; Wang, Xia; Yao, Linhua; Ma, Zongwei; Han, Jun-Bo
2017-09-01
Au-Ag core-shell nanorods with surface plasmon resonance wavelengths of 760-840 nm were prepared. Wavelength-dependent nonlinear absorption coefficients (β) and nonlinear refractive indices (γ) of the nanorods were measured by using Z-scan techniques. The corresponding one-photon and two-photon figures of merit (W and T) were calculated from β and γ. The results show that the requirements of W > 1 and T < 1 for the application of all-optical switching could be achieved for all the samples over a broad wavelength range. These observations make the Au-Ag core-shell nanorods a good candidate for all-optical switching devices.
All-optical switching and nonlinear optical properties of HBT in ethanol solution
Institute of Scientific and Technical Information of China (English)
Zheng Jia-Jin; Zhang Gui-Lan; Guo Yang-Xue; Li Xiang-Ping; Chen Wen-Ju
2007-01-01
This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He-Ne signal beam at 632.8 nm with 2-(2'-hydroxyphenyl)benzothiazole (HBT) in ethanol solution. The origins of the optical switching effect were discussed. By the study of nonlinear optical properties for HBT in ethanol solvent, this paper verified that the excited-state intramolecular proton transfer (ESIPT) effect of HBT and the thermal effect of solvent worked on quite different time scales and together induced the change of the refractive index of HBT solution, leading to the signal beam deflection. The results indicated that the HBT molecule could be an excellent candidate for high-speed and high-sensitive optical switching devices.
Directory of Open Access Journals (Sweden)
2007-03-01
Full Text Available Transparent Nonlinear Optical (NLO inorganic/organic (polyimide/silica hybrid composites with covalent links between the inorganic and the organic networks were prepared by the sol-gel method. The silica content in the hybrid films was varied from 0 to 22.5/wt%. The prepared PI hybrids were characterized by IR, UV-Vis, Thermogravimetric analysis (TGA, X-ray diffraction (XRD, Scanning Electron Microscopy (SEM and Transmission Electron Microscopy (TEM. They exhibited fair good optical transparency. The SiO2 phase was well dispersed in the polymer matrix. DSC and TGA results showed that these hybrid materials had excellent thermal stability. The polymer solutions could be spin coated on the indium-tin-oxide (ITO glass to form optical quality thin films. The electro-optic coefficients (γ33 at the wavelength of 832 nm for polymer thin films poled were in the range of 19-27 pm/V.
Diffractive optics based four-wave, six-wave, ..., nu-wave nonlinear spectroscopy.
Miller, R J Dwayne; Paarmann, Alexander; Prokhorenko, Valentyn I
2009-09-15
A detailed understanding of chemical processes requires information about both structure and dynamics. By definition, a reaction involves nonstationary states and is a dynamic process. Structure describes the atomic positions at global minima in the nuclear potential energy surface. Dynamics are related to the anharmonicities in this potential that couple different minima and lead to changes in atomic positions (reactions) and correlations. Studies of molecular dynamics can be configured to directly access information on the anharmonic interactions that lead to chemical reactions and are as central to chemistry as structural information. In this regard, nonlinear spectroscopies have distinct advantages over more conventional linear spectroscopies. Because of this potential, nonlinear spectroscopies could eventually attain a comparable level of importance for studying dynamics on the relevant time scales to barrier crossings and reactive processes as NMR has for determining structure. Despite this potential, nonlinear spectroscopy has not attained the same degree of utility as linear spectroscopy largely because nonlinear studies are more technically challenging. For example, unlike the linear spectrometers that exist in almost all chemistry departments, there are no "black box" four-wave mixing spectrometers. This Account describes recent advances in the application of diffractive optics (DOs) to nonlinear spectroscopy, which reduces the complexity level of this technology to be closer to that of linear spectroscopy. The combination of recent advances in femtosecond laser technology and this single optic approach could bring this form of spectroscopy out of the exclusive realm of specialists and into the general user community. However, the real driving force for this research is the pursuit of higher sensitivity limits, which would enable new forms of nonlinear spectroscopy. This Account chronicles the research that has now extended nonlinear spectroscopy to six
Femtojoule-Scale All-Optical Latching and Modulation via Cavity Nonlinear Optics
Kwon, Yeong-Dae; Armen, Michael A.; Mabuchi, Hideo
2013-11-01
We experimentally characterize Hopf bifurcation phenomena at femtojoule energy scales in a multiatom cavity quantum electrodynamical (cavity QED) system and demonstrate how such behaviors can be exploited in the design of all-optical memory and modulation devices. The data are analyzed by using a semiclassical model that explicitly treats heterogeneous coupling of atoms to the cavity mode. Our results highlight the interest of cavity QED systems for ultralow power photonic signal processing as well as for fundamental studies of mesoscopic nonlinear dynamics.
Optical and nonlinear optical properties of orthorhombic BiB3O6
Cherepakhin, A. V.; Zaitsev, A. I.; Aleksandrovsky, A. S.; Zamkov, A. V.
2012-03-01
Dispersion of refraction coefficients of orthorhombic BiB3O6 in the wavelength range between 435.8 and 1060 nm is studied, nonlinear optical coefficients are determined, and phase matching angles, angular and spectral bandwidths for second harmonic generation processes are calculated. δ-BiBO may be suitable for doubling of lasers with a wavelength in the 1.3 μm region as well as the matrix for self-doubling lasing media.
Impact of nonlinear effective interactions on GFT quantum gravity condensates
Pithis, Andreas G A; Tomov, Petar
2016-01-01
We present the numerical analysis of effectively interacting Group Field Theory (GFT) models in the context of the GFT quantum gravity condensate analogue of the Gross-Pitaevskii equation for real Bose-Einstein condensates including combinatorially local interaction terms. Thus we go beyond the usually considered construction for free models. More precisely, considering such interactions in a weak regime, we find solutions for which the expectation value of the number operator N is finite, as in the free case. When tuning the interaction to the strongly nonlinear regime, however, we obtain solutions for which N grows and eventually blows up, which is reminiscent of what one observes for real Bose-Einstein condensates, where a strong interaction regime can only be realized at high density. This behaviour suggests the breakdown of the Bogoliubov ansatz for quantum gravity condensates and the need for non-Fock representations to describe the system when the condensate constituents are strongly correlated. Furthe...
Garrett, Kerry
Organic electro-optic (OEO) materials integrated into silicon-organic hybrid (SOH) devices afford significant improvements in size, weight, power, and bandwidth (SWAP) performance of integrated electronic/photonic systems critical for current and next generation telecommunication, computer, sensor, transportation, and defense technologies. Improvement in molecular first hyperpolarizability, and in turn electro-optic activity, is crucial to further improvement in the performance of SOH devices. The timely preparation of new chromophores with improved molecular first hyperpolarizability requires theoretical guidance; however, common density functional theory (DFT) methods often perform poorly for optical properties in systems with substantial intramolecular charge transfer character. The first part of this dissertation describes the careful evaluation of popular long-range correction (LC) and range-separated hybrid (RSH) density functional theory (DFT) for definition of structure/function relationships crucial for the optimization of molecular first hyperpolarizability, beta. In particular, a benchmark set of well-characterized OEO chromophores is used to compare calculated results with the corresponding experimentally measured linear and nonlinear optical properties; respectively, the wavelength of the peak one-photon absorption energy, lambdamax, and beta. A goal of this work is to systematically determine the amount of exact exchange in LC/RSH-DFT methods required for accurately computing these properties for a variety OEO chromophores. High-level electron correlation (post-Hartree-Fock) methods are also investigated and compared with DFT. Included are results for the computation of beta using second-order Moller-Plesset perturbation theory (MP2) and the double-hybrid method, B2PLYP. The second part of this work transitions from single-molecule studies to computing bulk electronic and nonlinear optical properties of molecular crystals and isotropic ensembles of a
Indian Academy of Sciences (India)
S Venugopal Rao; P T Anusha; L Giribabu; Surya P Tewari
2010-11-01
We present our experimental results on the picosecond nonlinear optical (NLO) studies of symmetrical and unsymmetrical phthalocyanines, examined using the Z-scan technique. Both the open-aperture and closed-aperture Z-scan curves for three samples were recorded and the nonlinear coefficients were extracted from the theoretical fits. The nonlinear absorption/refraction contribution from the solvent was also identified. The observed open aperture behaviour for these molecules is understood in terms of the absorption coefficients of these molecules near 800 nm and the peak intensities used. It is established that these phthalocyanines exhibit large optical nonlinearities and, hence, are suitable for optical limiting applications.
Enhanced nonlinear optical response of one-dimensional metal-dielectric photonic crystals.
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.
Nonlinear Interaction of Transversal Modes in a CO2 Laser
Lopez-Ruiz, Ricardo; Mindlin, G. B.; Perez-Garcia, C.; Tredicce, J. R.
2002-01-01
We show the possibility of achieving experimentally a Takens-Bogdanov bifurcation for the nonlinear interaction of two transverse modes ($l = \\pm 1$) in a $CO_2$ laser. The system has a basic O(2) symmetry which is perturbed by some symmetry-breaking effects that still preserve the $Z_2$ symmetry. The pattern dynamics near this codimension two bifurcation under such symmetries is described. This dynamics changes drastically when the laser properties are modified.
Energy Technology Data Exchange (ETDEWEB)
Golde, Daniel
2010-06-22
In the major part of this Thesis, we discuss the linear THz response of semiconductor nanostructures based on a microscopic theory. Here, two different problems are investigated: intersubband transitions in optically excited quantum wells and the THz plasma response of two-dimensional systems. In the latter case, we analyze the response of correlated electron and electron-hole plasmas. Extracting the plasma frequency from the linear response, we find significant deviations from the commonly accepted two-dimensional plasma frequency. Besides analyzing the pure plasma response, we also consider an intermediate regime where the response of the electron-hole plasma consists of a mixture of plasma contributions and excitonic transitions. A quantitative experiment-theory comparison provides novel insights into the behavior of the system at the transition from one regime to the other. The discussion of the intersubband transitions mainly focuses on the coherent superposition of the responses from true THz transitions and the ponderomotively accelerated carriers. We present a simple method to directly identify ponderomotive effects in the linear THz response. Apart from that, the excitonic contributions to intersubband transitions are investigated. The last part of the present Thesis deals with a completely different regime. Here, the extreme nonlinear optical response of low-dimensional semiconductor structures is discussed. Formally, extreme nonlinear optics describes the regime of light-matter interaction where the exciting field is strong enough such that the Rabi frequency is comparable to or larger than the characteristic transition frequency of the investigated system. Here, the Rabi frequency is given by the product of the electrical field strength and the dipole-matrix element of the respective transition. Theoretical investigations have predicted a large number of novel nonlinear effects arising for such strong excitations. Some of them have been observed in
Nonlinear optical response in Kronig-Penney type graphene superlattice in terahertz regime
Jiang, Lijuan; Yuan, Rui-Yang; Zhao, Xin; Lv, Jing; Yan, Hui
2015-05-01
The terahertz nonlinear optical response in Kronig-Penney (KP) type graphene superlattice is demonstrated. The single-, triple- and quintuple-frequencies of the fifth-order nonlinear responses are investigated for different frequencies and temperatures with the angle φ along the periodicity of the superlattice toward the external field tuning from 0 to π/2. The results show that the fifth-order nonlinear optical conductance of graphene superlattice is enhanced in the terahertz regime when φ = 0, i.e. an external field is applied along the periodicity of the superlattice. The fifth-order nonlinear optical conductances at φ = 0 for different frequencies and temperatures are calculated. The results show that the nonlinear optical conductance is enhanced in low frequency and low temperature. Our results suggest that KP type graphene superlattices are preferred structures for developing graphene-based nonlinear photonics and optoelectronics devices.
Performance emulation and parameter estimation for nonlinear fibre-optic links
DEFF Research Database (Denmark)
Piels, Molly; Porto da Silva, Edson; Zibar, Darko
2016-01-01
Fibre-optic communication systems, especially when operating in the nonlinear regime, generally do not perform exactly as theory would predict. A number of methods for data-based evaluation of nonlinear fibre-optic link parameters, both for accurate performance emulation and optimization...
Inclusion Tuning of Nonlinear Optical Materials: KTP (Potassium Titanyl Phosphate) Isomorphs
1988-06-01
o OFCE OF NAVAL RESEARCH Contract N00014-87-K-0457 V R&T Code 4134015-01 0) Technical. Report No. 23 "Inclusion Tuning of Nonlinear Optical Materials : KIP...bry block nuum.ber) see attached #11 Inclusion Tuning of Nonlinear Optical Materials : KTP Isomorphs * Q1 UISTRISUTION/AVAII..ASILITY 00 ABSTRACT 21
Eye/Sensor Protection against Laser Irradiation Organic Nonlinear Optical Materials
1989-06-12
Recent developments in organic nonlinear optical materials for application to eye and sensor protection are reviewed. This compendium includes a...noteworthy organic third-order nonlinear optical materials is included as an appendix. Lasers are playing an important and increasing role in modern
Basic Studies of Nonlinear Optical Materials for Eye and Sensor Protection
2004-03-10
1 BASIC STUDIES OF NONLINEAR OPTICAL MATERIALS FOR EYE AND SENSOR PROTECTION I. Abstract: We have studied the spectroscopy, kinetics and...study liquid or solid materials from CW to 100x10-15 seconds. Basic Studies of Nonlinear Optical Materials for Eye and Sensor Protection
Performance emulation and parameter estimation for nonlinear fibre-optic links
DEFF Research Database (Denmark)
Piels, Molly; Porto da Silva, Edson; Zibar, Darko;
2016-01-01
Fibre-optic communication systems, especially when operating in the nonlinear regime, generally do not perform exactly as theory would predict. A number of methods for data-based evaluation of nonlinear fibre-optic link parameters, both for accurate performance emulation and optimization, are rev...
Printed organic smart devices characterized by nonlinear optical
DEFF Research Database (Denmark)
Pastorelli, Francesco; Accanto, Nicolo; Jørgensen, Mikkel
2017-01-01
In this study, we demonstrate that nonlinear optical microscopy is a promising technique to characterize organic printed electronics. Using ultrashort laser pulses we stimulate two-photon absorption in a roll coated polymer semiconductor and map the resulting two-photon induced photoluminescence....... With this technique, we can recognize different nanomaterials and we propose that the TPPL is a good indicator to map and monitor the charge carrier density and the molecular packing of the printed polymer material. Importantly, simple calculations based on the signal levels, suggest that this technique can...... be extended to the real time mapping of the polymer semiconductor film, even during the printing process, in which the high printing speed poses the need for equally high acquisition rates....
Ultrafast third-order nonlinear optical response of pyrene derivatives
Shi, Yufang; Li, Zhongguo; Fang, Yu; Sun, Jinyu; Zhao, Minggen; Song, Yinglin
2017-05-01
Two mono-substituted pyrene derivatives with delocalized electron system 1-(pyren-1-yl)-3-(4-Methyl thiophene-2-yl) acrylic ketone (13#) and 1-(pyren-1-yl)-3-(4-bromo thiophene-2-yl) acrylic ketone (15#) were successfully synthesized. The resultant compounds were characterized by nuclear magnetic resonance (NMR), infrared spectroscopy (IR), high resolution mass spectrum (HR-MS), and UV-vis spectra. The third-order nonlinear optical properties of the compounds were investigated using Z-scan technique with femtosecond laser pulses at 500 nm and 700 nm, respectively. Both of the compounds showed a decrease in transmittance about the focus, which are typical of two-photon absorption. It was found that the two-photon absorption behavior of the pyrene derivatives were modified by substituents on thiophene ring. These results indicate that both compounds can be promising candidates for future optoelectronic and bio-imaging applications.
Superior optical nonlinearity of an exceptional fluorescent stilbene dye
Energy Technology Data Exchange (ETDEWEB)
He, Tingchao [College of Physics Science and Technology, Shenzhen University, Shenzhen 518060 (China); Division of Physics and Applied Physics, Centre for Disruptive Photonic Technologies (CDPT), School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore); Sreejith, Sivaramapanicker; Zhao, Yanli [Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore); Gao, Yang; Grimsdale, Andrew C. [School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore 639798 (Singapore); Lin, Xiaodong, E-mail: linxd@szu.edu.cn, E-mail: hdsun@ntu.edu.sg [College of Physics Science and Technology, Shenzhen University, Shenzhen 518060 (China); Sun, Handong, E-mail: linxd@szu.edu.cn, E-mail: hdsun@ntu.edu.sg [Division of Physics and Applied Physics, Centre for Disruptive Photonic Technologies (CDPT), School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)
2015-03-16
Strong multiphoton absorption and harmonic generation in organic fluorescent chromophores are, respectively, significant in many fields of research. However, most of fluorescent chromophores fall short of the full potential due to the absence of the combination of such different nonlinear upconversion behaviors. Here, we demonstrate that an exceptional fluorescent stilbene dye could exhibit efficient two- and three-photon absorption under the excitation of femtosecond pulses in solution phase. Benefiting from its biocompatibility and strong excited state absorption behavior, in vitro two-photon bioimaging and superior optical limiting have been exploited, respectively. Simultaneously, the chromophore could generate efficient three-photon excited fluorescence and third-harmonic generation (THG) when dispersed into PMMA film, circumventing the limitations of classical fluorescent chromophores. Such chromophore may find application in the production of coherent light sources of higher photon energy. Moreover, the combination of three-photon excited fluorescence and THG can be used in tandem to provide complementary information in biomedical studies.
Superior optical nonlinearity of an exceptional fluorescent stilbene dye
He, Tingchao; Sreejith, Sivaramapanicker; Gao, Yang; Grimsdale, Andrew C.; Zhao, Yanli; Lin, Xiaodong; Sun, Handong
2015-03-01
Strong multiphoton absorption and harmonic generation in organic fluorescent chromophores are, respectively, significant in many fields of research. However, most of fluorescent chromophores fall short of the full potential due to the absence of the combination of such different nonlinear upconversion behaviors. Here, we demonstrate that an exceptional fluorescent stilbene dye could exhibit efficient two- and three-photon absorption under the excitation of femtosecond pulses in solution phase. Benefiting from its biocompatibility and strong excited state absorption behavior, in vitro two-photon bioimaging and superior optical limiting have been exploited, respectively. Simultaneously, the chromophore could generate efficient three-photon excited fluorescence and third-harmonic generation (THG) when dispersed into PMMA film, circumventing the limitations of classical fluorescent chromophores. Such chromophore may find application in the production of coherent light sources of higher photon energy. Moreover, the combination of three-photon excited fluorescence and THG can be used in tandem to provide complementary information in biomedical studies.
Nonlinear optical imaging characteristics in rat tail tendon
Liu, N. R.; Zhang, X. Z.; Qiu, Y. S.; Chen, R.
2013-04-01
The aim of this study was to examine the characteristics of skeletal muscle fibers in tail tendons, explore the content of intrinsic components at different depths and ascertain the optimum excitation wavelength, which will help to establish a relationship between diagnosis and therapy and the tendon injury. A multiphoton microscopic imaging system was used to achieve the images and spectra via an imaging mode and a Lambda mode, respectively. This work demonstrates that the skeletal muscle fibers of the tail tendon are in good order. Second harmonic generation (SHG) and two-photon excited fluorescence (TPEF) signals originating from certain intrinsic components are varied with depth, and the SHG/TPEF intensity ratios are varied at different excitation wavelengths. Below 800 nm is the optimum for cell TPEF, while above 800 nm is the optimum for SHG. With the development of imaging techniques, a nonlinear optical imaging system will be helpful to represent the functional behaviors of tissue related to tendon injury.
Properties of nonreciprocal light propagation in a nonlinear optical isolator
Roy, Dibyendu
2016-01-01
Light propagation in a nonlinear optical medium is nonreciprocal for spatially asymmetric linear permittivity. We here examine physical mechanism and properties of such nonreciprocity (NR). For this, we calculate transmission of light through a two-level atom asymmetrically coupled to light inside open waveguides. We determine the critical intensity of incident light for maximum NR and a dependence of the corresponding NR on asymmetry in the coupling. Surprisingly, we find that it is mainly coherent elastic scattering compared to incoherent scattering of incident light which causes maximum NR near the critical intensity. We also show a higher NR of an incident light in the presence of an additional weak light at the opposite port.
Nonlinear Optical Microscopy Signal Processing Strategies in Cancer
Adur, Javier; Carvalho, Hernandes F; Cesar, Carlos L; Casco, Víctor H
2014-01-01
This work reviews the most relevant present-day processing methods used to improve the accuracy of multimodal nonlinear images in the detection of epithelial cancer and the supporting stroma. Special emphasis has been placed on methods of non linear optical (NLO) microscopy image processing such as: second harmonic to autofluorescence ageing index of dermis (SAAID), tumor-associated collagen signatures (TACS), fast Fourier transform (FFT) analysis, and gray level co-occurrence matrix (GLCM)-based methods. These strategies are presented as a set of potential valuable diagnostic tools for early cancer detection. It may be proposed that the combination of NLO microscopy and informatics based image analysis approaches described in this review (all carried out on free software) may represent a powerful tool to investigate collagen organization and remodeling of extracellular matrix in carcinogenesis processes. PMID:24737930