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Sample records for erbium doped fibre

  1. High-performace cladding-pumped erbium-doped fibre laser and amplifier

    International Nuclear Information System (INIS)

    Kotov, L V; Likhachev, M E; Bubnov, M M; Medvedkov, O I; Lipatov, D S; Vechkanov, N N; Guryanov, Aleksei N

    2012-01-01

    We report cladding-pumped erbium-doped fibre laser and amplifier configurations. Through fibre design optimisation, we have achieved a record-high laser slope efficiency, 40 % with respect to absorbed pump power (λ = 976 nm), and an output power of 7.5 W. The erbium-doped fibre amplifier efficiency reaches 32 %.

  2. Effect of temperature on the active properties of erbium-doped optical fibres

    Energy Technology Data Exchange (ETDEWEB)

    Kotov, L V [Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow Region (Russian Federation); Ignat' ev, A D [FORC - Photonics group, Moscow (Russian Federation); Bubnov, M M; Likhachev, M E [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation)

    2016-03-31

    We have studied the effect of heating on the performance of erbium-doped fibre based devices and determined temperaturedependent absorption and emission cross sections of the erbium ion in silica glass. The results demonstrate that heating of fibres in claddingpumped high-power (∼100 W) erbium-doped fibre lasers causes no significant decrease in their efficiency. In contrast, superluminescent sources operating in the long-wavelength region (1565 – 1610 nm) are extremely sensitive to temperature changes. (fiber optics)

  3. A Continuously Tunable Erbium-Doped Fibre Laser Using Tunable Fibre Bragg Gratings and Optical Circulator

    International Nuclear Information System (INIS)

    Peng, Liu; Feng-Ping, Yan; Jian, Li; Lin, Wang; Ti-Gang, Ning; Tao-Rong, Gong; Shui-Sheng, Jian

    2008-01-01

    A continuously tunable erbium-doped fibre laser (TEDFL) based on tunable fibre Bragger grating (TFBG) and a three-port optical circulator (OC) is proposed and demonstrated. The OC acts as a 100%-reflective mirror. A strain-induced uniform fibre Bragger grating (FBG) which functions as a partial-reflecting mirror is implemented in the linear cavity. By applying axial strain onto the TFBG, a continuously tunable lasing output can be realized. The wavelength tuning range covers approximately 7.00nm in C band (from 1543.6161 to 1550.3307nm). The side mode suppression ratio (SMSR) is better than 50 dB, and the 3 dB bandwidth of the laser is less than 0.01 nm. Moreover, an array waveguide grating (AWG) is inserted into the cavity for wavelength preselecting, and a 50 km transmission experiment was performed using our TEDFL at a 10Gb/s modulation rate

  4. Linear and nonlinear resonance features of an erbium-doped fibre ...

    Indian Academy of Sciences (India)

    2014-07-01

    Jul 1, 2014 ... Abstract. The continuous-wave output of a single-mode erbium-doped fibre ring laser when sub- jected to cavity-loss modulation is found to exhibit linear as well as nonlinear resonances. At sufficiently low driving amplitude, the system resembles a linear damped oscillator. At higher amplitudes, the ...

  5. Implementation of Lean System on Erbium Doped Fibre Amplifier Manufacturing Process to Reduce Production Time

    Science.gov (United States)

    Maneechote, T.; Luangpaiboon, P.

    2010-10-01

    A manufacturing process of erbium doped fibre amplifiers is complicated. It needs to meet the customers' requirements under a present economic status that products need to be shipped to customers as soon as possible after purchasing orders. This research aims to study and improve processes and production lines of erbium doped fibre amplifiers using lean manufacturing systems via an application of computer simulation. Three scenarios of lean tooled box systems are selected via the expert system. Firstly, the production schedule based on shipment date is combined with a first in first out control system. The second scenario focuses on a designed flow process plant layout. Finally, the previous flow process plant layout combines with production schedule based on shipment date including the first in first out control systems. The computer simulation with the limited data via an expected value is used to observe the performance of all scenarios. The most preferable resulted lean tooled box systems from a computer simulation are selected to implement in the real process of a production of erbium doped fibre amplifiers. A comparison is carried out to determine the actual performance measures via an analysis of variance of the response or the production time per unit achieved in each scenario. The goodness of an adequacy of the linear statistical model via experimental errors or residuals is also performed to check the normality, constant variance and independence of the residuals. The results show that a hybrid scenario of lean manufacturing system with the first in first out control and flow process plant lay out statistically leads to better performance in terms of the mean and variance of production times.

  6. Stable Dual-Wavelength Fibre Laser with Bragg Gratings Fabricated in a Polarization-Maintaining Erbium-Doped Fibre

    International Nuclear Information System (INIS)

    Lin, Wang; Feng-Ping, Yan; Xiang-Qiao, Mao; Shui-Sheng, Jian

    2008-01-01

    A new polarization-independent dual-wavelength fibre laser by fabricating a uniform FBG and a chirped FBG in a polarization-maintaining erbium-doped fibre (PM-EDF) is proposed and demonstrated. The wavelength spacing is 0.18nm and the optical signal-to-noise ratio is greater than 50dB with pump power of 246mW. Chirped FBG is used to make the reflectivity wavelengths of two PM-FBGs match easier. Since both EDF and FBGs are polarization-maintaining without splices and the two wavelengths are polarization-independent, the maximum amplitude variation and wavelength shifts for both lasing wavelength with 3-min intervals over a period of six hours are less than 0.2 dB and 0.005 nm, respectively, which shows stable dual-wavelength output

  7. Wideband and flat-gain amplifier based on high concentration erbium-doped fibres in parallel double-pass configuration

    International Nuclear Information System (INIS)

    Hamida, B A; Cheng, X S; Harun, S W; Naji, A W; Arof, H; Al-Khateeb, W; Khan, S; Ahmad, H

    2012-01-01

    A wideband and flat gain erbium-doped fibre amplifier (EDFA) is demonstrated using a hybrid gain medium of a zirconiabased erbium-doped fibre (Zr-EDF) and a high concentration erbium-doped fibre (EDF). The amplifier has two stages comprising a 2-m-long ZEDF and 9-m-long EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region.

  8. Integrated cladding-pumped multicore few-mode erbium-doped fibre amplifier for space-division-multiplexed communications

    Science.gov (United States)

    Chen, H.; Jin, C.; Huang, B.; Fontaine, N. K.; Ryf, R.; Shang, K.; Grégoire, N.; Morency, S.; Essiambre, R.-J.; Li, G.; Messaddeq, Y.; Larochelle, S.

    2016-08-01

    Space-division multiplexing (SDM), whereby multiple spatial channels in multimode and multicore optical fibres are used to increase the total transmission capacity per fibre, is being investigated to avert a data capacity crunch and reduce the cost per transmitted bit. With the number of channels employed in SDM transmission experiments continuing to rise, there is a requirement for integrated SDM components that are scalable. Here, we demonstrate a cladding-pumped SDM erbium-doped fibre amplifier (EDFA) that consists of six uncoupled multimode erbium-doped cores. Each core supports three spatial modes, which enables the EDFA to amplify a total of 18 spatial channels (six cores × three modes) simultaneously with a single pump diode and a complexity similar to a single-mode EDFA. The amplifier delivers >20 dBm total output power per core and <7 dB noise figure over the C-band. This cladding-pumped EDFA enables combined space-division and wavelength-division multiplexed transmission over multiple multimode fibre spans.

  9. Erbium-doped twin-core fibre narrow-band filter for fibre lasers

    Czech Academy of Sciences Publication Activity Database

    Peterka, Pavel; Kaňka, Jiří

    2001-01-01

    Roč. 33, 4/5 (2001), s. 571-581 ISSN 0306-8919. [Optical Waveguide Theory and Numerical Modelling /8./. Prague, 26.05.2000-27.05.2000] R&D Projects: GA ČR GA102/99/M057; GA ČR GA102/99/0393; GA AV ČR IAC2067902 Grant - others:EU COST(XE) OC 265.10 Institutional research plan: CEZ:AV0Z2067918 Keywords : optical fibre lasers * optical fibre filters * optical fibre couplers Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.706, year: 2001 http://www.ufe.cz/~peterka/opera/OQE_Peterka01_fulltext.pdf

  10. Progress on erbium-doped waveguide components

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Berendt, Martin Ole; Broeng, Jes

    1997-01-01

    The recent development in erbium-doped fiber amplifiers, and fiber lasers is reviewed. Also the latest results on planar erbium-doped waveguide amplifiers and high erbium concentration characterisation methods are presented...

  11. Erbium Doped Fiber Optic Gravimeter

    International Nuclear Information System (INIS)

    Pérez-Sánchez, G G; Pérez-Torres, J R; Flores-Bravo, J A; Álvarez-Chávez, J A; Martínez-Piñón, F

    2017-01-01

    Gravimeters are devices that can be used in a wide range of applications, such as mining, seismology, geodesy, archeology, geophysics and many others. These devices have great sensibility, which makes them susceptible to external vibrations like electromagnetic waves. There are several technologies regarding gravimeters that are of use in industrial metrology. Optical fiber is immune to electromagnetic interference, and together with long period gratings can form high sensibility sensors of small size, offering advantages over other systems with different technologies. This paper shows the development of an optical fiber gravimeter doped with Erbium that was characterized optically for loads going from 1 to 10 kg in a bandwidth between 1590nm to 1960nm, displaying a weight linear response against power. Later on this paper, the experimental results show that the previous described behavior can be modeled as characteristic function of the sensor. (paper)

  12. Luminescence of porous silicon doped by erbium

    International Nuclear Information System (INIS)

    Bondarenko, V.P.; Vorozov, N.N.; Dolgij, L.N.; Dorofeev, A.M.; Kazyuchits, N.M.; Leshok, A.A.; Troyanova, G.N.

    1996-01-01

    The possibility of the 1.54 μm intensive luminescence in the silicon dense porous layers, doped by erbium, with various structures is shown. Low-porous materials of both porous type on the p-type silicon and porous silicon with wood-like structure on the n + type silicon may be used for formation of light-emitting structures

  13. Erbium doped stain etched porous silicon

    International Nuclear Information System (INIS)

    Gonzalez-Diaz, B.; Diaz-Herrera, B.; Guerrero-Lemus, R.; Mendez-Ramos, J.; Rodriguez, V.D.; Hernandez-Rodriguez, C.; Martinez-Duart, J.M.

    2008-01-01

    In this work a simple erbium doping process applied to stain etched porous silicon layers (PSLs) is proposed. This doping process has been developed for application in porous silicon solar cells, where conventional erbium doping processes are not affordable because of the high processing cost and technical difficulties. The PSLs were formed by immersion in a HF/HNO 3 solution to properly adjust the porosity and pore thickness to an optimal doping of the porous structure. After the formation of the porous structure, the PSLs were analyzed by means of nitrogen BET (Brunauer, Emmett and Teller) area measurements and scanning electron microscopy. Subsequently, the PSLs were immersed in a saturated erbium nitrate solution in order to cover the porous surface. Then, the samples were subjected to a thermal process to activate the Er 3+ ions. Different temperatures and annealing times were used in this process. The photoluminescence of the PSLs was evaluated before and after the doping processes and the composition was analyzed by Fourier transform IR spectroscopy

  14. Noise in distributed erbium-doped fibers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Povlsen, Jørn Hedegaard; Bjarklev, Anders Overgaard

    1993-01-01

    Theoretical limits in noise figure for a long-haul transmission line based on lumped amplification are contrasted with distributed amplification. The latter results in a reduction of approximately 60% of the required number of pump power stations. The distributed optical amplification is provided...... by an erbium-doped fiber and comparisons of aluminum and germanium as codopant materials are shown. The pump power consumption and noise figure are analyzed with respect to the background loss...

  15. ytterbium- & erbium-doped silica for planar waveguide lasers & amplifiers

    DEFF Research Database (Denmark)

    Dyndgaard, Morten Glarborg

    2001-01-01

    The purpose of this work was to demonstrate ytterbium doped planar components and investigate the possibilities of making erbium/ytterbium codoped planar waveguides in germano-silica glass. Furthermore, tools for modelling lasers and erbium/ytterbium doped amplifiers. The planar waveguides were...

  16. Comparison on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fibre lasers

    Science.gov (United States)

    Yang, Chun-Yu; Lin, Yung-Hsiang; Wu, Chung-Lun; Cheng, Chih-Hsien; Tsai, Din-Ping; Lin, Gong-Ru

    2018-06-01

    Comparisons on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fiber lasers (EDFLs) are performed. As opposed to the graphite nano-particles obtained by physically triturating the graphite foil, the tri-layer graphene nano-sheets is obtained by electrochemically exfoliating the graphite foil. To precisely control the size dispersion and the layer number of the exfoliated graphene nano-sheet, both the bias of electrochemical exfoliation and the speed of centrifugation are optimized. Under a threshold exfoliation bias of 3 volts and a centrifugation at 1000 rpm, graphene nano-sheets with an average diameter of 100  ±  40 nm can be obtained. The graphene nano-sheets with an area density of 15 #/µm2 are directly imprinted onto the end-face of a single-mode fiber made patchcord connector inside the EDFL cavity. Such electrochemically exfoliated graphene nano-sheets show comparable saturable absorption with standard single-graphene and perform the self-amplitude modulation better than physically triturated graphite nano-particles. The linear transmittance and modulation depth of the inserted graphene nano-sheets are 92.5% and 53%, respectively. Under the operation with a power gain of 21.5 dB, the EDFL can be passively mode-locked to deliver a pulsewidth of 454.5 fs with a spectral linewidth of 5.6 nm. The time-bandwidth product of 0.31 is close to the transform limit. The Kelly sideband frequency spacing of 1.34 THz is used to calculate the chirp coefficient as  ‑0.0015.

  17. Long distance transmission through distributed erbium-doped fibers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Povlsen, Jørn Hedegaard; Bjarklev, Anders Overgaard

    1993-01-01

    High bit rate, all-optical long-distance transmission could be created through the combined use of loss-compensating gain in erbium-doped fibers and solitons. A detailed analysis of the distributed erbium-doped fiber, including the spectral-gain dependency, is combined with an optimum design...... of the transmission fiber and general bit-error-rate calculations. Changes in wavenumber, group velocity, and fiber dispersion due to erbium doping in a single-mode fiber are evaluated, and a reduction in bit-error rates due to the erbium spectral-gain profile is shown. Transmission through distributed erbium......-doped fiber with 100-km separation between each pump-power station is shown, with a total bit-rate distance product of 55 Gb/s · Mm...

  18. Detailed design analysis of erbium-doped fiber amplifiers

    DEFF Research Database (Denmark)

    Pedersen, Bo; Bjarklev, Anders Overgaard; Lumholt, Ole

    1991-01-01

    When pumping the erbium-doped fiber amplifier at 0.98 and 1.48 mu m, the optimum cutoff wavelength for step profiles with arbitrary numerical aperture is shown to be 0.80 and 0.90 mu m, respectively. The use of a confined erbium profile can improve the gain coefficient up to 45%. The index raising...

  19. Optical properties of erbium-doped porous silicon waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Najar, A. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B P. 80518, 22305 Lannion Cedex (France); Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia); Charrier, J. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B P. 80518, 22305 Lannion Cedex (France)]. E-mail: joel.charier@univ-rennes1.fr; Ajlani, H. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia); Lorrain, N. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B P. 80518, 22305 Lannion Cedex (France); Elhouichet, H. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia); Oueslati, M. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia); Haji, L. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B P. 80518, 22305 Lannion Cedex (France)

    2006-12-15

    Planar and buried channel porous silicon waveguides (WG) were prepared from p{sup +}-type silicon substrate by a two-step anodization process. Erbium ions were incorporated into pores of the porous silicon layers by an electrochemical method using ErCl{sub 3}-saturated solution. Erbium concentration of around 10{sup 20} at/cm{sup 3} was determined by energy-dispersive X-ray analysis performed on SEM cross-section. The luminescence properties of erbium ions in the IR range were determined and a luminescence time decay of 420 {mu}s was measured. Optical losses were studied on these WG. The increased losses after doping were discussed.

  20. Erbium-doped integrated waveguide amplifiers and lasers

    NARCIS (Netherlands)

    Bradley, J.; Pollnau, Markus

    Erbium-doped fiber devices have been extraordinarily successful due to their broad optical gain around 1.5–1.6 μm. Er-doped fiber amplifiers enable efficient, stable amplification of high-speed, wavelength-division-multiplexed signals, thus continue to dominate as part of the backbone of longhaul

  1. Spectroscopic properties of Pr -doped erbium oxalate crystals

    Indian Academy of Sciences (India)

    Spectroscopic properties of praseodymium ions-doped erbium oxalate ... solution with specific gravity 1.04 g/cm3 was mixed homogeneously with 0.5 M oxalic ... of concentrated nitric acid were transferred carefully and gently through the wall ...

  2. Polyurethane doped with low-concentration erbium

    NARCIS (Netherlands)

    Ciobanu, C.; Stoica, E.; Cascaval, C.N.; Rosu, D.; Rosu, L.; State, M.; Emandi, A.; Nemes, I.; Petrescu, F.

    2007-01-01

    ABSTRACT: Polyurethane (PU) with lactate structures inits conformation can be used as a biological and biodegradablepolymer. Polyurethane lactate (PUL) was dopedwith small quantities of an erbium (Er3þ) complex, whichhindered the N¼N group. 2,20-Dihydroxyazobenzene wasused as a ligand for the Er3þ

  3. Rate equation modelling of erbium luminescence dynamics in erbium-doped silicon-rich-silicon-oxide

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Miraj, E-mail: m.shah@ee.ucl.ac.uk [Department of Electronic and Electrical Engineering, UCL, Torrington Place, London WC1E 7JE (United Kingdom); Wojdak, Maciej; Kenyon, Anthony J. [Department of Electronic and Electrical Engineering, UCL, Torrington Place, London WC1E 7JE (United Kingdom); Halsall, Matthew P.; Li, Hang; Crowe, Iain F. [Photon Science Institute and School of Electrical and Electronic Engineering, University of Manchester, Sackville St Building, Manchester M13 9PL (United Kingdom)

    2012-12-15

    Erbium doped silicon-rich silica offers broad band and very efficient excitation of erbium photoluminescence (PL) due to a sensitization effect attributed to silicon nanocrystals (Si-nc), which grow during thermal treatment. PL decay lifetime measurements of sensitised Er{sup 3+} ions are usually reported to be stretched or multi exponential, very different to those that are directly excited, which usually show a single exponential decay component. In this paper, we report on SiO{sub 2} thin films doped with Si-nc's and erbium. Time resolved PL measurements reveal two distinct 1.54 {mu}m Er decay components; a fast microsecond component, and a relatively long lifetime component (10 ms). We also study the structural properties of these samples through TEM measurements, and reveal the formation of Er clusters. We propose that these Er clusters are responsible for the fast {mu}s decay component, and we develop rate equation models that reproduce the experimental transient observations, and can explain some of the reported transient behaviour in previously published literature.

  4. Erbium-doped fiber lasers as deep-sea hydrophones

    International Nuclear Information System (INIS)

    Bagnoli, P.E.; Beverini, N.; Bouhadef, B.; Castorina, E.; Falchini, E.; Falciai, R.; Flaminio, V.; Maccioni, E.; Morganti, M.; Sorrentino, F.; Stefani, F.; Trono, C.

    2006-01-01

    The present work describes the development of a hydrophone prototype for deep-sea acoustic detection. The base-sensitive element is a single-mode erbium-doped fiber laser. The high sensitivity of these sensors makes them particularly suitable for a wide range of deep-sea acoustic applications, including geological and marine mammals surveys and above all as acoustic detectors in under-water telescopes for high-energy neutrinos

  5. NEW ERBIUM DOPED ANTIMONY GLASSES FOR LASER AND GLASS AMPLIFICATION

    Directory of Open Access Journals (Sweden)

    B. Tioua

    2015-07-01

    Full Text Available Because of the special spectroscopic properties of the rare earth ions, rare earth doped glasses are widely used in bulk and fiber lasers or amplifiers. The modelling of lasers and searching for new laser transitions require a precise knowledge of the spectroscopic properties of rare earth ions in different host glasses. In this poster will offer new doped erbium glasses synthesized in silicate crucibles were obtained in the combination Sb2O3-WO3-Na2O. Several properties are measured and correlated with glass compositions. The absorption spectral studies have been performed for erbium doped glasses. The intensities of various absorption bands of the doped glasses are measured and the Judd-Ofelt parameters have been computed. From the theory of Judd-Ofelt, various radiative properties, such as transition probability, branching ratio and radiative life time for various emission levels of these doped glasses have been determined and reported. These results confirm the ability of antimony glasses for glass amplification.

  6. High gain L-band erbium-doped fiber amplifier with two-stage ...

    Indian Academy of Sciences (India)

    stage erbium-doped fiber amplifier; amplified spontaneous emission. Abstract. An experiment on gain enhancement in the long wavelength band erbium-doped fiber amplifier (L-band EDFA) is demonstrated using dual forward pumping scheme ...

  7. Few-mode erbium-doped fiber amplifier with photonic lantern for pump spatial mode control

    NARCIS (Netherlands)

    Lopez-Galmiche, G.; Eznaveh, Z. Sanjabi; Antonio-Lopez, J.E.; Benitez, A. M. Velazquez; Rodriguez-Asomoza, Jorge; Mondragon, J. J. Sanchez; Gonnet, C.; Sillard, P.; Li, G.; Schülzgen, A.; Okonkwo, C.M.; Amezcua Correa, R.

    2016-01-01

    We demonstrate a few-mode erbium-doped fiber amplifier employing a mode-selective photonic lantern for controlling the modal content of the pump light. Amplification of six spatial modes in a 5 m long erbium-doped fiber to x223C;6.2x2009;x2009;dBm average power is obtained while maintaining high

  8. Optical properties of ion beam modified waveguide materials doped with erbium and silver

    NARCIS (Netherlands)

    Strohhöfer, C. (Christof)

    2001-01-01

    In the first part of this thesis we investigate codoping of erbium-doped waveguide materials with different ions in order to increase the efficiency of erbium-doped optical amplifiers. Codoping with ytterbium can overcome the limitations due to the small absorption cross section of Er3+ in Al2O3 at

  9. Effect of the doped fibre length on soliton pulses of a bidirectional mode-locked fibre laser

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, H; Alwi Kutty, N A; Zulkifli, M Z; Harun, S W [Photonics Research Center (Department of Physics), University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-08-31

    A passively bidirectional mode-locked fibre laser is demonstrated using a highly concentrated erbium-doped fibre (EDF) as a gain medium. To accomplish mode-locked operation in a short cavity, use is made of carbon nanotubes (CNTs) as a saturable absorber. Soliton pulses are obtained at a wavelength of 1560 nm with a repetition rate ranging from 43.92 MHz to 46.97 MHz and pulse width stretching from 0.56 ps to 0.41 ps as the EDF length is reduced from 60 cm to 30 cm. (lasers)

  10. Optimum position of isolators within erbium-doped fibers

    DEFF Research Database (Denmark)

    Lumholt, Ole; Schüsler, Kim; Bjarklev, Anders Overgaard

    1992-01-01

    An isolator is used as an amplified spontaneous emission suppressing component within an erbium-doped fiber. The optimum isolator placement is both experimentally and theoretically determined and found to be slightly dependent upon pump power. Improvements of 4 dB in gain and 2 dB in noise figure...... are measured for the optimum isolator location at 25% of the fiber length when the fiber is pumped with 60 mW of pump power at 1.48 μm...

  11. Characterization of an erbium doped fiber amplifier starting from its experimental parameters

    International Nuclear Information System (INIS)

    Bello J, M.; Kuzin, E.A.; Ibarra E, B.; Tellez G, R.

    2007-01-01

    In this paper we describe a method to characterize the gain of an erbium-doped fiber amplifier (EDFA) through the numerical simulation of the signal beam along the amplifier. The simulation is based on a model constituted by the propagation and rate equations for an erbium-doped fiber. The manipulation of these equations allows us to regroup the parameters present in an EDFA, which we have named the A, B, C, D parameters, and they can be obtained experimentally from an erbium-doped fiber. Experimental results show that the measurement of these parameters allow us to estimate with very good correspondence the amplifier gain. (Author)

  12. Serial topology of wide-band erbium-doped fiber amplifier for WDM applications

    Czech Academy of Sciences Publication Activity Database

    Karásek, Miroslav; Menif, M.

    2001-01-01

    Roč. 13, č. 9 (2001), s. 939-941 ISSN 1041-1135 R&D Projects: GA ČR GA102/99/0393 Institutional research plan: CEZ:AV0Z2067918 Keywords : erbium * wavelength division multiplexing * optical fibre amplifiers * optical fibre communication Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.004, year: 2001

  13. Optical bistability of optical fiber ring doped by Erbium and quantum dots

    International Nuclear Information System (INIS)

    Safari, S.; Tofighi, S.; Bahrampour, A.; Sajad, B.; Shahshahani, F.

    2012-01-01

    In this paper, theoretical analysis of the steady state behavior of the optical bistability in an optical fiber ring doped by Erbium and quantum dots is presented. The up and down switching power is calculated and the dependence of the switching power on different fiber ring parameters is investigated. The switching power for this type of optical bistability device is obtained much lower than the fiber ring which its half length is doped by Erbium ion.

  14. Harmonic Dark Pulse Emission in Erbium-Doped Fiber Laser

    International Nuclear Information System (INIS)

    Zian, Cheak Tiu; Arman, Zarei; Sin, Jin Tan; Harith, Ahmad; Sulaiman, Wadi Harun

    2015-01-01

    A harmonic dark pulse generation in an erbium-doped fiber laser is demonstrated based on a figure-of-eight configuration. It is found that the harmonic dark pulse can be shifted from the fundamental to the 5"t"h order harmonic by increasing the pump power with an appropriate polarization controller orientation. The fundamental repetition rate of 20 kHz is obtained at the pump power of 29 mW. The highest pulse energy of 42.6 nJ is obtained at the fundamental repetition rate. The operating frequency of the dark pulse trains shifts to 2"n"d, 3"r"d, 4"t"h and 5"t"h harmonic as the pump powers are increased to 34 mW, 50 mW, 59 mW and 137 mW, respectively. (paper)

  15. Fibre Tip Sensors for Localised Temperature Sensing Based on Rare Earth-Doped Glass Coatings

    Directory of Open Access Journals (Sweden)

    Erik P. Schartner

    2014-11-01

    Full Text Available We report the development of a point temperature sensor, based on monitoring upconversion emission from erbium:ytterbium-doped tellurite coatings on the tips of optical fibres. The dip coating technique allows multiple sensors to be fabricated simultaneously, while confining the temperature-sensitive region to a localised region on the end-face of the fibre. The strong response of the rare earth ions to changing temperature allows a resolution of 0.1–0.3 °C to be recorded over the biologically relevant range of temperatures from 23–39 °C.

  16. Multi-wavelength Brillouin Raman erbium-doped fiber laser generation in a linear cavity

    International Nuclear Information System (INIS)

    Shirazi, M R; Harun, S W; Ahmad, H

    2014-01-01

    A multi-wavelength Brillouin Raman erbium-doped fiber laser is proposed and demonstrated. The setup uses a 7.7 km dispersion compensating fiber simultaneously as the Brillouin and Raman nonlinear gain media and operates in conjunction with a 3 m erbium-doped fiber as the linear gain medium. At a Brillouin pump (BP) wavelength of 1530 nm, where Raman and erbium gains overlap each other, 34 Brillouin Stokes lines having line spacing of 0.075 nm are created by using a Raman pump power of only 24.1 dBm, an erbium pump power of about 22.1 dBm, and a BP power of 6.5 dBm in the proposed linear cavity. The system is highly efficient and is able to generate many comparable peak-power lines at a low pump power. (paper)

  17. Enhanced light emission in photonic crystal nanocavities with Erbium-doped silicon nanocrystals

    International Nuclear Information System (INIS)

    Makarova, Maria; Sih, Vanessa; Vuckovic, Jelena; Warga, Joe; Li Rui; Dal Negro, Luca

    2008-01-01

    Photonic crystal nanocavities are fabricated in silicon membranes covered by thermally annealed silicon-rich nitride films with Erbium-doped silicon nanocrystals. Silicon nitride films were deposited by sputtering on top of silicon on insulator wafers. The nanocavities were carefully designed in order to enhance emission from the nanocrystal sensitized Erbium at the 1540 nm wavelength. Experimentally measured quality factors of ∼6000 were found to be consistent theoretical predictions. The Purcell factor of 1.4 was estimated from the observed 20-fold enhancement of Erbium luminescence

  18. The infra-red photoresponse of erbium-doped silicon nanocrystals

    International Nuclear Information System (INIS)

    Kenyon, A.J.; Bhamber, S.S.; Pitt, C.W.

    2003-01-01

    We have exploited the interaction between erbium ions and silicon nanoclusters to probe the photoresponse of erbium-doped silicon nanocrystals in the spectral region around 1.5 μm. We have produced an MOS device in which the oxide layer has been implanted with both erbium and silicon and annealed to produce silicon nanocrystals. Upon illumination with a 1480 nm laser diode, interaction between the nanocrystals and the rare-earth ions results in a modification of the conductivity of the oxide that enables a current to flow when a voltage is applied across the oxide layer

  19. Unconventional cells of TiO2 doped with erbium

    International Nuclear Information System (INIS)

    Ribeiro, P.C.; Campos, R.D.; Oliveira, A.S.; Wellen, R.; Diniz, V.C.S.; Costa, A.C.F.M. da

    2016-01-01

    The technology used in TiO_2 solar cells is in constant improvement, new configurations have been developed, aiming practicality and leading to efficiency increase of photovoltaic devices. This paper proposes a new technology for the production of solar cells in order to investigate a better utilization of solar spectrum of TiO2 doped with erbium (Er"3"+), proven by energetic conversion. The Ti_0_,_9Er_0_,_1O2 system was obtained by Pechini method. Nanoparticles have a crystallite size 65.30 nm and surface area 118.48 m"2/g. These characteristics are essential for the formation of the film to be deposited on the conductive glass substrate constituting the cell's photoelectrode. The other side of the cell is the platinum counter electrode. The cell will have the faces sealed by a thermoplastic and, finally the electrolyte will be inserted, then they will be electrically evaluated through energy efficiency and confronted with the literature data base. (author)

  20. Precipitate coarsening and self organization in erbium-doped silica

    DEFF Research Database (Denmark)

    Sckerl, Mads W.; Guldberg-Kjær, Søren Andreas; Poulsen, Mogens Rysholt

    1999-01-01

    The influence of heat treatment at and above 1100 degrees C on thin erbium-rich silica layers embedded in silica has been studied experimentally by secondary ion-mass spectrometry and cross-sectional transmission electron microscopy. Redistribution of erbium atoms is observed at these temperature...

  1. Synthesis and thermoluminescent characterization of lithium niobate doped with erbium

    International Nuclear Information System (INIS)

    Landavazo, M.; Brown, F.; Cubillas, F.; Munoz, I.; Cruz Z, E.

    2015-10-01

    Full text: Lithium niobate (Nl) is a synthetic dielectric and is mainly used in optical devices. There are reports on the thermoluminescent property of Nl monocrystals doped with rare earths and excited with X and gamma rays. In this study the Nl was synthesized and doped with erbium (Er) at concentrations of 1, 2 and 4 % mol and was characterized by its Tl property. The synthesis was realized by solid state reaction at 1000 degrees C for 22 hours and the formation of Nl:Er was confirmed by X-ray diffraction, scanning electron microscopy and EDS analysis, finding a new phase (ErNbO 4 ). Was studied the dose-response gamma in a range of 1-1000 Gy, the material showed linear behavior of 1-600 Gy. The brightness curves have maxima at 185 and 285 degrees C to 1% in 183 and 301 degrees C for 2%, respectively. While for the concentration of 4% a maximum in 177 degrees C accompanied by a smaller peak at higher temperature of the glow curve was observed. The Tl response of Nl:Er 4% to 450 Gy was increased 271 times compared to pure Nl. The reproducibility of the Tl signal at ten cycles of irradiation-reading, present a standard deviation of 5%. In Nl:Er 1% Tl signal fades in 21.3% after 24 hours, while in 2 and 4% an unusual fading occurs. The Tl characteristics of Nl:Er synthesized material is of interest to gamma radiation dosimetry of high doses. (Author)

  2. Radiation effects on erbium doped optical fibers: on the influence of the fiber composition

    International Nuclear Information System (INIS)

    Tortech, B.

    2008-01-01

    We have studied the erbium-doped fibers (EDF) sensitivity under irradiation and the induced defects. The first chapter presents the state of the art for the EDF under irradiation as well as some radiation generated silica defects. The second chapter details the radiations used in this thesis and the experimental set-ups implemented for the characterization of the fiber responses under irradiation and the radiation induced defects. In the third chapter, we present the response of several erbium-doped fibers irradiated with γ-rays, protons and pulsed X-rays. The erbium doped fibers have higher radiation induced sensitivity than the Telecom fibers (SMF28) or than erbium-doped fibers containing little aluminum. The aluminum presence in the EDF core composition is mainly responsible for the fiber performance degradation. Whatever the irradiation types, the radiation generated defects are related to the host matrix. Our studies also display that the erbium ions are only affected by the interaction with the created defects. The fourth chapter deals with the EDF under UV exposure and shows that the UV rays lead to the same effects than the gamma rays. The last chapter of this thesis presents the study of optical fiber amplifiers under γ irradiation. (author)

  3. Optical bistability in erbium-doped yttrium aluminum garnet crystal combined with a laser diode.

    Science.gov (United States)

    Maeda, Y

    1994-01-10

    Optical bistability was observed in a simple structure of an injection laser diode combined with an erbium-doped yttrium aluminum garnet crystal. Since a hysteresis characteristic exists in the relationship between the wavelength and the injection current of a laser diode, an optical memory function capable of holding the output status is confirmed. In addition, an optical signal inversion was caused by the decrease of transmission of the erbium-doped yttrium aluminum garnet crystal against the red shift (principally mode hopping) of the laser diode. It is suggested that the switching time of this phenomenon is the time necessary for a mode hopping by current injection.

  4. Fast and slow light property improvement in erbium-doped amplifier

    Science.gov (United States)

    Peng, P. C.; Wu, F. K.; Kao, W. C.; Chen, J.; Lin, C. T.; Chi, S.

    2013-01-01

    This work experimentally demonstrates improvement of the fast light property in erbium-doped amplifiers at room temperature. The difference between the signal power and the pump power associated with bending loss is used to control the signal power at the different positions of the erbium-doped fiber (EDF) to improve the fast light property. Periodic bending of the EDF increases the time advance of the probe signal by over 288%. Additionally, this concept also could improve the fast light property using coherent population oscillations in semiconductor optical amplifiers.

  5. Generation and characterization of erbium-Raman noise-like pulses from a figure-eight fibre laser

    International Nuclear Information System (INIS)

    Santiago-Hernandez, H; Pottiez, O; Paez-Aguirre, R; Ibarra-Villalon, H E; Tenorio-Torres, A; Duran-Sanchez, M; Ibarra-Escamilla, B; Kuzin, E A; Hernandez-Garcia, J C

    2015-01-01

    We report an experimental study of the noise-like pulses generated by a ∼300 m long passively mode-locked erbium-doped figure-eight fibre laser. Non-self-starting mode locking yields the formation of ns scale bunches of sub-ps pulses. Depending on birefringence adjustments, noise-like pulses with a variety of temporal profiles and optical spectra are obtained. In particular, for some adjustments the Raman-enhanced spectrum reaches a 10 dB bandwidth of ∼130 nm. For the first time to our knowledge, we extract information on the inner structure of the noise-like pulses, using a birefringent Sagnac interferometer as a spectral filter and a nonlinear optical loop mirror as an intensity filter. In particular we show that the different spectral components of the bunch are homogeneously distributed within the temporal envelope of the bunch, whereas the amplitude and/or the density of the sub-pulses present substantial variations along the envelope. In some cases, the analysis reveals the existence of an intermediate level of organization in the structure of the noise-like pulse, between the ns bunch and the sub-ps inner pulses, suggesting that these objects may be even more complex than previously recognized. (paper)

  6. Modelling of high-power diode-pumped erbium 3-µm fibre lasers

    NARCIS (Netherlands)

    Jackson, S.D.; King, T.A.; Pollnau, Markus

    2000-01-01

    We present theoretical calculations that relate to the cw operation of a high-power Er3+,Pr3+:ZBLAN double-clad fibre laser. Using the measured energy-transfer, energy-transfer-upconversion and cross-relaxation parameters relevant to Er3+-doped and Er3+,Pr3+-codoped ZBLAN, we compare the theoretical

  7. Effects of ion pairs on the dynamics of erbium doped fiber laser in the inhomogeneous model

    International Nuclear Information System (INIS)

    Keyvaninia, Sh.; Karvar, M.; Bahrampour, A.

    2006-01-01

    In a high concentration erbium doped fiber, the erbium ions are so closed together that the ion pairs and clusters are formed. In such fiber amplifiers, the ion pairs and clusters acting as a saturable absorber are distributed along the fiber laser. The inhomogeneous rate equations for the laser modes in a high-concentration EDFA are written. The governing equations are an uncountable system of partial differential equations. For the first time we introduced an approximation method that the system of partial differential equations is converted to a finite system of ordinary differential equations. The effects of ion pairs concentration on erbium doped fiber are analyzed that is in good agreement whit the experimental result.

  8. Stability of a 500 km erbium-doped fiber amplifier cascade

    DEFF Research Database (Denmark)

    Lumholt, Ole; Bjarklev, Anders Overgaard; Povlsen, Jørn Hedegaard

    1992-01-01

    The stability of a cascade system of erbium-doped fiber amplifiers, due to pump and signal power variations, has been examined by use of a very accurate model. Even with an automatic gain control loop included, a fallout of a pump laser in the first inline amplifier is shown to produce a more than...

  9. Radiation hardening commercial off-the-shelf erbium doped fibers by optimal photo-annealing source

    Science.gov (United States)

    Peng, Tz-Shiuan; Liu, Ren-Young; Lin, Yen-Chih; Mao, Ming-Hua; Wang, Lon A.

    2017-09-01

    Erbium doped fibers (EDFs) based devices are widely employed in space for optical communication [1], remote sensing [2], and navigation applications, e.g. interferometric fiber optic gyroscope (IFOG). However, the EDF suffers severely radiation induced attenuation (RIA) in radiation environments, e.g. space applications and nuclear reactors [3].

  10. Temperature Sensor Using a Multiwavelength Erbium-Doped Fiber Ring Laser

    Directory of Open Access Journals (Sweden)

    Silvia Diaz

    2017-01-01

    Full Text Available A novel temperature sensor is presented based on a multiwavelength erbium-doped fiber ring laser. The laser is comprised of fiber Bragg grating reflectors as the oscillation wavelength selecting filters. The performance of the temperature sensor in terms of both wavelength and laser output power was investigated, as well as the application of this system for remote temperature measurements.

  11. Saturation of the 2.71 µm laser output in erbium doped ZBLAN fibers

    NARCIS (Netherlands)

    Bedö, S.; Pollnau, Markus; Lüthy, W.; Weber, H.P.

    1995-01-01

    The saturation of the 2.71 μm laser output power has been investigated in an erbium doped ZBLAN single-mode fiber with an Er3+ concentration of 5000 ppm mol. The bleaching of the ground state, the absorption coefficient at the pump wavelength and the fluorescence intensities over a wide wavelength

  12. Optimization of E r-density profile for efficient pumping and high signal gain in Erbium-doped fiber amplifiers

    International Nuclear Information System (INIS)

    Arzi, E.; Hassani, A.; Esmaili Seraji, F.

    2000-01-01

    Recently, the Erbium-Doped Fiber Amplifier has been shown to have a great potentiality in Fiber-Optics Communication. A model is suggested for calculating the E r-density profile, using the propagation and rate equations of a homogeneous two-level laser medium in Erbium-Doped Fiber Amplifier, such that efficient pumping and high signal gain is achieved for different fiber waveguide structure. The result of this numerical calculation shows that the gain, compared with the gain of the existing Erbium-Doped Fiber Amplifier, is higher by a factor of 3.5. This model is applicable in all active waveguides and any other dopant as well

  13. Optical study of Erbium-doped-porous silicon based planar waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Najar, A. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B.P. 80518, 22305 Lannion Cedex (France) and Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia)]. E-mail: najar.adel@laposte.net; Ajlani, H. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia); Charrier, J. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B.P. 80518, 22305 Lannion Cedex (France); Lorrain, N. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B.P. 80518, 22305 Lannion Cedex (France); Haesaert, S. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B.P. 80518, 22305 Lannion Cedex (France); Oueslati, M. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 ElManar, Tunis (Tunisia); Haji, L. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, B.P. 80518, 22305 Lannion Cedex (France)

    2007-06-15

    Planar waveguides were formed from porous silicon layers obtained on P{sup +} substrates. These waveguides were then doped by erbium using an electrochemical method. Erbium concentration in the range 2.2-2.5 at% was determined by energy dispersive X-ray (EDX) analysis performed on SEM cross sections. The refractive index of layers was studied before and after doping and thermal treatments. The photoluminescence of Er{sup 3+} ions in the IR range and the decay curve of the 1.53 {mu}m emission peak were studied as a function of the excitation power. The value of excited Er density was equal to 0.07%. Optical loss contributions were analyzed on these waveguides and the losses were equal to 1.1 dB/cm at 1.55 {mu}m after doping.

  14. Flat Ge-doped optical fibres for food irradiation dosimetry

    International Nuclear Information System (INIS)

    Noor, N. Mohd; Jusoh, M. A.; Razis, A. F. Abdull; Alawiah, A.; Bradley, D. A.

    2015-01-01

    Exposing food to radiation can improve hygiene quality, germination control, retard sprouting, and enhance physical attributes of the food product. To provide for food safety, radiation dosimetry in irradiated food is required. Herein, fabricated germanium doped (Ge-doped) optical fibres have been used. The fibres have been irradiated using a gamma source irradiator, doses in the range 1 kGy to 10 kGy being delivered. Using Ge-doped optical fibres of variable size, type and dopant concentration, study has been made of linearity, reproducibility, and fading. The thermoluminescence (TL) yield of the fibres were obtained and compared. The fibres exhibit a linear dose response over the investigated range of doses, with mean reproducibility to within 2.69 % to 8.77 %, exceeding the dose range of all commercial dosimeters used in evaluating high doses for the food irradiation industry. TL fading of the Ge-doped flat fibres has been found to be < 13%

  15. Flat Ge-doped optical fibres for food irradiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Noor, N. Mohd; Jusoh, M. A. [Department of Imaging, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Razis, A. F. Abdull [Food Safety Research Centre, Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Laboratory of UPM-MAKNA Cancer Research, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Alawiah, A. [Faculty of Engineering and Technology, Multimedia University, 75450 Malacca (Malaysia); Bradley, D. A. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-04-24

    Exposing food to radiation can improve hygiene quality, germination control, retard sprouting, and enhance physical attributes of the food product. To provide for food safety, radiation dosimetry in irradiated food is required. Herein, fabricated germanium doped (Ge-doped) optical fibres have been used. The fibres have been irradiated using a gamma source irradiator, doses in the range 1 kGy to 10 kGy being delivered. Using Ge-doped optical fibres of variable size, type and dopant concentration, study has been made of linearity, reproducibility, and fading. The thermoluminescence (TL) yield of the fibres were obtained and compared. The fibres exhibit a linear dose response over the investigated range of doses, with mean reproducibility to within 2.69 % to 8.77 %, exceeding the dose range of all commercial dosimeters used in evaluating high doses for the food irradiation industry. TL fading of the Ge-doped flat fibres has been found to be < 13%.

  16. Empirical multichannel power consumption model for erbium-doped fiber amplifiers

    DEFF Research Database (Denmark)

    Saldaña Cercos, Silvia; de Paiva, Getulio E. R.; Argentato, Marcio Colazza

    2015-01-01

    In this paper we report on the first experimental power consumption analysis and model of single and multi-stage booster erbium-doped fiber amplifiers (EDFAs) with automatic gain control (AGC), accounting for channel number dependency. Results show that the amount of channels being amplified simu......-users, it is relevant to study channel number dependent power consumption for devising EDFA power efficient control and design.......In this paper we report on the first experimental power consumption analysis and model of single and multi-stage booster erbium-doped fiber amplifiers (EDFAs) with automatic gain control (AGC), accounting for channel number dependency. Results show that the amount of channels being amplified...... simultaneously contributes significantly, up to 48%, to the total power consumption due to the circuitry used for controlling the EDFA. As the number of simultaneous amplified WDM channels in high capacity long and medium reach transmission links reflects closely traffic patterns generated by end...

  17. Light up conversion effects in Erbium doped CaBi4Ti4O15 ceramics

    International Nuclear Information System (INIS)

    Bokolia, Renuka; Sreenivas, K.

    2013-01-01

    In recent years the rare earth doped bismuth layered structured ferroelectric (BLSF) compositions such as CaBi 4 Ti 4 O 15 , SrBi 4 Ti 4 O 15 and BaBi 4 Ti 4 O 15 ceramics have shown interesting light up-conversion emission effects. The observation of such novel effects has generated a lot of scientific interest, and there is a need to further improve their dielectric, piezoelectric and light up-conversion properties. In the present study, Erbium doped CaBi 4 Ti 4 O 15 (CBT), and SrBi 4 Ti 4 O 15 (SBT) ferroelectric ceramic have been prepared by the conventional solid state reaction method. Formation of single phase material is confirmed by X-Ray Diffraction (XRD), and changes occurring in the lattice parameters with Erbium dopant are analysed. Room temperature dielectric studies and ferroelectric studies will be discussed. (author)

  18. 2-LP mode few-mode fiber amplifier employing ring-core erbium-doped fiber.

    Science.gov (United States)

    Ono, Hirotaka; Hosokawa, Tsukasa; Ichii, Kentaro; Matsuo, Shoichiro; Nasu, Hitoshi; Yamada, Makoto

    2015-10-19

    A fiber amplifier supporting 2 LP modes that employs a ring-core erbium-doped fiber (RC-EDF) is investigated to reduce differential modal gain (DMG). The inner and outer radii of the ring-core of the RC-EDF are clarified for 2-LP mode operation of the amplifier, and are optimized to reduce the DMG. It is shown that using the overlap integral between the erbium-doped core area and the signal power mode distribution is a good way to optimize the inner and outer radii of the ring-core of the RC-EDF and thus minimize the DMG. A fabricated RC-EDF and a constructed 2-LP mode EDFA are described and a small DMG of around 1 dB is realized for LP01, LP11 and LP21 pumping.

  19. Erbium-doped fiber ring resonator for resonant fiber optical gyro applications

    Science.gov (United States)

    Li, Chunming; Zhao, Rui; Tang, Jun; Xia, Meijing; Guo, Huiting; Xie, Chengfeng; Wang, Lei; Liu, Jun

    2018-04-01

    This paper reports a fiber ring resonator with erbium-doped fiber (EDF) for resonant fiber optical gyro (RFOG). To analyze compensation mechanism of the EDF on resonator, a mathematical model of the erbium-doped fiber ring resonator (EDFRR) is established based on Jones matrix to be followed by the design and fabrication of a tunable EDFRR. The performances of the fabricated EDFRR were measured and the experimental Q-factor of 2 . 47 × 108 and resonant depth of 109% were acquired separately. Compared with the resonator without the EDF, the resonant depth and Q-factor of the proposed device are increased by 2.5 times and 14 times, respectively. A potential optimum shot noise limited resolution of 0 . 042∘ / h can be obtained for the RFOG, which is promising for low-cost and high precise detection.

  20. Wavelength-selectable and steady single-mode erbium-doped fiber multiple ring laser

    Science.gov (United States)

    Yeh, Chien-Hung; Yang, Zi-Qing; Huang, Tzu-Jung; Chow, Chi-Wai; Chen, Jing-Heng; Chen, Kun-Huang

    2017-11-01

    To achieve a stable and selectable C-band erbium-doped fiber (EDF) laser with single-longitudinal-mode output, a multiple ring architecture is proposed and demonstrated experimentally. In this work, we design a passively quadruple-ring structure in the cavity of an EDF laser to produce a Vernier effect with a mode filter for suppressing the multimode spikes significantly. In addition, the output performance and stability of the proposed EDF ring laser are discussed.

  1. Stabilization in laser wavelength semiconductor with fiber optical amplifier application doped with erbium

    International Nuclear Information System (INIS)

    Camas, J.; Anzueto, G.; Mendoza, S.; Hernandez, H.; Garcia, C.; Vazquez, R.

    2009-01-01

    In this work, we present a novel electronic design of a DC source, which automatically controls the temperature of a tunable laser. The temperature change in the laser is carried out by the control of DC that circulates through a cooling stage where the laser is set. The laser can be tuned in a wavelength around 1550 nm. Its application is in Erbium Doped Fiber Amplifier (EDFA) in reflective configuration. (Author)

  2. Continuously tunable S and C+L bands ultra wideband erbium-doped fiber ring laser

    International Nuclear Information System (INIS)

    Wang, Q; Yu, Q X

    2009-01-01

    This paper presents an ultra wideband tunable silica-based erbium doped fiber ring laser (EDFRL) that can be continuously tuned in S and C+L bands from 1475 to 1619 nm. It is the first time that a fiber ring laser's tuning range reaches 144 nm using a standard silica-based C-band erbium-doped fiber as gain media. In the laser configuration two isolators are used in the fiber loop for suppressing the ASE in C-band and elevating the lasing gain in S-band. As a result the available lasing wavelength is extended toward the shorter wavelength of the gain bandwidth. The optimized erbium-doped fiber length, output coupling ratio and pumping laser power have been obtained through experimental study. This ring fiber laser has simple configuration, low threshold, flat laser spectral distribution and high signal-to-ASE-noise ratio. The laser will have many potential applications in fiber sensor wavelength interrogation, high-resolution spectroscopy and fiber optic communications

  3. Dynamic response analysis of DFB fibre lasers

    DEFF Research Database (Denmark)

    Yujun, Qian; Varming, Poul; Povlsen, Jørn Hedegaard

    1998-01-01

    We present a model for relative intensity noise (RIN) in DFB fibre lasers which predicts measured characteristics accurately. Calculation results implies that the RIN decreases rapidly with stronger Bragg grating and higher pump power. We propose here a simplified model based on three spatially...... independent rate equations to describe the dynamic response of erbium doped DFB fibre lasers on pump power fluctuations, using coupled-mode theory to calculate the steady-state hole-burning of the erbium ion inversion...

  4. Fibre amplifier based on an ytterbium-doped active tapered fibre for the generation of megawatt peak power ultrashort optical pulses

    Energy Technology Data Exchange (ETDEWEB)

    Koptev, M Yu; Anashkina, E A; Lipatov, D S; Andrianov, A V; Muravyev, S V; Kim, A V [Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod (Russian Federation); Bobkov, K K; Likhachev, M E; Levchenko, A E; Aleshkina, S S; Semjonov, S L; Denisov, A N; Bubnov, M M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Laptev, A Yu; Gur' yanov, A N [G.G.Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

    2015-05-31

    We report a new ytterbium-doped active tapered fibre used in the output amplifier stage of a fibre laser system for the generation of megawatt peak power ultrashort pulses in the microjoule energy range. The tapered fibre is single-mode at its input end (core and cladding diameters of 10 and 80 μm) and multimode at its output end (diameters of 45 and 430 μm), but ultrashort pulses are amplified in a quasi-single-mode regime. Using a hybrid Er/Yb fibre system comprising an erbium master oscillator and amplifier at a wavelength near 1.5 μm, a nonlinear wavelength converter to the 1 μm range and a three-stage ytterbium-doped fibre amplifier, we obtained pulses of 1 μJ energy and 7 ps duration, which were then compressed by a grating-pair dispersion compressor with 60% efficiency to a 130 fs duration, approaching the transform-limited pulse duration. The present experimental data agree well with numerical simulation results for pulse amplification in the threestage amplifier. (extreme light fields and their applications)

  5. Improvement of a triple-wavelength erbium-doped fiber laser using a Fabry–Perot laser diode

    International Nuclear Information System (INIS)

    Peng, P C; Hu, H L; Wang, J B

    2013-01-01

    This work demonstrates the feasibility of a simple construct of a tunable triple-wavelength fiber ring laser using a Fabry–Perot laser diode (FP-LD) and an optical tunable bandpass filter. An optical tunable bandpass filter is used within the cavity of an erbium-doped fiber laser to select the lasing wavelength. Because the Fabry–Perot laser diode is in combination with the tunable bandpass filter, the erbium-doped fiber laser can stably lase three wavelengths simultaneously. Moreover, this laser is easily tuned dynamically. This triple-wavelength output performs satisfactorily, with its optical side-mode-suppression-ratio (SMSR) exceeding 40 dB. Furthermore, the wavelength tuning range of this triple-wavelength erbium-doped fiber laser is greater than 27 nm. (paper)

  6. Modeling of Mid-IR Amplifier Based on an Erbium-Doped Chalcogenide Microsphere

    Directory of Open Access Journals (Sweden)

    P. Bia

    2012-01-01

    Full Text Available An optical amplifier based on a tapered fiber and an Er3+-doped chalcogenide microsphere is designed and optimized. A dedicated 3D numerical model, which exploits the coupled mode theory and the rate equations, is used. The main transitions among the erbium energy levels, the amplified spontaneous emission, and the most important secondary transitions pertaining to the ion-ion interactions have been considered. Both the pump and signal beams are efficiently injected and obtained by a suitable design of the taper angle and the fiber-microsphere gap. Moreover, a good overlapping between the optical signals and the rare-earth-doped region is also obtained. In order to evaluate the amplifier performance in reduced computational time, the doped area is partitioned in sectors. The obtained simulation results highlight that a high-efficiency midinfrared amplification can be obtained by using a quite small microsphere.

  7. New Erbium Doped Antimony Glasses for Laser and Glass ...

    African Journals Online (AJOL)

    Because of the special spectroscopic properties of the rare earth ions, rare earth doped glasses are widely used in bulk and fiber lasers or amplifiers. The modelling of lasers and searching for new laser transitions require a precise knowledge of the spectroscopic properties of rare earth ions in different host glasses.

  8. Graphene Oxide-Based Q-Switched Erbium-Doped Fiber Laser

    International Nuclear Information System (INIS)

    Yap, Y. K.; Harun, S. W.; Ahmad, H.; Huang, N. M.

    2013-01-01

    We demonstrate a pulsed ring erbium-doped fiber laser based on graphene oxide (GO), employing a simplified Hummer's method to synthesize the GO via chemical oxidation of graphite flakes at room temperature. By dipping a fiber ferrule end face onto the GO suspension, GO is successfully coated onto the end face, making it a simple saturable absorption device. A stable Q-switched pulsed fiber laser is achieved with a low pump threshold of 9.5 mW at 980 nm. The pulse repetition rate ranges from 16.0 to 57.0 kHz. The pulse width and the pulse energy are studied and discussed

  9. Erbium-doped yttrium aluminium garnet ablative laser treatment for endogenous ochronosis.

    Science.gov (United States)

    Chaptini, Cassandra; Huilgol, Shyamala C

    2015-08-01

    Ochronosis is a rare disease characterised clinically by bluish-grey skin discolouration and histologically by yellow-brown pigment deposits in the dermis. It occurs in endogenous and exogenous forms. Endogenous ochronosis, also known as alkaptonuria, is an autosomal recessive disease of tyrosine metabolism, resulting in the accumulation and deposition of homogentisic acid in connective tissue. We report a case of facial endogenous ochronosis and coexistent photodamage, which was successfully treated with erbium-doped yttrium aluminium garnet laser resurfacing and deep focal point treatment to remove areas of residual deep pigment. © 2014 The Australasian College of Dermatologists.

  10. Poor fluorinated graphene sheets carboxymethylcellulose polymer composite mode locker for erbium doped fiber laser

    Energy Technology Data Exchange (ETDEWEB)

    Mou, Chengbo, E-mail: mouc1@aston.ac.uk, E-mail: a.rozhin@aston.ac.uk; Turitsyn, Sergei; Rozhin, Aleksey, E-mail: mouc1@aston.ac.uk, E-mail: a.rozhin@aston.ac.uk [Aston Institute of Photonic Technologies, Aston University, Aston Triangle, Birmingham B4 7ET (United Kingdom); Arif, Raz [Aston Institute of Photonic Technologies, Aston University, Aston Triangle, Birmingham B4 7ET (United Kingdom); Physics Department, Faculty of Science, University of Sulaimani, Sulaimani, Kurdistan Region (Iraq); Lobach, Anatoly S.; Spitsina, Nataliya G. [Institute of Problems of Chemical Physics RAS, Ac. Semenov Av. 1, Chernogolovka, Moscow Region 142432 (Russian Federation); Khudyakov, Dmitry V. [Institute of Problems of Chemical Physics RAS, Ac. Semenov Av. 1, Chernogolovka, Moscow Region 142432 (Russian Federation); Physics Instrumentation Center of the Institute of General Physics A.M. Prokhorov Russian Academy of Sciences, Troitsk, Moscow Region 142190 (Russian Federation); Kazakov, Valery A. [Keldysh Center, Onezhskaya 8, Moscow 125438 (Russian Federation)

    2015-02-09

    We report poor fluorinated graphene sheets produced by thermal exfoliation embedding in carboxymethylcellulose polymer composite (GCMC) as an efficient mode locker for erbium doped fiber laser. Two GCMC mode lockers with different concentration have been fabricated. The GCMC based mode locked fiber laser shows stable soliton output pulse shaping with repetition rate of 28.5 MHz and output power of 5.5 mW was achieved with the high concentration GCMC, while a slightly higher output power of 6.9 mW was obtained using the low concentration GCMC mode locker.

  11. Monte Carlo simulations of homogeneous upconversion in erbium-doped silica glasses

    DEFF Research Database (Denmark)

    Philipsen, Jacob Lundgreen; Bjarklev, Anders Overgaard

    1997-01-01

    Quenching of Er3+ ions by homogeneous energy-transfer upconversion in high-concentration erbium-doped silica glasses has been theoretically investigated, The results indicate that at Er3+ concentrations of 1.0-2.0·1026 m-3 or below, the kinetic limit of strong migration is not reached, and hence...... the widely accepted quadratic upconversion model is not generally valid. Nevertheless, the results offer an explanation of the experimental observations of quadratic upconversion. Furthermore, it has been shown that at a given population inversion, the quenching rate depends on the rate of exchange...

  12. Performance analysis of bi-directional broadband passive optical network using erbium-doped fiber amplifier

    Science.gov (United States)

    Almalaq, Yasser; Matin, Mohammad A.

    2014-09-01

    The broadband passive optical network (BPON) has the ability to support high-speed data, voice, and video services to home and small businesses customers. In this work, the performance of bi-directional BPON is analyzed for both down and up streams traffic cases by the help of erbium doped fiber amplifier (EDFA). The importance of BPON is reduced cost. Because PBON uses a splitter the cost of the maintenance between the providers and the customers side is suitable. In the proposed research, BPON has been tested by the use of bit error rate (BER) analyzer. BER analyzer realizes maximum Q factor, minimum bit error rate, and eye height.

  13. Fibercore AstroGain fiber: multichannel erbium doped fibers for optical space communications

    Science.gov (United States)

    Hill, Mark; Gray, Rebecca; Hankey, Judith; Gillooly, Andy

    2014-03-01

    Fibercore have developed AstroGainTM fiber optimized for multichannel amplifiers used in optical satellite communications and control. The fiber has been designed to take full advantage of the photo-annealing effect that results from pumping in the 980nm region. The proprietary trivalent structure of the core matrix allows optimum recovery following radiation damage to the fiber, whilst also providing a market leading Erbium Doped Fiber Amplifier (EDFA) efficiency. Direct measurements have been taken of amplifier efficiency in a multichannel assembly, which show an effective photo-annealing recovery of up to 100% of the radiation induced attenuation through excitation of point defects.

  14. Linear all-fiber temperature sensor based on macro-bent erbium doped fiber

    International Nuclear Information System (INIS)

    Hajireza, P; Cham, C L; Kumar, D; Abdul-Rashid, H A; Emami, S D; Harun, S W

    2010-01-01

    A new all fiber temperature sensor is proposed and demonstrated based on a pair of 1 meter erbium-doped fiber (EDF), which are respectively macro-bent and straight. The sensor has a linear normalized loss (dB) response to temperature at 6.5 mm bending radius and 1580 nm input wavelength. The main advantage of this sensor is high temperature resolution (less than 1°C) and sensitivity (0.03 dB/°C) due to combination of temperature dependence of EDF and bending loss. The proposed silica based sensor, has the potential for wide range and high temperature applications in harsh environments

  15. Propagation of dispersion-nonlinearity-managed solitons in an inhomogeneous erbium-doped fiber system

    International Nuclear Information System (INIS)

    Mahalingam, A; Porsezian, K; Mani Rajan, M S; Uthayakumar, A

    2009-01-01

    In this paper, a generalized nonlinear Schroedinger-Maxwell-Bloch model with variable dispersion and nonlinearity management functions, which describes the propagation of optical pulses in an inhomogeneous erbium-doped fiber system under certain restrictive conditions, is under investigation. We derive the Lax pair with a variable spectral parameter and the exact soliton solution is generated from the Baecklund transformation. It is observed that stable solitons are possible only under a very restrictive condition for the spectral parameter and other inhomogeneous functions. For various forms of the inhomogeneous dispersion, nonlinearity and gain/loss functions, construction of different types of solitary waves like classical solitons, breathers, etc is discussed

  16. Synthesis and characterization of erbium-doped SiO2 nanoparticles fabricated by using reverse micelle and sol-gel processing

    International Nuclear Information System (INIS)

    Park, Hoyyul; Bae, Dongsik

    2012-01-01

    Erbium-doped SiO 2 nanoparticles have been synthesized using a reverse micelle technique combined with metal-alkoxide hydrolysis and condensation. The sizes and the morphologies of the erbium-doped SiO 2 nanoparticles could be changed by varying the molar ratio of water to surfactant. The sizes and the morphologies of the erbium-doped SiO 2 nanoparticles were examined by using a transmission electron microscope. The average size of synthesized erbium-doped SiO 2 nanoparticles was approximately 20 - 25 nm and that of the erbium particles was 3 - 5 nm. The effects of the synthesis parameters, such as the molar ratio of water to surfactant, are discussed.

  17. Electromagnetic waves in optical fibres in a magnetic field

    International Nuclear Information System (INIS)

    Gorelik, V S; Burdanova, M G

    2016-01-01

    A new method is reported of recording the secondary radiation of luminescent substances based on the use of capillary fibres of great length. Theoretical analysis of the dispersion curves of electromagnetic radiation in capillary fibres doped with erbium ions Er 3+ has been established. The Lorentz model is used for describing the dispersion properties of electromagnetic waves in a homogeneous medium doped with rare-earth ions. The dispersion dependencies of polariton and axion–polariton waves in erbium nitrate hydrate are determined on the basis of the model of the interaction between electromagnetic waves and the resonance electronic states of erbium ions in the absence and presence of a magnetic field. (paper)

  18. Erbium-doped fiber ring laser with SMS modal interferometer for hydrogen sensing

    Science.gov (United States)

    Zhang, Ya-nan; Zhang, Lebin; Han, Bo; Peng, Huijie; Zhou, Tianmin; Lv, Ri-qing

    2018-06-01

    A hydrogen sensor based on erbium-doped fiber ring laser with modal interferometer is proposed. A single mode-multimode-single mode (SMS) modal interferometer structure coated with Pd/WO3 film is used as the sensing head, due to that it is easy to be fabricated and low cost. The sensing structure is inserted into an erbium-doped fiber ring laser in order to solve the problem of spectral confusion and improve the detection limit of the hydrogen sensor based on the SMS modal interferometer. The SMS sensing structure is acted as a fiber band-pass filter. When hydrogen concentration around the sensor is changed, it will induce the refractive index and strain variations of the Pd/WO3 film, and then shift the resonant spectrum of the SMS modal interferometer as well as the laser wavelength of the fiber ring laser. Therefore, the hydrogen concentration can be measured by monitoring the wavelength shift of the laser, which has high intensity and narrow full width half maximum. Experimental results demonstrate that the sensor has high sensitivity of 1.23 nm/%, low detection limit of 0.017%, good stability and excellent repeatability.

  19. Recent progress of erbium-doped fiber amplifiers and their components

    Science.gov (United States)

    Fukushima, Masaru; Miura, Jutaro

    2007-09-01

    The Erbium-doped fiber amplifiers (EDFA) are widely available in a today's commercial market, and are deployed in various optical transmission applications from terrestrial system to undersea system. Broad gain spectrum over 9 THz enabled huge growth of bandwidth usage in 1550nm region aimed at broadband Internet, and its broad gain characteristics triggered bandwidth competition on dense wavelength division multiplex (DWDM) network these ten years. At first, we briefly review the evolutional history of EDFA with previous achievements. And we will explain the primary and important key devices which compose EDFA. We will discuss design parameters, and recent trend and achievements of the devices, which cover Erbium-doped fibers (EDF), 980-nm laser diodes (LD), and gain flattening filters (GFFs). The chip structure of 980-nm LD is explained to achieve high power and to realize high reliability. These key devices enabled EDFA to prevail in commercial area. After the discussion of key components, we will introduce recent achievements of gain controlled EDFAs which are applied in conjunction with Re-configurable Optical Add/Drop Multiplexer (ROADM). We will report the transient gain dynamics of the cascaded EDFAs with a recirculating loop experiment.

  20. All fiber passively mode locked zirconium-based erbium-doped fiber laser

    Science.gov (United States)

    Ahmad, H.; Awang, N. A.; Paul, M. C.; Pal, M.; Latif, A. A.; Harun, S. W.

    2012-04-01

    All passively mode locked erbium-doped fiber laser with a zirconium host is demonstrated. The fiber laser utilizes the Non-Linear Polarization Rotation (NPR) technique with an inexpensive fiber-based Polarization Beam Splitter (PBS) as the mode-locking element. A 2 m crystalline Zirconia-Yttria-Alumino-silicate fiber doped with erbium ions (Zr-Y-Al-EDF) acts as the gain medium and generates an Amplified Spontaneous Emission (ASE) spectrum from 1500 nm to 1650 nm. The generated mode-locked pulses have a spectrum ranging from 1548 nm to more than 1605 nm, as well as a 3-dB bandwidth of 12 nm. The mode-locked pulse train has an average output power level of 17 mW with a calculated peak power of 1.24 kW and energy per pulse of approximately 730 pJ. The spectrum also exhibits a Signal-to-Noise Ratio (SNR) of 50 dB as well as a repetition rate of 23.2 MHz. The system is very stable and shows little power fluctuation, in addition to being repeatable.

  1. Practical Method for engineering Erbium-doped fiber lasers from step-like pulse excitations

    International Nuclear Information System (INIS)

    Causado-Buelvas, J D; Gomez-Cardona, N D; Torres, P

    2011-01-01

    A simple method, known as 'easy points', has been applied to the characterization of Erbium-doped fibers, aiming for the engineering of fiber lasers. Using low- optical-power flattop pulse excitations it has been possible to determine both the attenuation coefficients and the intrinsic saturation powers of doped single-mode fibers at 980 and 1550 nm. Laser systems have been projected for which the optimal fiber length and output power have been determined as a function of the input power. Ring and linear laser cavities have been set up, and the characteristics of the output laser have been obtained and compared with the theoretical predictions based on the 'easy points' parameters.

  2. Broadband features of passively harmonic mode locking in dispersion-managed erbium-doped all-fiber lasers

    Science.gov (United States)

    Geng, Y.; Li, L.; Shu, C. J.; Wang, Y. F.; Tang, D. Y.; Zhao, L. M.

    2018-06-01

    Broadband features of passively harmonic mode locking (HML) in dispersion-managed erbium-doped all-fiber lasers are explored. The bandwidth of HML state is generally narrower than that of fundamental mode locking before pulse breaking occurs. There exists a broadest bandwidth versus the order of HML. HML state with bandwidth up to 61.5 nm is obtained.

  3. 32-core erbium/ytterbium-doped multicore fiber amplifier for next generation space-division multiplexed transmission system

    DEFF Research Database (Denmark)

    Jain, Saurabh; Castro, Carlos; Jung, Yongmin

    2017-01-01

    We present a high-core-count 32-core multicore erbium/ytterbium-doped fiber amplifier (32c-MC-EYDFA) in a cladding pumped configuration. A side pumping technique is employed for ease of pump coupling in this monolithic all-fiber amplifier. A minimum gain of >17 dB and an average noise figure (NF)...

  4. Characterization of an erbium doped fiber amplifier starting from its experimental parameters; Caracterizacion de un amplificador de fibra dopada con erbio a partir de sus parametros experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Bello J, M.; Kuzin, E.A.; Ibarra E, B. [Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Luis Enrique Erro No. 1, TonantzintIa, 72000 Puebla (Mexico); Tellez G, R. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No 152, Delegacion Gustavo A. Madero, 07730 Mexico D.F. (Mexico)]. e-mail: mabello@inaoep.mx

    2007-07-01

    In this paper we describe a method to characterize the gain of an erbium-doped fiber amplifier (EDFA) through the numerical simulation of the signal beam along the amplifier. The simulation is based on a model constituted by the propagation and rate equations for an erbium-doped fiber. The manipulation of these equations allows us to regroup the parameters present in an EDFA, which we have named the A, B, C, D parameters, and they can be obtained experimentally from an erbium-doped fiber. Experimental results show that the measurement of these parameters allow us to estimate with very good correspondence the amplifier gain. (Author)

  5. STRUCTURE FEATURES OF THE SODIUM-GERMANATE GLASSES DOPED WITH YTTERBIUM ERBIUM RETRIEVED FROM RAMAN SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    I. M. Sevastianova

    2016-09-01

    Full Text Available Subject of Research.The paper deals with study of Raman spectra and luminescence spectra in the visible region of the sodium-germanate glass: 49 GeO2 – 13 Na2O – 27 Yb2O3 – 11 La2O3 - 0,25 Er2O3 and presents research results. In addition, this glass is doped with 5 mol% of the following components MgO, BaO, Al2O3, PbO, Nb2O5, TiO2, SiO2, P2O5 in order to study the effect of these additives on the structure of the glassy matrix and the anti-Stokes luminescence spectra of erbium ions. Method. Raman scatteringspectra were recorded by Renishaw inVia Raman Microscope. Excitation source is a helium neon laser (λ= 633 nm with power equal to 50Wt. Anti-Stokes luminescence of erbium ions was registered in spectral region of 450–750 nm at room temperature (excitation laser wavelength is 975 nm, power is 1Wt. Main Results. It was shown that the structure of the initial glass does not change with the introduction of niobium as Nb2O5 in any coordination plays a role of network forming, building a single mixed grid with tetrahedrons [GeO4]. Introduction of the second glass former P2O5 leads to loosening germanate structure due to the appearance of the phosphate sublattice. This leads to a redistribution of the relative intensity of up-conversion luminescence bands with maxima at 540 and 670 nm compared with the initial glass. Introduction of additives PbO, MgO, Al2O3, TiO2 results in a multicenter structure. In case of titanium oxide addition it leads to a change in the relative intensities of the erbium luminescence.

  6. Dynamic population gratings in rare-earth-doped optical fibres

    Energy Technology Data Exchange (ETDEWEB)

    Stepanov, Serguei [Optics Department, CICESE, km.107 carr. Tijuana-Ensenada, Ensenada, 22860, BC (Mexico)], E-mail: steps@cicese.mx

    2008-11-21

    Dynamic Bragg gratings can be recorded in rare-earth (e.g. Er, Yb) doped optical fibres by two counter-propagating mutually coherent laser waves via local saturation of the fibre optical absorption or gain (in optically pumped fibres). Typical recording cw light power needed for efficient grating formation is of sub-mW-mW scale which results in characteristic recording/erasure times of 10-0.1 ms. This review paper discusses fundamental aspects of the population grating formation, their basic properties, relating wave-mixing processes and also considers different applications of these dynamic gratings in single-frequency fibre lasers, tunable filters, optical fibre sensors and adaptive interferometry.

  7. Dynamic population gratings in rare-earth-doped optical fibres

    International Nuclear Information System (INIS)

    Stepanov, Serguei

    2008-01-01

    Dynamic Bragg gratings can be recorded in rare-earth (e.g. Er, Yb) doped optical fibres by two counter-propagating mutually coherent laser waves via local saturation of the fibre optical absorption or gain (in optically pumped fibres). Typical recording cw light power needed for efficient grating formation is of sub-mW-mW scale which results in characteristic recording/erasure times of 10-0.1 ms. This review paper discusses fundamental aspects of the population grating formation, their basic properties, relating wave-mixing processes and also considers different applications of these dynamic gratings in single-frequency fibre lasers, tunable filters, optical fibre sensors and adaptive interferometry.

  8. Treatment of dilated pores with 1410-nm fractional erbium-doped fiber laser.

    Science.gov (United States)

    Suh, Dong-Hye; Chang, Ka-Yeun; Lee, Sang-Jun; Song, Kye-Yong; Choi, Jeong Hwee; Shin, Min Kyung; Jeong, Ki-Heon

    2015-04-01

    Dilated pores can be an early sign of skin aging and are a significant cosmetic concern. The 1410-nm wavelength is optimal for superficial dermal treatments up to 650 μm deep. The aim of the present study was to evaluate the clinical effectiveness and safety of the fractional erbium-doped fiber 1410-nm laser in the treatment of dilated pores. Fifteen patients with dilated facial pores underwent three laser treatments at 3-week intervals. Posttreatment skin responses and side effects were assessed at treatment and follow-up visits by study physicians. Clinical effectiveness of treatment was assessed by both study physicians and patients 3 months after the final laser treatment using a quartile grading scale. Histological examination was performed using biopsy samples taken at baseline (pretreatment) and 3 months after the last treatment. This study showed that greater than 51 % improvement in dilated pores was demonstrated in 14 of 15 patients after three sessions of laser treatments. Improvements in skin texture, tone, and smoothness were reported in all patients. Treatment was well tolerated in all patients, with no unanticipated side effects. This study demonstrates that the 1410-nm fractional erbium fiber laser is effective and safe for treatment of dilated facial pores in Fitzpatrick skin types III-IV.

  9. Tungsten diselenide for mode-locked erbium-doped fiber lasers with short pulse duration

    Science.gov (United States)

    Liu, Wenjun; Liu, Mengli; OuYang, Yuyi; Hou, Huanran; Ma, Guoli; Lei, Ming; Wei, Zhiyi

    2018-04-01

    In this paper, a WSe2 film prepared by chemical vapor deposition (CVD) is transferred onto a tapered fiber, and a WSe2 saturable absorber (SA) is fabricated. In order to measure the third-order optical nonlinearity of the WSe2, the Z-scan technique is applied. The modulation depth of the WSe2 SA is measured as being 21.89%. Taking advantage of the remarkable nonlinear absorption characteristic of the WSe2 SA, a mode-locked erbium-doped fiber laser is demonstrated at 1557.4 nm with a bandwidth of 25.8 nm and signal to noise ratio of 96 dB. To the best of our knowledge, the pulse duration of 163.5 fs is confirmed to be the shortest compared with previous mode-locked fiber lasers based on transition-metal dichalcogenides SAs. These results indicate that WSe2 is a powerful competitor in the application of ultrashort pulse lasers.

  10. Accelerated two-wave mixing response in erbium-doped fibers with saturable optical absorption

    Science.gov (United States)

    Hernandez, Eliseo; Stepanov, Serguei; Plata Sanchez, Marcos

    2016-08-01

    The contribution of the spatially uniform variation of average optical absorption to the dynamics of the transient two-wave mixing (TWM) response is considered. It is shown theoretically and confirmed experimentally that this transient effect, via dynamic population gratings in erbium-doped fibers (EDFs) can ensure a response nearly two times faster in such gratings as compared to the growth rate of fluorescence uniformly excited under similar conditions, and can also result in an additional overshot in the tail of the TWM response. This additional ‘accelerating’ contribution is of even type, and does not influence the odd transient TWM response for the refractive index component of such gratings in the EDFs reported earlier. It is also shown that this effect can be utilized to monitor the formation of the dynamic grating with an auxiliary probe wave of the essentially different non-Bragg wavelength.

  11. Giant Pulse Phenomena in a High Gain Erbium Doped Fiber Amplifier

    Science.gov (United States)

    Li, Stephen X.; Merritt, Scott; Krainak, Michael A.; Yu, Anthony

    2018-01-01

    High gain Erbium Doped Fiber Amplifiers (EDFAs) are vulnerable to optical damage when unseeded, e.g. due to nonlinear effects that produce random, spontaneous Q-switched (SQS) pulses with high peak power, i.e. giant pulses. Giant pulses can damage either the components within a high gain EDFA or external components and systems coupled to the EDFA. We explore the conditions under which a reflective, polarization-maintaining (PM), core-pumped high gain EDFA generates giant pulses, provide details on the evolution of normal pulses into giant pulses, and provide results on the transient effects of giant pulses on an amplifier's fused-fiber couplers, an effect which we call Fiber Overload Induced Leakage (FOIL). While FOIL's effect on fused-fiber couplers is temporary, its damage to forward pump lasers in a high gain EDFA can be permanent.

  12. A Q-Switched Erbium-Doped Fiber Laser with a Carbon Nanotube Based Saturable Absorber

    International Nuclear Information System (INIS)

    Harun, S. W.; Ismail, M. A.; Ahmad, F.; Ismail, M. F.; Nor, R. M.; Zulkepely, N. R.; Ahmad, H.

    2012-01-01

    We demonstrate a simple, compact and low cost Q-switched erbium-doped fiber laser (EDFL) using single-wall carbon nanotubes (CNTs) as a saturable absorber for possible applications in metrology, sensing, and medical diagnostics. The EDFL operates at around 1560 nm with repetition rates of 16.1 kHz and 6.4 kHz with saturable absorbers SA1 and SA2 at a pump power of 120 mW. The absorbers are constructed by optically driven deposition and normal deposition techniques. It is observed that the optical deposition method produces a Q-switched EDFL with a lower threshold of 70 mW and better Q-switching performance compared to that of the normal deposition method. The EDFL also has pulse energy of 90.3 nJ and pulse width of 11.6 μs at 120 mW pump power

  13. Luminescence properties of erbium doped sodium barium borate glass with silver nanoparticles

    Science.gov (United States)

    Rajeshree Patwari, D.; Eraiah, B.

    2018-02-01

    Alteration in the absorption features of rare earth (RE) doped glasses with silver nanoparticles is ever-challenging in photonics. Erbium (Er3+) doped glasses with composition (60-x-y)B2O3-30Na2CO3-10BaO-xEr2O3-yAgCl where (x=0.5, 1.0 and y=1.0 mol %) are synthesized using melt-quenching method. The density is determined by Archimedes principle and molar volumes are calculated. Glass samples were characterized by XRD and UV-Visible spectroscopy. UV-Visible spectra shows eleven prominent absorption peaks centred around 366, 378, 408, 442, 452, 489, 521, 547, 652, 800 and 977 nm equivalent to the rare earth (Er3+) ion transitions. The sample without rare earth shows no peaks which specifies that rare earth ion plays a spirited role in the glass matrix. The glass samples with silver and without rare earth ion shows plasmon peak on heat treatment. The energy band gap values calculated for direct and indirect transitions are in the range of 3.126-3.440eV and 2.58-3.177eV respectively. The refractive indices and Urbach energies are also determined. Photoluminescence spectra are recorded and studied for excitation of the most intense peaks of wavelengths 378 and 521nm. The luminescence of erbium ion is enhanced by the presence of silver when the concentration of rare earth ion is less than that of silver.

  14. Temperature-Insensitive Bend Sensor Using Entirely Centered Erbium Doping in the Fiber Core

    Directory of Open Access Journals (Sweden)

    Sulaiman Wadi Harun

    2013-07-01

    Full Text Available A fiber based bend sensor using a uniquely designed Bend-Sensitive Erbium Doped Fiber (BSEDF is proposed and demonstrated. The BSEDF has two core regions, namely an undoped outer region with a diameter of about 9.38 μm encompassing a doped, inner core region with a diameter of 4.00 μm. The doped core region has about 400 ppm of an Er2O3 dopant. Pumping the BSEDF with a conventional 980 nm laser diode gives an Amplified Spontaneous Emission (ASE spectrum spanning from 1,510 nm to over 1,560 nm at the output power level of about −58 dBm. The ASE spectrum has a peak power of −52 dBm at a central wavelength of 1,533 nm when not spooled. Spooling the BSEDF with diameters of 10 cm to 2 cm yields decreasing peak powers from −57.0 dBm to −61.8 dBm, while the central wavelength remains unchanged. The output is highly stable over time, with a low temperature sensitivity of around ~0.005 dBm/°C, thus allowing for the development of a highly stable sensor system based in the change of the peak power alone.

  15. Amplification of 12 OAM Modes in an air-core erbium doped fiber.

    Science.gov (United States)

    Kang, Qiongyue; Gregg, Patrick; Jung, Yongmin; Lim, Ee Leong; Alam, Shaif-ul; Ramachandran, Siddharth; Richardson, David J

    2015-11-02

    We theoretically propose an air-core erbium doped fiber amplifier capable of providing relatively uniform gain for 12 orbital angular momentum (OAM) modes (|L| = 5, 6 and 7, where |L| is the OAM mode order) over the C-band. Amplifier performance under core pumping conditions for a uniformly doped core for each of the supported pump modes (110 in total) was separately assessed. The differential modal gain (DMG) was found to vary significantly depending on the pump mode used, and the minimum DMG was found to be 0.25 dB at 1550 nm provided by the OAM (8,1) pump mode. A tailored confined doping profile can help to reduce the pump mode dependency for core pumped operation and help to increase the number of pump modes that can support a DMG below 1 dB. For the more practical case of cladding-pumped operation, where the pump mode dependency is almost removed, a DMG of 0.25 dB and a small signal gain of >20 dB can be achieved for the 12 OAM modes across the full C-band.

  16. Performance Comparison of Mode-Locked Erbium-Doped Fiber Laser with Nonlinear Polarization Rotation and Saturable Absorber Approaches

    International Nuclear Information System (INIS)

    Ismail, M. A.; Tan, S. J.; Shahabuddin, N. S.; Harun, S. W.; Arof, H.; Ahmad, H.

    2012-01-01

    A mode-locked erbium-doped fiber laser (EDFL) is demonstrated using a highly concentrated erbium-doped fiber (EDF) as the gain medium in a ring configuration with and without a saturable absorber (SA). Without the SA, the proposed laser generates soliton pulses with a repetition rate of 12 MHz, pulse width of 1.11 ps and energy pulse of 1.6 pJ. By incorporating SA in the ring cavity, the optical output of the laser changes from soliton to stretched pulses due to the slight change in the group velocity dispersion. With the SA, a cleaner pulse is obtained with a repetition rate of 11.3 MHz, a pulse width of 0.58 ps and a pulse energy of 2.3 pJ. (fundamental areas of phenomenology(including applications))

  17. Tunable and switchable multi-wavelength erbium-doped fiber laser with highly nonlinear photonic crystal fiber and polarization controllers

    International Nuclear Information System (INIS)

    Liu, X M; Lin, A; Zhao, W; Lu, K Q; Wang, Y S; Zhang, T Y; Chung, Y

    2008-01-01

    We have proposed a novel multi-wavelength erbium-doped fiber laser by using two polarization controllers and a sampled chirped fiber Bragg grating(SC-FBG). On the assistance of SC-FBG, the proposed fiber lasers with excellent stability and uniformity are tunable and switchable by adjusting the polarization controllers. Our laser can stably lase two waves and up to eight waves simultaneously at room temperature

  18. Structural characterization, optical properties and in vitro bioactivity of mesoporous erbium-doped hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Alshemary, Ammar Z.; Akram, Muhammed; Goh, Yi-Fan [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Abdul Kadir, Mohammed Rafiq [Medical Implant Technology Group, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Abdolahi, Ahmad [Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Hussain, Rafaqat, E-mail: rafaqat@kimia.fs.utm.my [Centre for Sustainable Nanomaterials (CSNano), Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia)

    2015-10-05

    Highlights: • Phase pure nano-sized Er doped hydroxyapatite has been prepared. • TEM micrograph confirmed formation of mesoporous material. • Increased Er doping resulted in blue shift with slight increase in energy band gab. • Er-HA showed better dissolution behavior in SBF comparing with pure HA. • Er doping of HA resulted in formation of apatite layer in SBF with Ca/P ratio of 1.72. - Abstract: We report the successful synthesis of mesoporous erbium doped hydroxyapatite (Er-HA, Ca{sub 10−x}Er{sub 2x/3}□{sub x/3}(PO{sub 4}){sub 6}(OH){sub 2}) by using a rapid and efficient microwave assisted wet precipitation method. Characterization techniques like X-ray diffraction (XRD), Fourier transform infra-red (FTIR), X-ray fluorescence spectrometer (XRF), Brunauer, Emmett and Teller (BET) and transmission electron microscopy (TEM) were used to determine lattice parameters, particle size, degree of crystallinity, elemental composition, surface area and morphology of Er-HA. Results confirmed the formation of crystalline Er-HA having crystallite size of 25 nm with spherical and rod like morphology, while the TEM analysis confirmed the mesoporous nature of the particles. Optical spectra of Er-HA contained seven electron transitions, whereas blue shift in the energy band gap (E{sub g}) was observed upon increase in Er{sup 3+} content. The photoluminescence (PL) spectra contained green and red emissions. In vitro bioactivity study conducted in SBF revealed that the incorporation of Er{sup 3+} ions into HA structure lead to the faster discharge of Er{sup 3+} ions resulting in intense growth of apatite grains on the surface of the Er-HA pellets with Ca/P ratio of 1.72.

  19. Optimized radiation-hardened erbium doped fiber amplifiers for long space missions

    Science.gov (United States)

    Ladaci, A.; Girard, S.; Mescia, L.; Robin, T.; Laurent, A.; Cadier, B.; Boutillier, M.; Ouerdane, Y.; Boukenter, A.

    2017-04-01

    In this work, we developed and exploited simulation tools to optimize the performances of rare earth doped fiber amplifiers (REDFAs) for space missions. To describe these systems, a state-of-the-art model based on the rate equations and the particle swarm optimization technique is developed in which we also consider the main radiation effect on REDFA: the radiation induced attenuation (RIA). After the validation of this tool set by confrontation between theoretical and experimental results, we investigate how the deleterious radiation effects on the amplifier performance can be mitigated following adequate strategies to conceive the REDFA architecture. The tool set was validated by comparing the calculated Erbium-doped fiber amplifier (EDFA) gain degradation under X-rays at ˜300 krad(SiO2) with the corresponding experimental results. Two versions of the same fibers were used in this work, a standard optical fiber and a radiation hardened fiber, obtained by loading the previous fiber with hydrogen gas. Based on these fibers, standard and radiation hardened EDFAs were manufactured and tested in different operating configurations, and the obtained data were compared with simulation data done considering the same EDFA structure and fiber properties. This comparison reveals a good agreement between simulated gain and experimental data (vulnerability in terms of gain. The presented approach is a complementary and effective tool for hardening by device techniques and opens new perspectives for the applications of REDFAs and lasers in harsh environments.

  20. High-power microcavity lasers based on highly erbium-doped sol-gel aluminosilicate glasses

    International Nuclear Information System (INIS)

    Le Ngoc Chung; Chu Thi Thu Ha; Nguyen Thu Trang; Pham Thu Nga; Pham Van Hoi; Bui Van Thien

    2006-01-01

    High-power whispering-gallery-mode (WGM) lasing from highly erbium-doped sol-gel aluminosilicate microsphere cavity coupled to a half-tapered optical fiber is presented. The lasing output power as high as 0.45 mW (-3.5 dBm) was obtained from sol-gel glass microsphere cavity with diameters in the range of 40-150 μm. The sol-gel method for making highly concentration Er-doped aluminosilicate glasses with Er-ion concentrations from 0.125 to 0.65 mol% of Er 3+ is described. Controlling collected lasing wavelength at each WGM is possible by adjusting the distance between the half-taper fiber and the microcavity and by diameter of the waist of half-taper fiber. Using the analytic formulas we calculated the TE and TM lasing modes and it is shown that the experimental results are in good agreement with the calculation prediction

  1. Efficient high power operation of erbium 3 µm fibre laser diode-pumped at 975 nm

    NARCIS (Netherlands)

    Jackson, S.D.; King, T.A.; Pollnau, Markus

    2000-01-01

    Efficient CW operation of a 2.71 um Er,Pr:ZBLAN double-clad fibre laser pumped with a single diode laser operating at a wavelength of 975 nm is described. A maximum output power of 0.5 W and a slope efficiency of 25% (with respect to the launched pump power) were obtained. Threshold pump powers of <

  2. All-fibre Q-switching YDFL operation with bismuth-doped fibre as saturable absorber

    Science.gov (United States)

    Muhammad, A. R.; Haris, H.; Arof, H.; Tan, S. J.; Ahmad, M. T.; Harun, S. W.

    2018-05-01

    We demonstrate the generation of a passively Q-switched ytterbium-doped fibre laser (YDFL) using a bismuth-doped fibre (BDF) as a solid-state fibre saturable absorber (FSA) in a ring cavity. The BDF used has a wide and low absorption band of 5 dB/m at the 1.0 μm region due to the ion transition of ? that occurs around the region. When introduced into a YDFL laser cavity, a stable Q-switched pulse operation was observed and the pulse repetition rate was proportional to the input pump power. It was limited to 72.99 kHz by the maximum power that the laser diode could supply. Meanwhile, the pulse width decreased from 12.22 to 4.85 μs as the pump power was increased from 215.6 to 475.6 mW. The finding suggests that BDF could be used as a potential SA for the development of robust, compact, efficient and low cost Q-switched fibre lasers operating at 1 micron region.

  3. Dark solitons in erbium-doped fiber lasers based on indium tin oxide as saturable absorbers

    Science.gov (United States)

    Guo, Jia; Zhang, Huanian; Li, Zhen; Sheng, Yingqiang; Guo, Quanxin; Han, Xile; Liu, Yanjun; Man, Baoyuan; Ning, Tingyin; Jiang, Shouzhen

    2018-04-01

    Dark solitons, which have good stability, long transmission distance and strong anti-interference ability. By using a coprecipitation method, the high quality indium tin oxide (ITO) were prepared with an average diameter of 34.1 nm. We used a typical Z-scan scheme involving a balanced twin-detector measurement system to investigated nonlinear optical properties of the ITO nanoparticles. The saturation intensity and modulation depths are 13.21 MW/cm2 and 0.48%, respectively. In an erbium-doped fiber (EDF) lasers, we using the ITO nanoparticles as saturable absorber (SA), and the formation of dark soliton is experimentally demonstrated. The generated dark solitons are centered at the wavelength of 1561.1 nm with a repetition rate of 22.06 MHz. Besides, the pulse width and pulse-to-pulse interval of the dark solitons is ∼1.33ns and 45.11 ns, respectively. These results indicate that the ITO nanoparticles is a promising nanomaterial for ultrafast photonics.

  4. Pure antimony film as saturable absorber for Q-switched erbium-doped fiber laser

    Science.gov (United States)

    Rahman, M. F. A.; Zhalilah, M. Z.; Latiff, A. A.; Rosol, A. H. A.; Lokman, M. Q.; Bushroa, A. R.; Dimyati, K.; Harun, S. W.

    2018-04-01

    This paper reports on the use of Antimony (Sb) polymer film to generate stable Q-switching pulses in Erbium-doped fiber laser (EDFL) cavity. The SA is fabricated by coating a thin layer of Sb on a polyvinyl alcohol (PVA) film through physical vapour deposition (PVD) process. A 1 × 1 mm area of the film SA is cut and integrated into between two fiber ferrules inside the laser cavity for intra-cavity loss modulation. Self-starting and stable Q-switched pulses are obtained within a pump power range from 60 to 142 mW. Within this range, the repetition rate increases from 70.82 to 98.04 kHz, while pulse width decreases from 7.42 to 5.36 μs. The fundamental frequency signal-to-noise ratio of the pulse signal is 74 dB, which indicates the excellent stability of the pulses. The maximum output power and pulse energy are 8.45 mW and 86.19 nJ, respectively. Our demonstration shows that Sb film SA capable of generating stable pulses train operating at 1.55-micron region.

  5. Adaptive Neuro-Fuzzy Based Gain Controller for Erbium-Doped Fiber Amplifiers

    Directory of Open Access Journals (Sweden)

    YUCEL, M.

    2017-02-01

    Full Text Available Erbium-doped fiber amplifiers (EDFA must have a flat gain profile which is a very important parameter such as wavelength division multiplexing (WDM and dense WDM (DWDM applications for long-haul optical communication systems and networks. For this reason, it is crucial to hold a stable signal power per optical channel. For the purpose of overcoming performance decline of optical networks and long-haul optical systems, the gain of the EDFA must be controlled for it to be fixed at a high speed. In this study, due to the signal power attenuation in long-haul fiber optic communication systems and non-equal signal amplification in each channel, an automatic gain controller (AGC is designed based on the adaptive neuro-fuzzy inference system (ANFIS for EDFAs. The intelligent gain controller is implemented and the performance of this new electronic control method is demonstrated. The proposed ANFIS-based AGC-EDFA uses the experimental dataset to produce the ANFIS-based sets and the rule base. Laser diode currents are predicted within the accuracy rating over 98 percent with the proposed ANFIS-based system. Upon comparing ANFIS-based AGC-EDFA and experimental results, they were found to be very close and compatible.

  6. Visible and infrared photoluminescence from erbium-doped silicon nanocrystals produced by rf sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Cerqueira, M.F.; Alpuim, P. [Departamento de Fisica, Universidade do Minho, Braga (Portugal); Losurdo, M. [Plasma Chemistry Research Center, CNR, Bari (Italy); Monteiro, T.; Soares, M.J.; Peres, M. [Departamento de Fisica, Universidade de Aveiro, Aveiro (Portugal); Stepikova, M. [Institute for Physics of Microstructures RAS, 603600 Nizhnij Novgorod GSP-105 (Russian Federation)

    2007-06-15

    Erbium-doped low-dimensional Si films with different microstructures were deposited by reactive magnetron sputtering on glass substrates by varying the hydrogen flow rate during deposition. Amorphous, micro- and nanocrystalline samples, consisting of Si nanocrystalls embedded in silicon-based matrices with different structures, were achieved with optical properties in the visible and IR depending on nanocrystalline fraction and matrix structure and chemical composition. Structural characterization was performed by X-ray diffraction in the grazing incidence geometry and Raman spectroscopy. The chemical composition was studied using RBS/ERD techniques. Spectroscopic ellipsometry was combined with the previous techniques to further resolve the film microstructure and composition. In particular, the distribution along the film thickness of the volume fractions of nanocrystalline/amorphous silicon and SiO{sub x} phases has been obtained. In this contribution we discuss visible and infrared photoluminescence as a function of sample microstructure and of the oxygen/hydrogen concentration ratio present in the matrix. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Self-Q-switching behavior of erbium-doped tellurite microstructured fiber lasers

    International Nuclear Information System (INIS)

    Jia, Zhi-Xu; Yao, Chuan-Fei; Kang, Zhe; Qin, Guan-Shi; Qin, Wei-Ping; Ohishi, Yasutake

    2014-01-01

    We reported self-Q-switching behavior of erbium-doped tellurite microstructured fiber (EDTMF) lasers and further demonstrated a self-Q-switched EDTMF laser with a high repetition rate of more than 1 MHz. A 14 cm EDTMF was used as the gain medium. Upon a pump power of ∼705 mW at 1480 nm, output pulses with a lasing wavelength of ∼1558 nm, a repetition rate of ∼1.14 MHz, and a pulse width of ∼282 ns were generated from the fiber by employing a linear cavity. The maximum output power was ∼316 mW and the slope efficiency was about 72.6% before the saturation of the laser power. Moreover, the influence of the fiber length on laser performances was investigated. The results showed that self-Q-switching behavior in our experiments was caused by the re-absorption originated from the ineffectively pumped part of the active fiber.

  8. Electron irradiation response on Ge and Al-doped SiO{sub 2} optical fibres

    Energy Technology Data Exchange (ETDEWEB)

    Yaakob, N.H.; Wagiran, H. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Hossain, I., E-mail: imamhossain@utm.m [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Ramli, A.T. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Bradley, D.A [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Hashim, S. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Ali, H. [Department of Radiotherapy and Oncology, Hospital Sultan Ismail, Johor Darul Takzim (Malaysia)

    2011-05-01

    This paper describes the thermoluminescence response, sensitivity, stability and reproducibility of SiO{sub 2} optical fibres with various electron energies and doses. The TL materials that comprise Al- and Ge-doped silica fibres were used in this experiment. The TL results are compared with those of the commercially available TLD-100. The doped SiO{sub 2} optical fibres and TLD-100 are placed in a solid phantom and irradiated with 6, 9 and 12 MeV electron beams at doses ranging from 0.2 to 4.0 Gy using the LINAC at Hospital Sultan Ismail, Johor Bahru, Malaysia. It was found that the commercially available Al- and Ge-doped optical fibres have a linear dose-TL signal relationship. The intensity of TL response of Ge-doped fibre is markedly greater than that of the Al-doped fibre.

  9. Electron irradiation response on Ge and Al-doped SiO 2 optical fibres

    Science.gov (United States)

    Yaakob, N. H.; Wagiran, H.; Hossain, I.; Ramli, A. T.; Bradley, D. A.; Hashim, S.; Ali, H.

    2011-05-01

    This paper describes the thermoluminescence response, sensitivity, stability and reproducibility of SiO 2 optical fibres with various electron energies and doses. The TL materials that comprise Al- and Ge-doped silica fibres were used in this experiment. The TL results are compared with those of the commercially available TLD-100. The doped SiO 2 optical fibres and TLD-100 are placed in a solid phantom and irradiated with 6, 9 and 12 MeV electron beams at doses ranging from 0.2 to 4.0 Gy using the LINAC at Hospital Sultan Ismail, Johor Bahru, Malaysia. It was found that the commercially available Al- and Ge-doped optical fibres have a linear dose-TL signal relationship. The intensity of TL response of Ge-doped fibre is markedly greater than that of the Al-doped fibre.

  10. Electron irradiation response on Ge and Al-doped SiO2 optical fibres

    International Nuclear Information System (INIS)

    Yaakob, N.H.; Wagiran, H.; Hossain, I.; Ramli, A.T.; Bradley, D.A; Hashim, S.; Ali, H.

    2011-01-01

    This paper describes the thermoluminescence response, sensitivity, stability and reproducibility of SiO 2 optical fibres with various electron energies and doses. The TL materials that comprise Al- and Ge-doped silica fibres were used in this experiment. The TL results are compared with those of the commercially available TLD-100. The doped SiO 2 optical fibres and TLD-100 are placed in a solid phantom and irradiated with 6, 9 and 12 MeV electron beams at doses ranging from 0.2 to 4.0 Gy using the LINAC at Hospital Sultan Ismail, Johor Bahru, Malaysia. It was found that the commercially available Al- and Ge-doped optical fibres have a linear dose-TL signal relationship. The intensity of TL response of Ge-doped fibre is markedly greater than that of the Al-doped fibre.

  11. Enhanced local piezoelectric response in the erbium-doped ZnO nanostructures prepared by wet chemical synthesis

    Directory of Open Access Journals (Sweden)

    Reza Zamiri

    2017-03-01

    Full Text Available Pure and erbium (Er doped ZnO nanostructures were prepared by simple and cost effective wet chemical precipitation method. The successful doping with phase purity of prepared ZnO nanostructure was confirmed by X-ray diffraction (XRD and their Rietveld analysis. The change in structural morphology of nanoscale features of prepared ZnO nanopowders on Er doping was observed from their scanning electron microscopy (SEM images. The presence of Er in prepared ZnO nanopowder was further confirmed from corresponding energy dispersive X-ray spectroscopy (EDX spectra of scanned SEM images. Piezoelectric properties of before (green samples and after sintering of consolidated compact of synthesized nanopowders were successfully measured. The out-of-plane (effective longitudinal and in-plane (effective shear coefficients of the samples were estimated from the local piezoresponse.

  12. Gain claming in single-pass and double-pass L-band erbium-doped fiber amplifiers

    International Nuclear Information System (INIS)

    Harun, S.W.; Ahmad, H.

    2004-01-01

    Gain clamping is demonstrated in single-pass and double-pass long wavelength band erbium-doped fiber amplifiers. A C/L-band wavelength division multiplexing coupler is used in single-pass system to generate a laser at 1566 nm. The gain for the amplifier is clamped at 15.5 dB with gain variation of less than 0.2 dB from input signal power of -40 to -14 dBm with almost negligible noise figure penalty. However, the flatness of gain spectrum is slightly degraded due to the un-optimisation of erbium-doped fiber length. The advantage of this configuration is that the oscillating light does not appear at the output of the amplifier. A highly efficient gain-clamped long wavelength band erbium-doped fiber amplifiers with improved noise figure characteristic is demonstrated by simply adding a broadband conventional band fiber Bragg grating in double pass system. The combination of the fiber Bragg grating and optical circulator has created laser in the cavity for gain clamping. By adjusting the power combination of pumps 1 and 2, the clamped gain level can be controlled. The amplifier gain is clamped at 28.1 dB from -40 to -25 dBm with gain variation of less than 0.5 dB by setting the pumps 1 and 2 at 59.5 and 50.6 mW, respectively. The gain is also flat from 1574 nm to 1604 nm with gain variation of less than 3 dB. The corresponding noise figure varies from 5.6 to 7.6 dB, which is 0.8 to 2.6 dB reduced compared to those of unclamped amplifier (Authors)

  13. 75 W 40% efficiency single-mode all-fiber erbium-doped laser cladding pumped at 976 nm.

    Science.gov (United States)

    Kotov, L V; Likhachev, M E; Bubnov, M M; Medvedkov, O I; Yashkov, M V; Guryanov, A N; Lhermite, J; Février, S; Cormier, E

    2013-07-01

    Optimization of Yb-free Er-doped fiber for lasers and amplifiers cladding pumped at 976 nm was performed in this Letter. The single-mode fiber design includes an increased core diameter of 34 μm and properly chosen erbium and co-dopant concentrations. We demonstrate an all-fiber high power laser and power amplifier based on this fiber with the record slope efficiency of 40%. To the best of our knowledge, the achieved output power of 75 W is the highest power reported for such lasers.

  14. High-power Yb-doped continuous-wave and pulsed fibre lasers

    Indian Academy of Sciences (India)

    2014-01-05

    Jan 5, 2014 ... In this article, a review of Yb-doped CW and pulsed fibre lasers along with our study on self-pulsing dynamics in CW fibre lasers to find its role in high-power fibre laser development and the physical ... Solid State Laser Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, India ...

  15. Thermal effects from modified endodontic laser tips used in the apical third of root canals with erbium-doped yttrium aluminium garnet and erbium, chromium-doped yttrium scandium gallium garnet lasers.

    Science.gov (United States)

    George, Roy; Walsh, Laurence J

    2010-04-01

    To evaluate the temperature changes occurring on the apical third of root surfaces when erbium-doped yttrium aluminium garnet (Er:YAG) and erbium, chromium-doped yttrium scandium gallium garnet (Er,Cr:YSGG) laser energy was delivered with a tube etched, laterally emitting conical tip and a conventional bare design optical fiber tip. Thermal effects of root canal laser treatments on periodontal ligament cells and alveolar bone are of concern in terms of safety. A total of 64 single-rooted extracted teeth were prepared 1 mm short of the working length using rotary nickel-titanium Pro-Taper files to an apical size corresponding to a F5 Pro-Taper instrument. A thermocouple located 2 mm from the apex was used to record temperature changes arising from delivery of laser energy through laterally emitting conical tips or plain tips, using an Er:YAG or Er,Cr:YSGG laser. For the Er:YAG and Er,Cr:YSGG systems, conical fibers showed greater lateral emissions (452 + 69% and 443 + 64%) and corresponding lower forward emissions (48 + 5% and 49 + 5%) than conventional plain-fiber tips. All four combinations of laser system and fiber design elicited temperature increases less than 2.5 degrees C during lasing. The use of water irrigation attenuated completely the thermal effects of individual lasing cycles. Laterally emitting conical fiber tips can be used safely under defined conditions for intracanal irradiation without harmful thermal effects on the periodontal apparatus.

  16. Multimode laser emission from dye-doped hollow polymer optical fibre

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Dye-doped polymer optical fibre preforms were fabricated by the controlled polymeriza- tion of Rh B-doped methyl methacrylate (MMA). Hole in the preform can be achieved by placing a teflon rod on the centre of the glass tube during the polymerization. Final fibre structure with required diameter was ...

  17. Influence of the radiation type on properties of silicon doped by erbium

    International Nuclear Information System (INIS)

    Nazyrov, D.E.

    2006-01-01

    Full text: It is known that on effectiveness of formation and kinetics of annealing of radiation damages presence causing, uncontrollable electrical of fissile or inactive impurities, the concentration and position in a lattice of the semiconductor strongly influence. From this point of view, the impurities of group of rare earths elements (REE) represent major interest, since interacting with primary radiation imperfections they create electrical passive complexes such as 'impurity + defect', thus raising radiation stability of silicon. The purpose of sectional operation was the investigations of influence such as radiation exposures: in γ-quanta 60 Co and high-velocity electrons with an energy 3,5 MeV on properties of silicon doped REE-erbium. The doping of silicon REE was carried out during cultivation. The concentration REE in silicon, on sectional of a neutron-activation analysis was equaled 10 14 10 18 cm -3 . As control is model the monocrystalline silicon such as KEP-15 50 was investigation. The experimental outcomes are obtained through methods DLTS, IRC, and also at examination of a Hall effect and conductance is model, measuring of concentration optically active of centers of oxygen and carbon. In samples irradiated in the γ-quanta 60 Co in an interval of doses 10 16 -5·10 18 cm -2 and high-velocity electrons from 5·10 13 up to 10 18 el.·cm -2 the formation various DL in a forbidden region is revealed, which parameters are well-known A- and, E-centres etc. Depending on a radiation dose in an energy distribution of radiation imperfections in Si of essential concentration modifications is not observed. The comparison doses of associations detected DL in irradiated n-Si with similar associations in control samples shows, that a velocity of introduction of radiation imperfections (A- and E-centres) and imperfection with a deep level Ec-0,32 eV) in samples containing REE much lower, than in control samples. The lifetime of non-equilibrium charge carriers

  18. Self-Q-switched ytterbium-doped cladding-pumped fibre laser

    International Nuclear Information System (INIS)

    Grukh, Dmitrii A; Kurkov, Andrei S; Razdobreev, I M; Fotiadi, A A

    2002-01-01

    A self-Q-switched ytterbium-doped double-clad fibre laser is described. A samarium-doped fibre is used as a filter for protecting a pump source. A fibre coupler is employed to obtain a nonlinear feedback. The mechanism of pulse formation in the laser is considered, and the dependence of its output pulse on the coupler parameters is studied. (solitons and optical fibers)

  19. A Filmy Black-Phosphorus Polyimide Saturable Absorber for Q-Switched Operation in an Erbium-Doped Fiber Laser

    Directory of Open Access Journals (Sweden)

    Tianxian Feng

    2016-11-01

    Full Text Available We demonstrate an erbium-doped fiber laser passively Q-switched by a black-phosphorus polyimide film. The multi-layer black-phosphorus (BP nanosheets were prepared via a liquid exfoliation approach exploiting N-methylpyrrolidone as the dispersion liquid. By mixing the BP nanosheets with polyimide (PI, a piece of BP–PI film was obtained after evaporating the mixture in a petri dish. The BP–PI saturable absorber had a modulation depth of 0.47% and was inserted into an erbium-doped fiber laser to realize passive Q-switched operations. The repetition rate of the Q-switched laser increased from 5.73 kHz to 31.07 kHz when the laser pump was enhanced from 31.78 mW to 231.46 mW. Our results show that PI is an excellent host material to protect BP from oxidation, and the BP–PI film can act as a promising nonlinear optical device for laser applications.

  20. Stable single longitudinal mode erbium-doped silica fiber laser based on an asymmetric linear three-cavity structure

    International Nuclear Information System (INIS)

    Feng Ting; Yan Feng-Ping; Li Qi; Peng Wan-Jing; Feng Su-Chun; Tan Si-Yu; Wen Xiao-Dong

    2013-01-01

    We present a stable linear-cavity single longitudinal mode (SLM) erbium-doped silica fiber laser. It consists of four fiber Bragg gratings (FBGs) directly written in a section of photosensitive erbium-doped fiber (EDF) to form an asymmetric three-cavity structure. The stable SLM operation at a wavelength of 1545.112 nm with a 3-dB bandwidth of 0.012 nm and an optical signal-to-noise ratio (OSNR) of about 60 dB is verified experimentally. Under laboratory conditions, the performance of a power fluctuation of less than 0.05 dB observed from the power meter for 6 h and a wavelength variation of less than 0.01 nm obtained from the optical spectrum analyzer (OSA) for about 1.5 h are demonstrated. The gain fiber length is no longer limited to only several centimeters for SLM operation because of the excellent mode-selecting ability of the asymmetric three-cavity structure. The proposed scheme provides a simple and cost-effective approach to realizing a stable SLM fiber laser. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  1. A stable wavelength-tunable single frequency and single polarization linear cavity erbium-doped fiber laser

    International Nuclear Information System (INIS)

    Feng, T; Yan, F P; Li, Q; Peng, W J; Tan, S Y; Feng, S C; Wen, X D; Liu, P

    2013-01-01

    We report the configuration and operation of a wavelength-tunable single frequency and single polarization erbium-doped fiber laser (EDFL) with a stable and high optical signal to noise ratio (OSNR) laser output. A narrow-band fiber Bragg grating (NBFBG), a FBG-based Fabry–Perot (FP) filter, a polarization controller (PC) and an unpumped erbium-doped fiber (EDF) as a saturable absorber (SA) are employed to realize stable single frequency lasing operation. An all-fiber polarizer (AFP) is introduced to suppress mode hopping and ensure the single polarization mode operation. By adjusting the length of the NBFBG using a stress adjustment module (SAM), four stable single frequency and single polarization laser outputs at wavelengths of 1544.946, 1545.038, 1545.118 and 1545.182 nm are obtained. At room temperature, performance with an OSNR of larger than 60 dB, power fluctuation of less than 0.04 dB, wavelength variation of less than 0.01 nm for about 5 h measurement, and degree of polarization (DOP) of close to 100% has been experimentally demonstrated for the fiber laser operating at these four wavelengths. (paper)

  2. Optical properties of PMMA doped with erbium(III) and ytterbium(III) complexes

    Czech Academy of Sciences Publication Activity Database

    Prajzler, V.; Huttel, I.; Lyutakov, O.; Oswald, Jiří; Machovič, V.; Jerabek, V.

    2009-01-01

    Roč. 49, č. 9 (2009), s. 1814-1817 ISSN 0032-3888 Institutional research plan: CEZ:AV0Z10100521 Keywords : polymers * erbium * photoluminescence Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.248, year: 2009

  3. Erbium medium temperature localised doping into lithium niobate and sapphire: A comparative study

    Czech Academy of Sciences Publication Activity Database

    Nekvindová, P.; Macková, Anna; Peřina, Vratislav; Červená, Jarmila; Čapek, P.; Schrofel, J.; Špirková, J.; Oswald, Jiří

    90-91, - (2003), s. 559-564 ISSN 1012-0394 Institutional research plan: CEZ:AV0Z1048901 Keywords : lithium niobate * sapphire * erbium Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.687, year: 2003

  4. Transverse UV-laser irradiation-induced defects and absorption in a single-mode erbium-doped optical fiber

    International Nuclear Information System (INIS)

    Tortech, B.; Ouerdane, Y.; Boukenter, A.; Meunier, J. P.; Girard, S.; Van Uffelen, M.; Berghmans, F.; Regnier, E.; Berghmans, F.; Thienpont, H.

    2009-01-01

    Near UV-visible absorption coefficients of an erbium-doped optical fiber were investigated through an original technique based on a transverse cw UV-laser irradiation operating at 244 nm. Such irradiation leads to the generation of a quite intense guided luminescence signal in near UV spectral range. This photoluminescence probe source combined with a longitudinal translation of the fiber sample (at a constant velocity) along the UV-laser irradiation, presents several major advantages: (i) we bypass and avoid the procedures classically used to study the radiation induced attenuation which are not adapted to our case mainly because the samples present a very strong absorption with significant difficulties due to the injection of adequate UV-light levels in a small fiber diameter: (ii) the influence of the laser irradiation on the host matrix of the optical fiber is directly correlated to the evolution of the generated photoluminescence signal and (iii) in our experimental conditions, short fiber sample lengths (typically 20-30 cm) suffice to determine the associated absorption coefficients over the entire studied spectral domain. The generated photoluminescence signal is also used to characterize the absorption of the erbium ions in the same wavelength range with no cut-back method needed. (authors)

  5. A nonuniform-polarization high-energy ultra-broadband laser with a long erbium-doped fiber

    International Nuclear Information System (INIS)

    Mao, Dong

    2013-01-01

    We have experimentally investigated nonuniformly polarized broadband high-energy pulses delivered from a mode-locked laser with an ultra-long erbium-doped fiber (EDF). The pulses exhibit a broadband spectrum of ∼73 nm and can avoid optical wave breaking at high-pump regimes. The polarization states of the pulses evolve from uniform to nonuniform at each round trip in the oscillator, which is distinct from other pulses. Remarkably, the output pulses broaden in anomalous- or normal-dispersion regimes while they can be shortened with an EDF amplifier external to the cavity. Our results suggest that the long EDF results in a nonuniform-polarization state and plays a decisive role in the formation of high-energy pulses. (paper)

  6. Femtosecond laser direct writing of gratings and waveguides in high quantum efficiency erbium-doped Baccarat glass

    International Nuclear Information System (INIS)

    Vishnubhatla, K C; Kumar, R Sai Santosh; Rao, D Narayana; Rao, S Venugopal; Osellame, R; Ramponi, R; Bhaktha, S N B; Mattarelli, M; Montagna, M; Turrell, S; Chiappini, A; Chiasera, A; Ferrari, M; Righini, G C

    2009-01-01

    The femtosecond laser direct writing technique was employed to inscribe gratings and waveguides in high quantum efficiency erbium-doped Baccarat glass. Using the butt coupling technique, a systematic study of waveguide loss with respect to input pulse energy and writing speed was performed to achieve the best waveguide with low propagation loss (PL). By pumping at 980 nm, we observed signal enhancement in these active waveguides in the telecom spectral region. The refractive index change was smooth and we estimated it to be ∼10 -3 . The high quantum efficiency (∼80%) and a best PL of ∼0.9 dB cm -1 combined with signal enhancement makes Baccarat glass a potential candidate for application in photonics.

  7. Rare-Earth Doped Photonic Crystal Fibre Lasers and Amplifiers

    DEFF Research Database (Denmark)

    Hougaard, Kristian G.

    2005-01-01

    In this thesis, a theoretical and numerical study of the use of rare-earthdoped photonic crystal fibres as optical amplifiers and lasers, has been performed. Photonic crystal fibres or microstructured optical fibres is a new kind of optical fibre in which the cladding region typically consist....... Their novel properties allow for design of optical fibre amplifiers and fibre lasers with superior performance, compared to solutions based on conventional fibres. The primary applications considered are high efficiency fibre amplifiers based on index guiding photonic crystal fibres, and cladding pumped....... The thesis also presents the basic properties of optical amplification, and describes the numerical model developed to model the behaviour of lasers and amplifiers based on photonic crystal fibres. The developed numerical tools are then used to investigate specific applications of photonic crystal fibres...

  8. Thulium-doped fibre broadband source for spectral region near 2 micrometers

    Czech Academy of Sciences Publication Activity Database

    Písařík, Michael; Peterka, P.; Aubrecht, J.; Cajzl, J.; Benda, A.; Mareš, D.; Todorov, F.; Podrazký, O.; Honzatko, P.; Kašík, I.

    2016-01-01

    Roč. 24, č. 4 (2016), s. 223-231 ISSN 1230-3402 Institutional support: RVO:68378271 Keywords : fibre lasers * amplified spontaneous emission * thulium-doped fibres Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 1.449, year: 2016

  9. Erbium/ytterbium co-doped double clad fiber amplifier, its applications and effects in fiber optic communication systems

    Science.gov (United States)

    Dua, Puneit

    Increased demand for larger bandwidth and longer inter-amplifiers distances translates to higher power budgets for fiber optic communication systems in order to overcome large splitting losses and achieve acceptable signal-to-noise ratios. Due to their unique design ytterbium sensitized erbium doped, double clad fiber amplifiers; offer significant increase in the output powers that can be obtained. In this thesis we investigate, a one-stage, high power erbium and ytterbium co-doped double clad fiber amplifier (DCFA) with output power of 1.4W, designed and built in our lab. Experimental demonstration and numerical simulation techniques have been used to systematically study the applications of such an amplifier and the effects of incorporating it in various fiber optic communication systems. Amplitude modulated subcarrier multiplexed (AM-SCM) CATV distribution experiment has been performed to verify the feasibility of using this amplifier in an analog/digital communication system. The applications of the amplifier as a Fabry-Perot and ring fiber laser with an all-fiber cavity, a broadband supercontinuum source and for generation of high power, short pulses at 5GHz have been experimentally demonstrated. A variety of observable nonlinear effects occur due to the high intensity of the optical powers confined in micron-sized cores of the fibers, this thesis explores in detail some of these effects caused by using the high power Er/Yb double clad fiber amplifier. A fiber optic based analog/digital CATV system experiences composite second order (CSO) distortion due to the interaction between the gain tilt---the variation of gain with wavelength, of the doped fiber amplifier and the wavelength chirp of the directly modulated semiconductor laser. Gain tilt of the Er/Yb co-doped fiber amplifier has been experimentally measured and its contribution to the CSO of the system calculated. Theoretical analysis of a wavelength division multiplexed system with closely spaced

  10. Effects of time-temperature profiles on glow curves of germanium-doped optical fibre

    Science.gov (United States)

    Lam, S. E.; Alawiah, A.; Bradley, D. A.; Mohd Noor, N.

    2017-08-01

    The Germanium (Ge) doped silica optical fibres have demonstrated the great potential to be developed as a thermoluminescent (TL) dosimeter that can be used in various applications in radiotherapy, diagnostic radiology, UV dosimetry system and food irradiation industry. Different time-temperature profile (TTP) parameters of the TL reader have been employed by many researchers in various of TL studies. Nevertheless, none of those studies adequately addressed the effects of the reader's preheat temperature and heating rate on the kinetic parameters of the TL glow curve specifically, the Ge-doped silica optical fibres. This research addresses the issue of TTP parameters with special attention to the determination of the kinetic parameters of the glow curve. The glow curve responses were explored and the kinetic parameters were analyzed by the WinGCF software, to show the effect of the preheat temperature and heating rate of the reader on Ge-doped fibre irradiated with 18 Gy of 6 MV photons radiation. The effect of TTP parameters was discussed and compared against the commercial fibre and tailored made fibre of 6 mol% Ge-doped of flat and cylindrical shape. The deconvolution of glow peaks and the kinetic parameters were obtained by the WinGCF software. This enables to fit accurately (1.5%fibre (50 °C) and cylindrical fibre (80 °C and 160 °C). It is found that the glow peaks of cylindrical fibre exhibit the highest peak integral as compared to flat and commercial fibres. This study revealed the possible relationship between the reader's TTP parameters and the kinetic parameters of TL glow curves for the commercial and tailored made Ge-doped silica optical fibres.

  11. Study of the use of methanol-filled Er-doped suspended-core fibres in a temperature-sensing ring laser system

    International Nuclear Information System (INIS)

    Martín, J C; Berdejo, V; Vallés, J A; Sánchez-Martín, J A; Díez, A; Andrés, M V

    2013-01-01

    We report on an experimental/numerical investigation into the use of methanol-filled Er-doped suspended-core fibres (SCFs) in temperature-sensing ring laser systems. We have adopted a ring laser configuration that includes an Er-doped SCF as a temperature-dependent attenuator (TDA) with a step-index Er-doped fibre (EDF) as the laser active medium. The laser performance dependence on the temperature was measured both in continuous wave (CW) and transient regimes. CW laser output power and build-up time values are compared with those of similar laser systems based on other types of Er-doped PCFs or using other laser configurations. A notable variation of 0.73% °C −1 was achieved in CW operation. Then, by means of parameters obtained by numerically fitting the experimental results, the potential sensing performance of the laser configuration with an SCF as a TDA is studied. Moreover, two ring cavity laser configurations (with the SCF acting basically as an attenuator or also as the active media) are compared and the influence of the position of the coupler inside the ring cavity and the contribution of the erbium doping to improve the sensor features are analysed. The longer interaction lengths compatible with laser action using the Er-doped SCF as a TDA could provide variations of laser output power up to 8.6% °C −1 for 90 mW pump power and a 1 m methanol-filled SCF. (paper)

  12. 1.54 μm Er3+ electroluminescence from an erbium-compound-doped organic light emitting diode with a p-type silicon anode

    International Nuclear Information System (INIS)

    Zhao, W Q; Wang, P F; Ran, G Z; Ma, G L; Zhang, B R; Liu, W M; Wu, S K; Dai, L; Qin, G G

    2006-01-01

    By doping an erbium complex, erbium (III) 2, 4-pentanedionate (Er(acac) 3 ), into the ALQ layer, we fabricate a series of infrared emission organic light emitting diodes (OLED) with structures of p-Si/SiO 2 /NPB/ALQ/ ALQ:Er(acac) 3 /ALQ/Sm/Au, where p-Si is the anode and Sm/Au is the cathode. The 1.54 μm emission from Er 3+ is observed. The impact of doping level of Er(acac) 3 in ALQ on 1.54 μm electroluminescence (EL) intensity is studied, and the best mass ratio of Er(acac) 3 to ALQ is found at 1:60. A competitive EL mechanism from the ALQ and Er(acac) 3 is found and the Er 3+ ions excitations are attributed to energy transfer from the ligands to Er ions

  13. Tunable single-polarization single-longitudinal-mode erbium-doped fiber ring laser employing a CMFBG filter and saturable absorber

    Science.gov (United States)

    Feng, Suchun; Lu, Shaohua; Peng, Wanjing; Li, Qi; Feng, Ting; Jian, Shuisheng

    2013-04-01

    A tunable single-polarization single-longitudinal-mode (SLM) erbium-doped fiber ring laser is proposed and demonstrated. For the first time as we know, a chirped moiré fiber Bragg grating (CMFBG) filter with ultra-narrow transmission band and a uniform fiber Bragg grating (UFBG) are used to select the laser longitudinal mode. The stable SLM operation of the fiber laser is guaranteed by the combination of the CMFBG filter and 3 m unpumped erbium-doped fiber acting as a saturable absorber. The single polarization operation of the fiber laser is obtained by using an inline broadband polarizer. A tuning range of about 0.7 nm with about 0.1 nm step is achieved by stretching the uniform FBG.

  14. The thermoluminescence response of Ge-doped flat fibre for proton beam measurements: A preliminary study

    International Nuclear Information System (INIS)

    Hassan, M F; Fadzil, M S Ahmad; Noor, N Mohd; Abdul Rahman, W N Wan; Tominaga, T; Geso, M; Akasaka, H; Bradley, D A

    2017-01-01

    The aim of this study was to investigate the thermoluminescence (TL) response of fabricated 2.3 mol% and 6.0 mol% germanium (Ge) doped flat optical fibres to proton irradiation. The fundamental dosimetric characteristics of the fibres have been investigated including dose linearity, reproducibility and fading. The thermoluminescent dosimeters (TLDs) were used as a reference dosimeter to allow the relative response of the fibres. The results show that Ge-doped flat fibres offer excellent dose linearity over the dose range from 1 Gy up to 10 Gy with correlation of determination (R 2 ) of 0.99. The fibres also demonstrated good reproducibility within the standard deviation (SD) of 0.86% to 6.41%. After 96 days post-irradiation, TLD-100 chips gave rise to the least loss in TL signal at around 18% followed by fabricated 2.3 mol% Ge-doped flat fibres about 24%. This preliminary study has demonstrated that the proposed fabricated Ge-doped flat fibre offers a promising potential for use in proton beam measurements. (paper)

  15. Q-switched Erbium-doped fiber laser at 1600 nm for photoacoustic imaging application

    Energy Technology Data Exchange (ETDEWEB)

    Piao, Zhonglie [Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Beckman Laser Institute, Department of Biomedical Engineering, University of California, Irvine, California 92612 (United States); Zeng, Lvming; Chen, Zhongping, E-mail: z2chen@uci.edu, E-mail: ckim@pusan.ac.kr [Beckman Laser Institute, Department of Biomedical Engineering, University of California, Irvine, California 92612 (United States); Kim, Chang-Seok, E-mail: z2chen@uci.edu, E-mail: ckim@pusan.ac.kr [Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2016-04-04

    We present a nanosecond Q-switched Erbium-doped fiber (EDF) laser system operating at 1600 nm with a tunable repetition rate from 100 kHz to 1 MHz. A compact fiber coupled, acousto-optic modulator-based EDF ring cavity was used to generate a nanosecond seed laser at 1600 nm, and a double-cladding EDF based power amplifier was applied to achieve the maximum average power of 250 mW. In addition, 12 ns laser pulses with the maximum pulse energy of 2.4 μJ were obtained at 100 kHz. Furthermore, the Stokes shift by Raman scattering over a 25 km long fiber was measured, indicating that the laser can be potentially used to generate the high repetition rate pulses at the 1.7 μm region. Finally, we detected the photoacoustic signal from a human hair at 200 kHz repetition rate with a pulse energy of 1.2 μJ, which demonstrates that a Q-switched Er-doped fiber laser can be a promising light source for the high speed functional photoacoustic imaging.

  16. Spectroscopic Properties of Neodymium and Erbium-Doped Magnesium Oxide Ceramics

    Science.gov (United States)

    2015-09-01

    universally >99% of theoretical. Powder x-ray diffraction (XRD) analysis was employed to determine the crystalline phases in doped MgO ceramics after the...different sintering steps. Powders of sintered pellets were prepared by grinding fragments in a glass mortar and pestle to avoid crystalline...than anticipated for the doped MgO. Somewhat more conclusive information on the extent of successful RE doping was derived from the XRD analysis

  17. Erbium–ytterbium fibre laser emitting more than 13 W of power in ...

    Indian Academy of Sciences (India)

    2014-01-05

    Jan 5, 2014 ... We report the work on erbium:ytterbium-doped double clad fibre laser (EYDFL), that is pumped at ... reduction in life-time. The active ... region. Figure 2 shows plot of output power vs. absorbed pump power (after accounting.

  18. High power operation of cladding pumped holmium-doped silica fibre lasers.

    Science.gov (United States)

    Hemming, Alexander; Bennetts, Shayne; Simakov, Nikita; Davidson, Alan; Haub, John; Carter, Adrian

    2013-02-25

    We report the highest power operation of a resonantly cladding-pumped, holmium-doped silica fibre laser. The cladding pumped all-glass fibre utilises a fluorine doped glass layer to provide low loss cladding guidance of the 1.95 µm pump radiation. The operation of both single mode and large-mode area fibre lasers was demonstrated, with up to 140 W of output power achieved. A slope efficiency of 59% versus launched pump power was demonstrated. The free running emission was measured to be 2.12-2.15 µm demonstrating the potential of this architecture to address the long wavelength operation of silica based fibre lasers with high efficiency.

  19. Nonlinear Polarization Rotation-Based Mode-Locked Erbium-Doped Fiber Laser with Three Switchable Operation States

    International Nuclear Information System (INIS)

    Tiu Zian Cheak; Tan Sin Jin; Zarei Arman; Ahmad Harith; Harun Sulaiman Wadi

    2014-01-01

    A simple mode-locked erbium-doped fiber laser (EDFL) with three switchable operation states is proposed and demonstrated based on nonlinear polarization rotation. The EDFL generates a stable square pulse at a third harmonic pulse repetition rate of 87 kHz as the 1480 nm pump power increases from the threshold of 17.5 mW to 34.3 mW. The square pulse duration increases from 105 ns to 245 ns as the pump power increases within this region. The pulse operation switches to the second operation state as the pump power is varied from 48.2 mW to 116.7 mW. The laser operates at a fundamental repetition rate of 29 kHz with a fixed pulse width of 8.5 μs within the pump power region. At a pump power of 116.7 mW, the average output power is 3.84 mW, which corresponds to the pulse energy of 131.5 nJ. When the pump power continues to increase, the pulse train experiences unstable oscillation before it reaches the third stable operation state within a pump power region of 138.9 mW to 145.0 mW. Within this region, the EDFL produces a fixed pulse width of 2.8 μs and a harmonic pulse repetition rate of 58 kHz. (fundamental areas of phenomenology(including applications))

  20. Tunable erbium-doped fiber laser based on optical fiber Sagnac interference loop with angle shift spliced polarization maintaining fibers

    Science.gov (United States)

    Ding, Zhenming; Wang, Zhaokun; Zhao, Chunliu; Wang, Dongning

    2018-05-01

    In this paper, we propose and experimentally demonstrate a tunable erbium-doped fiber laser (EDFL) with Sagnac interference loop with 45° angle shift spliced polarization maintaining fibers (PMFs). In the Sagnac loop, two PMFs with similar lengths. The Sagnac loop outputs a relatively complex interference spectrum since two beams transmitted in clockwise and counterclockwise encounter at the 3 dB coupler, interfere, and form two interference combs when the light transmitted in the Sagnac loop. The laser will excite and be stable when two interference lines in these two interference combs overlap together. Then by adjusting the polarization controller, the wide wavelength tuning is realized. Experimental results show that stable single wavelength laser can be realized in the wavelength range of 1585 nm-1604 nm under the pump power 157.1 mW. The side-mode suppression ratio is not less than 53.9 dB. The peak power fluctuation is less than 0.29 dB within 30 min monitor time and the side-mode suppression ratio is great than 57.49 dB when the pump power is to 222.7 mW.

  1. Femtosecond mode-locked erbium-doped fiber laser based on MoS2-PVA saturable absorber

    Science.gov (United States)

    Ahmed, M. H. M.; Latiff, A. A.; Arof, H.; Ahmad, H.; Harun, S. W.

    2016-08-01

    We fabricate a free-standing few-layer molybdenum disulfide (MoS2)-polymer composite by liquid phase exfoliation of chemically pristine MoS2 crystals and use this to demonstrate a soliton mode-locked Erbium-doped fiber laser (EDFL). A stable self-started mode-locked soliton pulse is generated by fine-tuning the rotation of the polarization controller at a low threshold pump power of 25 mW. Its solitonic behavior is verified by the presence of Kelly sidebands in the output spectrum. The central wavelength, pulse width, and repetition rate of the laser are 1573.7 nm, 630 fs, and 27.1 MHz, respectively. The maximum pulse energy is 0.141 nJ with peak power of 210 W at pump power of 170 mW. This result contributes to the growing body of work studying the nonlinear optical properties of transition metal dichalcogenides that present new opportunities for ultrafast photonic applications.

  2. Generation of Q-Switched Mode-Locked Erbium-Doped Fiber Laser Operating in Dark Regime

    International Nuclear Information System (INIS)

    Tiu, Zian Cheak; Zarei, Arman; Ahmad, Harith; Harun, Sulaiman Wadi

    2016-01-01

    We demonstrate a stable Q-switched mode-locked erbium-doped fiber laser (EDFL) operating in dark regime based on the nonlinear polarization rotation technique. The EDFL produces a pulse train where the Q-switching envelope is formed by multiple dark pulses. The repetition rate of the Q-switched envelope can be increased from 0.96 kHz to 3.26 kHz, whereas the pulse width reduces from 211 μs to 86 μs. The highest pulse of 479 nJ is obtained at the pump power of 55 mW. It is also observed that the dark pulses inside the Q-switching envelope consist of two parts: square and trailing dark pulses. The shortest pulse width of the dark square pulse is obtained at 40.5 μs when the pump power is fixed at 145 mW. The repetition rate of trailing dark pulses can be increased from 27.62 kHz to 50 kHz as the pump power increases from 55 mW to 145 mW. (paper)

  3. Fractional erbium-doped yttrium aluminum garnet laser-assisted drug delivery of hydroquinone in the treatment of melasma

    Science.gov (United States)

    Badawi, Ashraf M; Osman, Mai Abdelraouf

    2018-01-01

    Background Melasma is a difficult-to-treat hyperpigmentary disorder. Ablative fractional laser (AFL)-assisted delivery of topically applied drugs to varied targets in the skin has been an area of ongoing study and research. Objective The objective of this study was to evaluate the efficacy and safety of fractional erbium-doped yttrium aluminum garnet (Er:YAG) laser as an assisted drug delivery for enhancing topical hydroquinone (HQ) permeation into the skin of melasma patients. Patients and methods Thirty female patients with bilateral melasma were randomly treated in a split-face controlled manner with a fractional Er:YAG laser followed by 4% HQ cream on one side and 4% HQ cream alone on the other side. All patients received six laser sessions with a 2-week interval. The efficacy of treatments was determined through photographs, dermoscopic photomicrographs and Melasma Area Severity Index (MASI) score, all performed at baseline and at 12 weeks of starting therapy. The patient’s level of satisfaction was also recorded. Results Er:YAG laser + HQ showed significantly better results (plaser + HQ side vs HQ side. Minor reversible side effects were observed on both sides. Conclusion AFL-assisted delivery of HQ is a safe and effective method for the treatment of melasma. PMID:29379308

  4. Thulium-doped fibre broadband source for spectral region near 2 micrometers

    Czech Academy of Sciences Publication Activity Database

    Písařík, M.; Peterka, Pavel; Aubrecht, Jan; Cajzl, Jakub; Benda, Adam; Mareš, D.; Todorov, Filip; Podrazký, Ondřej; Honzátko, Pavel; Kašík, Ivan

    2016-01-01

    Roč. 24, č. 4 (2016), s. 223-231 ISSN 1230-3402 R&D Projects: GA MZd(CZ) NV15-33459A Institutional support: RVO:67985882 ; RVO:68378271 Keywords : fibre lasers * amplified spontaneous emission * thulium-doped fibres Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 1.449, year: 2016

  5. Performance of Erbium-doped TiO2 thin film grown by physical vapor deposition technique

    Science.gov (United States)

    Lahiri, Rini; Ghosh, Anupam; Dwivedi, Shyam Murli Manohar Dhar; Chakrabartty, Shubhro; Chinnamuthu, P.; Mondal, Aniruddha

    2017-09-01

    Undoped and Erbium-doped TiO2 thin films (Er:TiO2 TFs) were fabricated on the n-type Si substrate using physical vapour deposition technique. Field emission scanning electron microscope showed the morphological change in the structure of Er:TiO2 TF as compared to undoped sample. Energy dispersive X-ray spectroscopy (EDX) confirmed the Er doping in the TiO2 thin film (TF). The XRD and Raman spectrum showed the presence of anatase phase TiO2 and Er2O3 in the Er:TiO2 TF. The Raman scattering depicted additional number of vibrational modes for Er:TiO2 TF due to the presence of Er as compared to the undoped TiO2 TF. The UV-Vis absorption measurement showed that Er:TiO2 TF had approximately 1.2 times more absorption over the undoped TiO2 TF in the range of 300-400 nm. The main band transition, i.e., the transition between the oxygen (2p) state and the Ti (3d) state was obtained at 3.0 eV for undoped TiO2 and at 3.2 eV for Er:TiO2 TF, respectively. The photo responsivity measurement was done on both the detectors, where Er:TiO2 TF detector showed better detectivity ( D *), noise equivalent power and temporal response as compared to undoped detector under ultra-violet illumination.

  6. Combined up conversion, down conversion and down shifting photo-luminescence of low cost erbium-ytterbium co-doped porous silicon produced by stain etching

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Herrera, B. [Departamento de Fisica Basica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez, 2, 38206 La Laguna, S/C de Tenerife (Spain); Linsun Power Technology (Quanzhou) Corp. Ltd. Co., Economic Development Zone, Jinjiang 362200, Fujian (China); Jimenez-Rodriguez, E. [Departamento de Fisica Basica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez, 2, 38206 La Laguna, S/C de Tenerife (Spain); Gonzalez-Diaz, B. [Departamento de Fisica Basica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez, 2, 38206 La Laguna, S/C de Tenerife (Spain); Instituto Tecnologico y de Energias Renovables, S.A. (ITER), Poligono Industrial de Granadilla, S/N, E38600, Granadilla de Abona (Spain); Montesdeoca-Santana, A. [Departamento de Fisica Basica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez, 2, 38206 La Laguna, S/C de Tenerife (Spain); Velazquez, J.J. [Departamento de Fisica Fundamental y Experimental, Electronica y Sistemas, Avenida Astrofisico Francisco Sanchez, 2, 38206 La Laguna, S/C de Tenerife (Spain); Guerrero-Lemus, R., E-mail: rglemus@ull.es [Departamento de Fisica Basica, Universidad de La Laguna (ULL), Avenida Astrofisico Francisco Sanchez, 2, 38206 La Laguna, S/C de Tenerife (Spain); Fundacion de Estudios de Economia Aplicada, Programa Focus-Abengoa de Energia y Cambio Climaticoi, Jorge Juan 46, 28001 Madrid (Spain)

    2011-07-01

    In this work, erbium and ytterbium have been incorporated into luminescent porous silicon (PS) layers by simple impregnation of the PS substrate with a saturated nitrate solution of erbium and ytterbium. The photoluminescence of the co-doped rare earth layers have been evaluated. The doping process has been designed for its potential in silicon-based solar cell production, with the aim to improve the Shockley-Queisser limit with a reasonable cost effective method for the industry, which implies a significant enhancement of the efficiency under non-concentrated sunlight irradiation. The temperature and annealing time of the doping process were selected according to industry standards in order to ease a trial adoption. The composition was analyzed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy in order to characterize the doping profile. Different up-conversion and down-conversion contributions from the rare earths in the visible and IR were detected, together with the down shifting effect of the stain etched PS. There is no evidence of energy transference between the PS matrix and the rare earths.

  7. Structural Modification of Sol-Gel Synthesized V2O5 and TiO2 Thin Films with/without Erbium Doping

    Directory of Open Access Journals (Sweden)

    Fatma Pınar Gökdemir

    2014-01-01

    Full Text Available Comparative work of with/without erbium- (Er- doped vanadium pentoxide (V2O5 and titanium dioxide (TiO2 thin films were carried out via sol-gel technique by dissolving erbium (III nitrate pentahydrate (Er(NO33·5H2O in vanadium (V oxoisopropoxide (OV[OCH(CH32]3 and titanium (IV isopropoxide (Ti[OCH(CH32]4. Effect of Er doping was traced by Fourier transform IR (FTIR, thermogravimetric/differential thermal (TG/DTA, and photoluminescence measurements. UV-Vis transmission/absorption measurement indicated a blue shift upon Er doping in V2O5 film due to the softening of V=O bond while appearance of typical absorption peaks in Er-doped TiO2 film. Granule size of the films increased (reduced upon Er substitution on host material compared to undoped V2O5 and TiO2 films, respectively.

  8. Combined up conversion, down conversion and down shifting photo-luminescence of low cost erbium-ytterbium co-doped porous silicon produced by stain etching

    International Nuclear Information System (INIS)

    Diaz-Herrera, B.; Jimenez-Rodriguez, E.; Gonzalez-Diaz, B.; Montesdeoca-Santana, A.; Velazquez, J.J.; Guerrero-Lemus, R.

    2011-01-01

    In this work, erbium and ytterbium have been incorporated into luminescent porous silicon (PS) layers by simple impregnation of the PS substrate with a saturated nitrate solution of erbium and ytterbium. The photoluminescence of the co-doped rare earth layers have been evaluated. The doping process has been designed for its potential in silicon-based solar cell production, with the aim to improve the Shockley-Queisser limit with a reasonable cost effective method for the industry, which implies a significant enhancement of the efficiency under non-concentrated sunlight irradiation. The temperature and annealing time of the doping process were selected according to industry standards in order to ease a trial adoption. The composition was analyzed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy in order to characterize the doping profile. Different up-conversion and down-conversion contributions from the rare earths in the visible and IR were detected, together with the down shifting effect of the stain etched PS. There is no evidence of energy transference between the PS matrix and the rare earths.

  9. Characterization of Ge-doped optical fibres for MV radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Noor, Noramaliza M.; Hussein, M.; Kadni, T.; Bradley, D.A.; Nisbet, A.

    2014-01-01

    Ge-doped optical fibres offer promising thermoluminescence (TL) properties together with small physical size and modest cost. Their use as dosimeters for postal radiotherapy dose audits of megavoltage photon beams has been investigated. Key dosimetric characteristics including reproducibility, linearity, dose rate, temperature and angular dependence have been established. A methodology of measuring absorbed dose under reference conditions was developed. The Ge-doped optical fibres offer linearity between TL yield and dose, with a reproducibility of better than 5%, following repeated measurements (n=5) for doses from 5 cGy to 1000 cGy. The fibres also offer dose rate, angular and temperature independence, while an energy-dependent response of 7% was found over the energy range 6 MV to 15 MV (TPR 20,10 of 0.660, 0.723 and 0.774 for 6, 10 and 15 MV respectively). The audit methodology has been developed with an expanded uncertainty of 4.22% at 95% confidence interval for the photon beams studied. - Highlights: • We investigate dosimetric characteristics of commercial Ge-doped optical fibres. • We develop audit methodology for measuring absorbed dose under reference conditions. • Ge-doped optical fibres offer promising thermoluminescence (TL) properties. • Audit methodology has been developed with an expanded uncertainty of 4.22%

  10. Photon Irradiation Response on Ge and Al-Doped SiO2 Optical Fibres

    Science.gov (United States)

    Yaakob, Nor Haliza; Wagiran, Husin; Ramli, Ahmad Termizi; Ali, Hassan; Asni, Hazila

    2010-07-01

    Recently, research groups have reported a number of radiation effects on the applications of SiO2 optical fibres with possible use as dosimeter material because these optical fibre provide a good basis for medical radiation dosimetry. The objective of this study is to investigate the thermoluminescence response and fading characteristic for germanium and aluminium doped SiO2 optical fibres with photon irradiation. These optical fibres are placed in solid phantom and irradiated to 6 and 10 MV photon beam at dose ranging from 0.06 Gy to 0.24 Gy using Primus MLC 3339 linear accelerator at Hospital Sultan Ismail, Johor Bahru. In fading studies, the TL measurements were continued up to 14 days period. The optical fibres will produce glow curves whereby the information is then analyzed. Al and Ge-doped optical fibres have a linear dose-TL signal relationship that is proportionality between the TL signal and the doses. Comparison for TL response between different linear accelerator showed a good agreement because these optical fibres also have a linear dose-TL signal relationship even using different equipments.

  11. Properties of RF magnetron sputtered gallium nitride semiconductors doped with erbium

    Czech Academy of Sciences Publication Activity Database

    Peřina, Vratislav; Macková, Anna; Hnatowicz, Vladimír; Prajzler, V.; Machovič, V.; Matějka, P.; Schröfel, J.

    2004-01-01

    Roč. 36, č. 8 (2004), s. 952-954 ISSN 0142-2421 R&D Projects: GA ČR GA104/03/0387 Institutional research plan: CEZ:AV0Z1048901 Keywords : Er-doped GaN * luminescence * magnetron sputtering Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.209, year: 2004

  12. Optical signal inverter of erbium-doped yttrium aluminum garnet with red shift of laser diodes.

    Science.gov (United States)

    Maeda, Y

    1994-08-10

    An optical signal inverter was demonstrated in a simple structure that combined a laser diode with Er-doped YAG crystal. The optical signal inversion occurred at a response time of 7 ns and was caused by the decrease of transmission of Er:YAG against the red shift of the wavelength of the laser diode.

  13. Femtosecond pulse generation and amplification in Yb-doped fibre ...

    Indian Academy of Sciences (India)

    remained a challenge as it requires the careful optimization of dispersion, nonlinearity, gain and ASE ... power is obtained from the fibre oscillator–amplifier system at a repetition rate of 43 ..... ing to 53% optical-to-optical conversion efficiency.

  14. Influence of dose history on thermoluminescence response of Ge-doped silica optical fibre dosimeters

    International Nuclear Information System (INIS)

    Moradi, F.; Mahdiraji, G.A.; Dermosesian, E.; Khandaker, M.U.; Ung, N.M.; Mahamd Adikan, F.R.; Amin, Y.M.

    2017-01-01

    Nowadays, silica based optical fibres show enough potential to be used as TL dosimeters in different applications. Reuse of optical fibre as a practical dosimeter demands to complete removal of accumulated doses via previous irradiations. This work investigates the existence and/or effect of remnant doses in fibre dosimeter from the previous irradiations, and proposes a method to control this artifact. A single mode Ge-doped optical fibre is used as TL radiation sensor, while a well calibrated Gammacell with 60 Co source is used for irradiations. The effect of irradiation history on the TL response of optical fibres is surveyed extensively for doses ranged from 1 to 1000 Gy. The results show that the absorbed dose history in a fibre affects its response in the next irradiation cycles. It is shown that a dose history of around 100 Gy can increase the response of optical fibre by a factor of 1.72. The effect of annealing at higher temperatures on stabilizing the fibre response is also examined and results revealed that another alteration in the structure of trapping states occurs in glass medium which can change the sensitivity of fibres. Preservation of the sensitivity during successive irradiation cycles can be achieved by a proper annealing procedure accompanied by a pre-dose treatment. - Highlights: • Influence of dose history on TL characteristics of fibre dosimeter is explored. • The phenomenon behind the TL variation caused by dose history is discussed. • Effect of annealing temperature on performance of fibre dosimeter is studied. • Pre-treatment methods for mitigating variation in reproducibility are proposed.

  15. Short-wavelength multiline erbium-doped fiber ring laser by a broadband long-period fiber grating inscribed in a taper transition

    International Nuclear Information System (INIS)

    Anzueto-Sánchez, G; Martínez-Rios, A

    2014-01-01

    A stable multiwavelength all-fiber erbium-doped fiber ring laser (EDFRL) based on a broadband long-period fiber grating (LPFG) inscribed in a fiber taper transition is presented. The LPFG’s characteristics were engineered to provide a higher loss at the natural lasing wavelength of the laser cavity. The LPFG inscribed on a taper transition provided a depth greater than 25 dB, and posterior chemical etching provided a broad notch band to inhibit laser generation on the long-wavelength side of the EDF gain. Up to four simultaneous laser wavelengths are generated in the range of 1530–1535 nm. (paper)

  16. Study of optical properties of Erbium doped Tellurite glass-polymer composite

    Energy Technology Data Exchange (ETDEWEB)

    Sushama, D., E-mail: sushasukumar@gmail.com [Research Awardee, LAMP, Dept. of Physics, Nit, Calicut, India and Dept. of Physics, M.S.M. College, Kayamkulam, Kerala (India)

    2014-10-15

    Chalcogenide glasses have wide applications in optical device technology. But it has some disadvantages like thermal instability. Among them Tellurite glasses exhibits high thermal Stability. Doping of rare earth elements into the Tellurite glasses improve its optical properties. To improve its mechanical properties composites of this Tellurite glasses with polymer are prepared. Bulk samples of Er{sub 2}O{sub 3} doped TeO{sub 2}‐WO{sub 3}‐La{sub 2}O{sub 3} Tellurite glasses are prepared from high purity oxide mixtures, melting in an alumina crucible in air atmosphere. Composites of this Tellurite glasses with polymer are prepared by powder mixing method and the thin films of these composites are prepared using polymer press. Variations in band gap of these composites are studied from the UV/Vis/NIR absorption.

  17. Study of optical properties of Erbium doped Tellurite glass-polymer composite

    International Nuclear Information System (INIS)

    Sushama, D.

    2014-01-01

    Chalcogenide glasses have wide applications in optical device technology. But it has some disadvantages like thermal instability. Among them Tellurite glasses exhibits high thermal Stability. Doping of rare earth elements into the Tellurite glasses improve its optical properties. To improve its mechanical properties composites of this Tellurite glasses with polymer are prepared. Bulk samples of Er 2 O 3 doped TeO 2 ‐WO 3 ‐La 2 O 3 Tellurite glasses are prepared from high purity oxide mixtures, melting in an alumina crucible in air atmosphere. Composites of this Tellurite glasses with polymer are prepared by powder mixing method and the thin films of these composites are prepared using polymer press. Variations in band gap of these composites are studied from the UV/Vis/NIR absorption

  18. Study of optical properties of Erbium doped Tellurite glass-polymer composite

    Science.gov (United States)

    Sushama, D.

    2014-10-01

    Chalcogenide glasses have wide applications in optical device technology. But it has some disadvantages like thermal instability. Among them Tellurite glasses exhibits high thermal Stability. Doping of rare earth elements into the Tellurite glasses improve its optical properties. To improve its mechanical properties composites of this Tellurite glasses with polymer are prepared. Bulk samples of Er2O3 doped TeO2-WO3-La2O3 Tellurite glasses are prepared from high purity oxide mixtures, melting in an alumina crucible in air atmosphere. Composites of this Tellurite glasses with polymer are prepared by powder mixing method and the thin films of these composites are prepared using polymer press. Variations in band gap of these composites are studied from the UV/Vis/NIR absorption.

  19. Free-standing nano-scale graphite saturable absorber for passively mode-locked erbium doped fiber ring laser

    International Nuclear Information System (INIS)

    Lin, Y-H; Lin, G-R

    2012-01-01

    The free-standing graphite nano-particle located between two FC/APC fiber connectors is employed as the saturable absorber to passively mode-lock the ring-type Erbium-doped fiber laser (EDFL). The host-solvent-free graphite nano-particles with sizes of 300 – 500 nm induce a comparable modulation depth of 54%. The interlayer-spacing and lattice fluctuations of polished graphite nano-particles are observed from the weak 2D band of Raman spectrum and the azimuth angle shift of –0.32 ° of {002}-orientation dependent X-ray diffraction peak. The graphite nano-particles mode-locked EDFL generates a 1.67-ps pulsewidth at linearly dispersion-compensated regime with a repetition rate of 9.1 MHz. The time-bandwidth product of 0.325 obtained under a total intra-cavity group-delay-dispersion of –0.017 ps 2 is nearly transform-limited. The extremely high stability of the nano-scale graphite saturable absorber during mode-locking is observed at an intra-cavity optical energy density of 7.54 mJ/cm 2 . This can be attributed to its relatively high damage threshold (one order of magnitude higher than the graphene) on handling the optical energy density inside the EDFL cavity. The graphite nano-particle with reduced size and sufficient coverage ratio can compete with other fast saturable absorbers such as carbon nanotube or graphene to passively mode-lock fiber lasers with decreased insertion loss and lasing threshold

  20. Efficacy and safety of Erbium-doped Yttrium Aluminium Garnet fractional resurfacing laser for treatment of facial acne scars

    Directory of Open Access Journals (Sweden)

    Balakrishnan Nirmal

    2013-01-01

    Full Text Available Background: Treatment of acne scars with ablative fractional laser resurfacing has given good improvement. But, data on Indian skin are limited. A study comparing qualitative, quantitative, and subjective assessments is also lacking. Aim: Our aim was to assess the improvement of facial acne scars with Erbium-doped Yttrium Aluminium Garnet (Er:YAG 2940 nm fractional laser resurfacing and its adverse effects in 25 patients at a tertiary care teaching hospital. Methods: All 25 patients received four treatment sessions with Er:YAG fractional laser at 1-month interval. The laser parameters were kept constant for each of the four sittings in all patients. Qualitative and quantitative assessments were done using Goodman and Barron grading. Subjective assessment in percentage of improvement was also documented 1 month after each session. Photographs were taken before each treatment session and 1 month after the final session. Two unbiased dermatologists performed independent clinical assessments by comparing the photographs. The kappa statistics was used to monitor the agreement between the dermatologists and patients. Results: Most patients (96% showed atleast fair improvement. Rolling and superficial box scars showed higher significant improvement when compared with ice pick and deep box scars. Patient′s satisfaction of improvement was higher when compared to physician′s observations. No serious adverse effects were noted with exacerbation of acne lesions forming the majority. Conclusion: Ablative fractional photothermolysis is both effective and safe treatment for atrophic acne scars in Indian skin.Precise evaluation of acne scar treatment can be done by taking consistent digital photographs.

  1. Shear bond strength of orthodontic brackets after acid-etched and erbium-doped yttrium aluminum garnet laser-etched

    Directory of Open Access Journals (Sweden)

    Shiva Alavi

    2014-01-01

    Full Text Available Background: Laser ablation has been suggested as an alternative method to acid etching; however, previous studies have obtained contrasting results. The purpose of this study was to compare the shear bond strength (SBS and fracture mode of orthodontic brackets that are bonded to enamel etched with acid and erbium-doped yttrium aluminum garnet (Er:YAG laser. Materials and Methods: In this experimental in vitro study, buccal surfaces of 15 non-carious human premolars were divided into mesial and distal regions. Randomly, one of the regions was etched with 37% phosphoric acid for 15 s and another region irradiated with Er:YAG laser at 100 mJ energy and 20 Hz frequency for 20 s. Stainless steel brackets were then bonded using Transbond XT, following which all the samples were stored in distilled water for 24 h and then subjected to 500 thermal cycles. SBS was tested by a chisel edge, mounted on the crosshead of universal testing machine. After debonding, the teeth were examined under Χ10 magnification and adhesive remnant index (ARI score determined. SBS and ARI scores of the two groups were then compared using t-test and Mann-Whitney U test. Significant level was set at P < 0.05. Results: The mean SBS of the laser group (16.61 ± 7.7 MPa was not significantly different from that of the acid-etched group (18.86 ± 6.09 MPa (P = 0.41. There was no significant difference in the ARI scores between two groups (P = 0.08. However, in the laser group, more adhesive remained on the brackets, which is not suitable for orthodontic purposes. Conclusion: Laser etching at 100 mJ energy produced bond strength similar to acid etching. Therefore, Er:YAG laser may be an alternative method for conventional acid-etching.

  2. Structural analysis of erbium {delta}-doped InP by OMVPE with RBS-channeling

    Energy Technology Data Exchange (ETDEWEB)

    Yuhara, Junji; Takeda, Hitoshi; Matsubara, Naoki; Tabuchi, Masao; Fujiwara, Yasufumi; Morita, Kenji; Takeda, Yoshikazu [Nagoya Univ. (Japan). School of Engineering

    1997-03-01

    We have determined the lattice location of Er in InP {delta}-doped by OMVPE with RBS-channeling. Er concentrations along the <001> and <011> directions are same as random yields, while a significant flux peaking effect is seen for the <111> direction. These data suggest that Er atoms occupy the site equivalent to the hexahedral site in InP lattice. (author)

  3. Electroplating of erbium on steel surface in ErCl3 doped LiCl-KCl

    International Nuclear Information System (INIS)

    Kondo, Masatoshi; Tanaka, Teruya; Muroga, Takeo; Tsujimura, Hiroyuki; Ito, Yasuhiko

    2012-01-01

    The electroplating of Er metal on the reduced activation ferritic martensitic steel, JLF-1 (Fe-9Cr-2W-0.1C), in a molten salt was studied. The specimen was immersed in the molten ErCl 3 doped LiCl-KCl electrolyte. The electroplating was carried out by a constant potential electrolysis method and a pulsed current electrolysis method. It was found that the Er metal was deposited on the specimen surface due to the electrochemical reaction. (author)

  4. Studies on Ytterbium-doped Fibre Laser Operating in Different Regimes

    International Nuclear Information System (INIS)

    Gan, Y; Xiang, W H; Zhang, G Z

    2006-01-01

    An ytterbium-doped fibre laser with a unidirectional ring cavity containing a polarizer placed between two in-line polarization controllers is presented. Depending on an equivalent saturable absorber, this laser operates in continuous, Q-switched mode-locked or CW mode-locked regimes. The passive method described here allowed us to choose the operating regime of the fibre laser by rotating the two polarization controllers and adjusting the pump power. Results of numerical simulations of pulse propagation in such a mode-locked fibre ring laser are presented, which reveals that the Q-switched mode-locked or CW modelocked regimes can be achieved by aligning the polarizer near the slow or the fast axes of the fibre

  5. Effect of beam expansion loss in a carbon nanotube-doped PVA film on passively mode-locked erbium-doped fiber lasers with different feedback ratios

    International Nuclear Information System (INIS)

    Cheng, Kuang-Nan; Chi, Yu-Chieh; Cheng, Chih-Hsien; Lin, Yung-Hsiang; Lo, Jui-Yung; Lin, Gong-Ru

    2014-01-01

    The effect of beam expansion induced divergent loss in a single-wall carbon nanotube (SWCNT) doped polyvinyl alcohol (PVA) based ultrafast saturable absorber (SA) film thickness on the passive mode-locking (PML) performances of erbium-doped fiber lasers are demonstrated. The variation on the PML pulsewidth of the EDFL is discussed by changing the SWCNT-PVA SA film thicknesses, together with adjusting the pumping power and the intra-cavity feedback ratio. An almost 6 dB increment of divergent loss when enlarging the SWCNT-PVA based SA film thickness from 30–130 µm is observed. When shrinking the SA thickness to 30 µm at the largest pumping power of 52.5 mW, the optical spectrum red-shifts to 1558.8 nm with its 3 dB spectral linewidth broadening up to 2.7 nm, while the pulse has already entered the soliton regime with multi-order Kelly sidebands aside the spectral shoulder. The soliton pulsewidth is as short as 790 fs, which is much shorter than those obtained with other thicker SWCNT doped PVA polymer film based SAs; therefore, the peak power from the output of the PML-EDFL is significantly enlarged accompanied by a completely suppressed residual continuous-wave level to achieve the largest on/off extinction ratio. The main mechanism of pulse shortening with reducing thickness of SWCNT doped PVA polymer film based SA is attributed to the limited beam expansion as well as the enlarged modulation depth, which results in shortened soliton pulsewidth with a clean dc background, and broadened spectrum with enriched Kelly sidebands. The increase of total SWCNT amount in the thicker SA inevitably causes a higher linear absorption; hence, the mode-locking threshold also rises accordingly. By enlarging pumping power from 38.5–52.5 mW, the highest ascent on pulse extinction of up to 32 dB is observed among all kinds of feedback conditions. Nevertheless, the enlargement on the extinction slightly decays with increasing the feedback ratio from 30–90

  6. Properties and structure of high erbium doped phosphate glass for short optical fibers amplifiers

    International Nuclear Information System (INIS)

    Seneschal, Karine; Smektala, Frederic; Bureau, Bruno; Floch, Marie Le; Jiang Shibin; Luo, Tao; Lucas, Jacques; Peyghambarian, Nasser

    2005-01-01

    New phosphate glasses have been developed in order to incorporate high rare-earth ions concentrations. These glasses present a great chemical stability and a high optical quality. The phosphate glass network is open, very flexible, with a linkage of the tetrahedrons very disordered and contains a larger number of non-bridging oxygens (66%). The great stability and resistance against crystallization associated with the possibility to incorporate high doping concentration of rare-earth ions in these phosphate glasses make them very good candidates for the realization of ultra short single mode amplifiers with a high gain at 1.55 μm

  7. Synthesis and characterization of ceramic powders of pure and doped with trivalent erbium barium tungstate

    International Nuclear Information System (INIS)

    Sousa, R.B. de; Nascimento, V.A. do; Matos, J. M.E. de; Santos, M.R.M.C.

    2014-01-01

    This research proposes the synthesis and characterization of pure and doped with Er"3"+ (1 and 2 %) barium tungstate powders prepared by the coprecipitation method. In order to characterize the obtained powders were used X-Ray Diffractometry, Raman Spectroscopy and Fourier Transform Infrared Spectroscopy. According to the standard XRD spectra, the crystals exhibited the presence of tetragonal scheelite structure without the presence of secondary phases. Raman spectra showed the presence of eleven vibrational modes and two modes were observed in the infrared spectra. The synthesized oxides showed good crystallinity and structurally ordered at short and long-range. (author)

  8. High performance yttrium-doped BSCF hollow fibre membranes

    DEFF Research Database (Denmark)

    Haworth, P.; Smart, S.; Glasscock, Julie

    2012-01-01

    measurements in air was similar for both compositions, suggesting that the higher oxygen fluxes obtained for BSCFY hollow fibres could be attributed to the higher non-stoichiometry due to yttrium addition to the BSCF crystal structure. In addition, the improvement of oxygen fluxes for small wall thickness (∼0...

  9. Efficient diode pumped ytterbium-doped fibre laser

    Czech Academy of Sciences Publication Activity Database

    Harun, S.W.; Paul, M.C.; Moghaddam, M.R.A.; Das, S.; Sen, R.; Dhar, Anirban; Pal, M.; Bhadra, S.K.; Ahmad, H.

    2010-01-01

    Roč. 46, č. 1 (2010), s. 68-69 ISSN 0013-5194 Institutional research plan: CEZ:AV0Z20670512 Keywords : Fibre lasers * Oscillator * Diode-pumped Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.001, year: 2010

  10. Topological insulator: Bi{sub 2}Se{sub 3}/polyvinyl alcohol film-assisted multi-wavelength ultrafast erbium-doped fiber laser

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Bo; Yao, Yong, E-mail: yaoyong@hit.edu.cn; Yang, Yan-Fu; Yuan, Yi-Jun; Wang, Rui-Lai [Department of Electronic and Information Engineering, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Wang, Shu-Guang; Ren, Zhong-Hua [Department of Materials Science and Engineering, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Yan, Bo [College of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450052 (China)

    2015-02-14

    We experimentally demonstrate a multi-wavelength ultrafast erbium-doped fiber laser incorporating a μm-scale topological insulator: Bi{sub 2}Se{sub 3}/Polyvinyl Alcohol film as both an excellent saturable absorber for mode-locking and a high-nonlinear medium to induce a giant third order optical nonlinear effect for mitigating the mode competition of erbium-doped fiber laser and stabilizing the multi-wavelength oscillation. By properly adjusting the pump power and the polarization state, the single-, dual-, triple-, four-wavelength mode-locking pulse could be stably initiated. For the four-wavelength operation, we obtain its pulse width of ∼22 ps and a fundamental repetition rate of 8.83 MHz. The fiber laser exhibits the maximum output power of 9.7 mW with the pulse energy of 1.1 nJ and peak power of 50 W at the pump power of 155 mW. Our study shows that the simple, stable, low-cost multi-wavelength ultrafast fiber laser could be applied in various potential fields, such as optical communication, biomedical research, and radar system.

  11. Thermal Stability and Optical Activity of Erbium Doped Chalcogenide Glasses for Photonics

    Science.gov (United States)

    Tonchev, D.; Koughia, K.; Kasap, S. O.; Maeda, K.; Sakai, T.; Ikuta, J.; Ivanova, Z. G.

    The glass transition and crystallization temperatures (T g , T c ), heat capacity, thermal stability and glass uniformity of GeSGa, GeSeGa, Ge(SeTe)Ga chalcogenide glasses doped with Er3+ by the addition of Er2S3 have been investigated by conventional differential scanning calorimetry (DSC) and Temperature-Modulated DSC (TMDSC). While some of the glasses have two crystallization peaks, these glasses were nonetheless optically actively and uniform. Essential optical properties have been evaluated, such as the photoluminescence (PL) intensity and lifetime as a function of the glass composition. We present typical results to emphasize some of the important characteristics of these systems and discuss trends within a glass system; and also highlight differences between glass systems.

  12. Erbium-doped phosphate glass waveguide on silicon with 4.1 dB/cm gain at 1.535 µm

    Science.gov (United States)

    Yan, Y. C.; Faber, A. J.; de Waal, H.; Kik, P. G.; Polman, A.

    1997-11-01

    Erbium-doped multicomponent phosphate glass waveguides were deposited by rf sputtering techniques. The Er concentration was 5.3×1020cm-3. By pumping the waveguide at 980 nm with a power of ˜21 mW, a net optical gain of 4.1 dB at 1.535 μm was achieved. This high gain per unit length at low pump power could be achieved because the Er-Er cooperative upconversion interactions in this heavily Er-doped phosphate glass are very weak [the upconversion coefficient is (2.0±0.5)×10-18 cm3/s], presumably due to the homogeneous distribution of Er in the glass and due to the high optical mode confinement in the waveguide which leads to high pump power density at low pump power.

  13. Nonlinear resonance phenomena of a doped fibre laser under cavity ...

    Indian Academy of Sciences (India)

    quence and other routes to chaos, generalized multistability and crisis. But, doped ... of chaos and synchronization of coupled chaotic lasers (for communication with a ... The two basic issues in focus here for the nonlinear dynamical studies.

  14. Effect of B2O3 on luminescence of erbium doped tellurite glasses.

    Science.gov (United States)

    Shen, Xiang; Nie, Qiuhua; Xu, Tiefeng; Dai, Shixun; Wang, Xunsi

    2007-02-01

    The B2O3 was introduced into the Er3+ doped TeO2-ZnO-Na2O glass to increase the phonon energy of the host. The effect of B2O3 on the non-radiative rate of the 4I11/2-->4I13/2 transition of Er3+, the lifetime of the 4I11/2 and 4I13/2 levels, the green and red upconversion emissions intensity, and the 4I13/2-->4I15/2 emission intensity was discussed. The results show that the phonon energy of boro-tellurite glass is close to that of germanate glass and is quite smaller than that of borate glass. The lifetime of 4I11/2 level and the upconversion emissions decrease with increasing B2O3 concentration. The higher OH group concentration presented in the boro-tellurite glass may shorten the lifetime of 4I13/2 level and also reduce the quantum efficiency of 4I13/2-->4I15/2 emission. The future dehydrating procedures are suggested to enhance the efficiency of amplification at 1.5 microm band.

  15. Preparation and microstructural properties of erbium doped alumina–yttria oxide thin films deposited by aerosol MOCVD

    Energy Technology Data Exchange (ETDEWEB)

    Salhi, Rached, E-mail: salhi_rached@yahoo.fr [Laboratoire de Science et Ingénierie des MAtériaux et Procédés 1130 rue de la PiscineBP 75-F-38402 Saint Martin D’Hères Cedex 1 (France); Laboratoire des Matériaux et du Génie Physique, CNRS UMR 5628, INP Grenoble-Minatec, 3 parvis Louis Néel BP 257, 38 016 Grenoble Cedex 1 (France); Jimenez, Carmen; Deschanvres, Jean-Luc [Laboratoire des Matériaux et du Génie Physique, CNRS UMR 5628, INP Grenoble-Minatec, 3 parvis Louis Néel BP 257, 38 016 Grenoble Cedex 1 (France); Guyot, Yannick [LPCML-UMR 5620 CNRS/UCBL Universite´ Claude Bernard Lyon 110 Rue Ada Byron 69622 Villeurbanne Cedex (France); Chaix-Pluchery, Odette; Rapenne, Laetitia [Laboratoire des Matériaux et du Génie Physique, CNRS UMR 5628, INP Grenoble-Minatec, 3 parvis Louis Néel BP 257, 38 016 Grenoble Cedex 1 (France); Maâlej, Ramzi [LPCML-UMR 5620 CNRS/UCBL Universite´ Claude Bernard Lyon 110 Rue Ada Byron 69622 Villeurbanne Cedex (France); Fourati, Mohieddine [Laboratoire de Chimie Industrielle, Ecole Nationale d’Ingénieur de Sfax, University of Sfax BP W 3038 Sfax (Tunisia); Laboratoire de Physique Appliquée, Groupe de Physique Théorique, Département de Physique, Faculté des Sciences de Sfax, University of Sfax 3018 Sfax (Tunisia)

    2013-10-15

    Erbium-doped aluminum–yttrium oxide films (Er: Al{sub 2}O{sub 3}–Y{sub 2}O{sub 3}) were prepared by aerosol-UV assisted Metalorganic Chemical Vapor Deposition (MOCVD) at 410 °C and annealed at 1000 °C. The effects of humidity of carrier gas and UV-assistance on their structure and optical properties were investigated using scanning electron microscope, X-ray diffraction and Transmission electron microscopy. It was found that under low air humidity and without UV-assistance the films present a low mol% Al{sub 2}O{sub 3} (10 mol%) two different structural phases are observed corresponding to the cubic and the monoclinic structures of Y{sub 2}O{sub 3}. When the deposition takes place under high air humidity and with UV assistance the Er:Al{sub 2}O{sub 3}–Y{sub 2}O{sub 3} films present a very high mol% Al{sub 2}O{sub 3} (88 mol%) and crystallize in the Y{sub 3}Al{sub 5}O{sub 12} (YAG) compound mixed with an amorphous phase. The Er{sup 3+} luminescence analyzed in the visible and IR regions, shows the classical green transitions. The best optical properties were obtained with the Er:Al{sub 2}O{sub 3}–Y{sub 2}O{sub 3} films grown under high air humidity with UV-assistance. Under such deposition conditions, {sup 4}I{sub 13/2} lifetimes was found to be 1.1 ms. This indicates that the deposition conditions, in particular air humidity, play an important role in the luminescent properties even after annealing. -- Highlights: • We investigate the effects of humidity and UV on the properties of Er:Al{sub 2}O{sub 3}–Y{sub 2}O{sub 3}. • Under low air humidity and without UV-assistance the films present a low mol% Al{sub 2}O{sub 3}. • Under high air humidity and with UV the Er:Al{sub 2}O{sub 3}–Y{sub 2}O{sub 3} present high mol% Al{sub 2}O{sub 3}. • The film crystallize in the YAG phase mixed with an amorphous phase. • The best optical properties were obtained under high air humidity with UV-assistance.

  16. Preparation and infrared emission of silica-zirconia-alumina doped with erbium for planar waveguide

    International Nuclear Information System (INIS)

    Thu Huong, T.; Kim Anh, T.; Hoai Nam, M.; Barthou, C.; Strek, W.; Quoc Minh, L.

    2007-01-01

    The sol-gel synthesis of Er 3+ (1-5%) doped silica(83)-zirconia(17) waveguide materials with addition of aluminum (6-20 at%) giving a FWHM ( 4 I 13/2 - 4 I 15/2 )>60 nm is reported. Zirconia with high refractive index of 1.9 and low phonon energy is a good material compared with titania. The films were deposited on silicon or silica substrate by dipcoating technique using the precursors of Si(OC 2 H 5 ) 4 (Aldrich), Zr(C 3 H 7 O) 4 , CH 3 -CH(OH)-CH 3 , C 5 H 8 O 2 , Al(NO 3 ) 3 .9H 2 O, Er(NO 3 ) 3 .5H 2 O and Yb(NO 3 ) 3 .5H 2 O (Merck). The dipcoating rate of 2 and 3 mm/s were controlled by computer. Samples were calcinated at temperatures from 70 to 900 deg. C. The optical properties were studied by photoluminescent spectra and decay time. Influence of the Al 3+ concentration and the heat treatment conditions for the Er 3+ luminescent properties were studied. An energy transfer from 2 F 5/2 (Yb 3+ ) to 4 I 11/2 (Er 3+ ) multiplets is followed by a relaxation to the 4 I 13/2 (Er 3+ ) and an efficiency luminescence of Er 3+ ( 4 I 13/2 - 4 I 15/2 ) was clearly measured. It is interesting to indicate that the lifetime of few ms of Er 3+ at 1530 nm in the sample Si(83)Zr(17)Al(6%)Er(1%)Yb(1%) is longer than for the sample without Yb ions. Multilayer thin films were prepared. The thickness, refractive index, the roughness about 2 nm and a propagation loss<2.5 dB/cm were studied for active planar waveguide applications

  17. Assessment of effect of Yb3+ ion pairs on a highly Yb-doped double-clad fibre laser

    Science.gov (United States)

    Vallés, J. A.; Martín, J. C.; Berdejo, V.; Cases, R.; Álvarez, J. M.; Rebolledo, M. Á.

    2018-03-01

    Using a previously validated characterization method based on the careful measurement of the characteristic parameters and fluorescence emission spectra of a highly Yb-doped double-clad fibre, we evaluate the contribution of ion pair induced processes to the output power of a double-clad Yb-doped fibre ring laser. This contribution is proved to be insignificant, contrary to analysis by other authors, who overestimate the role of ion pairs.

  18. Effect of heat treatment on the structural and optical properties of tellurite glasses doped erbium

    Energy Technology Data Exchange (ETDEWEB)

    Jlassi, I., E-mail: ifa.jlassi@fst.rnu.tn [Laboratoire de Physico-Chimie des Materiaux Mineraux et leurs Applications, Centre National de Recherches en Sciences des Materiaux, B.P. 95 Hammam-Lif 2050 (Tunisia); Elhouichet, H. [Laboratoire de Physico-Chimie des Materiaux Mineraux et leurs Applications, Centre National de Recherches en Sciences des Materiaux, B.P. 95 Hammam-Lif 2050 (Tunisia); Departement de Physique, Faculte des Sciences de Tunis, Campus ElManar 2092 (Tunisia); Hraiech, S.; Ferid, M. [Laboratoire de Physico-Chimie des Materiaux Mineraux et leurs Applications, Centre National de Recherches en Sciences des Materiaux, B.P. 95 Hammam-Lif 2050 (Tunisia)

    2012-03-15

    The 75TeO{sub 2}-20ZnO-4Na{sub 2}CO{sub 3}-1Er{sub 2}O{sub 3} (in molar ratio) glass system was prepared by the conventional melt-quenching method. As such, the samples prepared were investigated by differential scanning calorimetry (DSC), X-ray diffractrometry (XRD), Raman spectroscopy and infrared luminescence. DSC analyses were carried out on our glass at different heating rates between 5 and 20 Degree-Sign C/min. The result of the annealing temperature on the spectroscopic properties of Er{sup 3+} in tellurite glasses was discussed. The activation energy, for surface crystallization, was determined graphically from a Kissinger-type plot and had a value about 897.2 kJ/mol. Crystalline phases for both {alpha}-TeO{sub 2}, {gamma}-TeO{sub 2} and Zn{sub 2}Te{sub 3}O{sub 8} system were determined by the XRD method and were confirmed by Raman spectroscopy characterizations after heat treatment. The effect of heat treatment on absorption spectra and luminescence properties in the tellurite glass was also investigated. With heat treatment, the ultraviolet absorption edge presented a redshift. As a result, the Judd-Ofelt (J-O) intensity parameters ({Omega}{sub 2}, {Omega}{sub 4}, {Omega}{sub 6}) were determined. The spontaneous emission probabilities of some relevant transitions, the branching ratio and the radiative lifetimes of several excited states of Er{sup 3+} were predicted using intensity J-O parameters. The near infrared emission that corresponds to Er{sup 3+}: {sup 4}I{sub 13/2}{yields}{sup 4}I{sub 15/2} can be significantly enhanced after heat treatment. Notably, it is found that the luminescence lifetime in the present system is much longer than that in most other glasses and glass ceramics. A comparative study on luminescence performance suggests that the obtained glass ceramic is a promising material for Er{sup 3+} doped fiber amplifiers. - Highlights: Black-Right-Pointing-Pointer Tellurite glasses were prepared by conventional melt-quenching method. Black

  19. Modification of erbium photoluminescence decay rate due to ITO layers on thin films of SiO{sub 2}:Er doped with Si-nanoclusters

    Energy Technology Data Exchange (ETDEWEB)

    Wojdak, M., E-mail: m.wojdak@ucl.ac.uk [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Jayatilleka, H. [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Department of Electrical and Computer Engineering, University of Toronto, 10 King' s College Road, Toronto, Ontario, Canada M5S 3G4 (Canada); Shah, M. [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Kenyon, A.J., E-mail: t.kenyon@ucl.ac.uk [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Gourbilleau, F.; Rizk, R. [Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), ENSICAEN, CNRS, CEA/IRAMIS, Université de Caen, 14050 CAEN cedex (France)

    2013-04-15

    During the fabrication of MOS light emitting devices, the thin film of active material is usually characterized by photoluminescence measurements before electrical contacts are deposited. However, the presence of a conductive contact layer can alter the luminescent properties of the active material. The local optical density of states changes due to the proximity of luminescent species to the interface with the conductive medium (the top electrode), and this modifies the radiative rate of luminescent centers within the active layer. In this paper we report enhancement of the observed erbium photoluminescence rate after deposition of indium tin oxide contacts on thin films of SiO{sub 2}:Er containing silicon nanoclusters, and relate this to Purcell enhancement of the erbium radiative rate. -- Highlights: ► We studied photoluminescence of Er in SiO{sub 2} thin films doped with Si nanoclusters. ► Presence of ITO layer on the top enhances photoluminescence decay rate of Er. ► The effect depends on the thickness of active film. ► Radiative rate change in proximity of ITO layer was calculated theoretically. ► The calculation results are compared with the experiment and discussed.

  20. Repetition rate stabilization of an erbium-doped all-fiber laser via opto-mechanical control of the intracavity group velocity

    International Nuclear Information System (INIS)

    Shen, Xuling; He, Boqu; Zhao, Jian; Liu, Yang; Bai, Dongbi; Wang, Chao; Liu, Geping; Luo, Daping; Liu, Fengjiang; Li, Wenxue; Zeng, Heping; Yang, Kangwen; Hao, Qiang

    2015-01-01

    We present a method for stabilizing the repetition rate of an erbium-doped all-fiber laser by inserting an electronic polarization controller (EPC) in the fiber laser cavity. The device exhibited good integration, low cost, and convenient operation. Such a repetition rate stabilization may facilitate an all-fiber laser comb system with high integration. The repetition rate was phase-locked to a Rb reference more than 72 h with a low feedback voltage applied to one channel of the EPC. The repetition rate was 74.6 MHz. The standard deviation and the repetition rate linewidth were 1.4 and 1.7 mHz, respectively

  1. Tunable Q-switched erbium doped fiber laser based on metal transition oxide saturable absorber and refractive index characteristic of multimode interference effects

    Science.gov (United States)

    Mohammed, D. Z.; Khaleel, Wurood Abdulkhaleq; Al-Janabi, A. H.

    2017-12-01

    Ferro-oxide (Fe3O4) nanoparticles were used as a saturable absorber (SA) for a passively Q-switched erbium doped fiber laser (EDFL) with ring cavity. The Q-switching operation was achieved at a pump threshold of 80 mW. The proposed fiber laser produces stable pulses train of repetition rate ranging from 25 kHz to 80 kHz as the pump power increases from threshold to 342 mW. The minimum recorded pulse width was 2.7 μs at 342 mW. The C-band tunability operation was performed using single mode-multimode-single mode fiber (SM-MM-SM) structure. The laser exhibited a total tuning range of 7 nm, maximum sensitivity of 106.9 nm, optical signal to noise ratio (OSNR) of 38 dB and 3-dB linewidth of 0.06 nm.

  2. Multiwavelength mode-locked erbium-doped fiber laser based on the interaction of graphene and fiber-taper evanescent field

    International Nuclear Information System (INIS)

    Luo, Z Q; Wang, J Z; Zhou, M; Xu, H Y; Cai, Z P; Ye, C C

    2012-01-01

    We report on the generation of multiwavelength passively mode-locked pulses in an erbium-doped fiber laser (EDFL) based on the interaction of graphene and fiber-taper evanescent field. Graphene-polymer nanocomposites in aqueous suspension are trapped by the optical evanescent light and deposited on taper region. The graphene-deposited fiber-taper device not only acts as an excellent saturable absorber for mode-locking, but also induces a polarizing effect to form an artificial birefringent filter for multiwavelength selection. By simultaneously exploiting both functions of this device, four-wavelength continuous-wave mode-locking operation of an EDFL is stably initiated with a pulse width of 8.8 ps and a fundamental repetition rate of 8.034 MHz. This is the first time, to our knowledge, the mode-locked EDFL using such a new geometry of graphene-based tapered-fiber saturable absorber has been demonstrated

  3. Repetition frequency scaling of an all-polarization maintaining erbium-doped mode-locked fiber laser based on carbon nanotubes saturable absorber

    Energy Technology Data Exchange (ETDEWEB)

    Sotor, J., E-mail: jaroslaw.sotor@pwr.edu.pl; Sobon, G.; Abramski, K. M. [Laser and Fiber Electronics Group, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Jagiello, J.; Lipinska, L. [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland)

    2015-04-07

    We demonstrate an all-polarization maintaining (PM), mode-locked erbium (Er)-doped fiber laser based on a carbon nanotubes (CNT) saturable absorber (SA). The laser resonator was maximally simplified by using only one passive hybrid component and a pair of fiber connectors with deposited CNTs. The repetition frequency (F{sub rep}) of such a cost-effective and self-starting mode-locked laser was scaled from 54.3 MHz to 358.6 MHz. The highest F{sub rep} was obtained when the total cavity length was shortened to 57 cm. The laser allows ultrashort pulse generation with the duration ranging from 240 fs to 550 fs. Because the laser components were based on PM fibers the laser was immune to the external perturbations and generated laniary polarized light with the degree of polarization (DOP) of 98.7%.

  4. Thermal characteristics of an end-pumped high-power ytterbium-sensitized erbium-doped fiber laser under natural convection.

    Science.gov (United States)

    Jeong, Y; Baek, S; Dupriez, P; Maran, J-N; Sahu, J K; Nilsson, J; Lee, B

    2008-11-24

    We investigate the thermal characteristics of a polymer-clad fiber laser under natural convection when it is strongly pumped up to the damage point of the fiber. For this, we utilize a temperature sensing technique based on a fiber Bragg grating sensor array. We have measured the longitudinal temperature distribution of a 2.4-m length ytterbium-sensitized erbium-doped fiber laser that was end-pumped at approximately 975 nm. The measured temperature distribution decreases exponentially, approximately, decaying away from the pump-launch end. We attribute this to the heat dissipation of absorbed pump power. The maximum temperature difference between the fiber ends was approximately 190 K at the maximum pump power of 60.8 W. From this, we estimate that the core temperature reached approximately 236 degrees C.

  5. Transfer of an exfoliated monolayer graphene flake onto an optical fiber end face for erbium-doped fiber laser mode-locking

    International Nuclear Information System (INIS)

    Rosa, Henrique Guimaraes; De Souza, Eunézio A Thoroh; Gomes, José Carlos Viana

    2015-01-01

    This paper presents, for the first time, the successful transfer of exfoliated monolayer graphene flake to the optical fiber end face and alignment to its core. By fabricating and optimizing a polymeric poly(methyl methacrylate) (PMMA) and polyvinyl alcohol (PVA) substrate, it is possible to obtain a contrast of up to 11% for green light illumination, allowing the identification of monolayer graphene flakes that were transferred to optical fiber samples and aligned to its core. With Raman spectroscopy, it is demonstrated that graphene flake completely covers the optical fiber core, and its quality remains unaltered after the transfer. The generation of mode-locked erbium-doped fiber laser pulses, with a duration of 672 fs, with a single-monolayer graphene flake as a saturable absorber, is demonstrated for the first time. This transfer technique is of general applicability and can be used for other two-dimensional (2D) exfoliated materials. (letter)

  6. Stable and High OSNR Compound Linear-Cavity Single-Longitudinal-Mode Erbium-Doped Silica Fiber Laser Based on an Asymmetric Four-Cavity Structure

    International Nuclear Information System (INIS)

    Feng Ting; Yan Feng-Ping; Li Qi; Peng Wan-Jing; Feng Su-Chun; Wen Xiao-Dong; Tan Si-Yu; Liu Peng

    2012-01-01

    We propose a stable and high optical signal-to-noise ratio (OSNR) compound linear-cavity single-longitudinal-mode (SLM) erbium-doped silica fiber laser. It consists of three uniform fiber Bragg gratings (FBGs) and two fiber couplers to form a simple asymmetric four-cavity structure to select the longitudinal mode. The stable SLM operation at the wavelength of 1544.053 nm with a 3 dB bandwidth of 0.014 nm and an OSNR of ∼60 dB was verified experimentally. Under laboratory conditions, a power fluctuation performance of less than 0.05 dB for 5 h and wavelength variation of less than 0.01 nm for about 150 min is demonstrated. Finally, the characteristic of laser output power as a function of pump power is investigated. The proposed system provides a simple and cost-effective approach to realize a stable SLM fiber laser

  7. Doping porous silicon with erbium: pores filling as a method to limit the Er-clustering effects and increasing its light emission

    KAUST Repository

    Mula, Guido; Printemps, Tony; Licitra, Christophe; Sogne, Elisa; D’ Acapito, Francesco; Gambacorti, Narciso; Sestu, Nicola; Saba, Michele; Pinna, Elisa; Chiriu, Daniele; Ricci, Pier Carlo; Casu, Alberto; Quochi, Francesco; Mura, Andrea; Bongiovanni, Giovanni; Falqui, Andrea

    2017-01-01

    Er clustering plays a major role in hindering sufficient optical gain in Er-doped Si materials. For porous Si, the long-standing failure to govern the clustering has been attributed to insufficient knowledge of the several, concomitant and complex processes occurring during the electrochemical Er-doping. We propose here an alternative road to solve the issue: instead of looking for an equilibrium between Er content and light emission using 1-2% Er, we propose to significantly increase the electrochemical doping level to reach the filling the porous silicon pores with luminescent Er-rich material. To better understand the intricate and superposing phenomena of this process, we exploit an original approach based on needle electron tomography, EXAFS and photoluminescence. Needle electron tomography surprisingly shows a heterogeneous distribution of Er content in the silicon thin pores that until now couldn't be revealed by the sole use of scanning electron microscopy compositional mapping. Besides, while showing that pore filling leads to enhanced photoluminescence emission, we demonstrate that the latter is originated from both erbium oxide and silicate. These results give a much deeper understanding of the photoluminescence origin down to nanoscale and could lead to novel approaches focused on noteworthy enhancement of Er-related photoluminescence in porous silicon.

  8. Doping porous silicon with erbium: pores filling as a method to limit the Er-clustering effects and increasing its light emission

    KAUST Repository

    Mula, Guido

    2017-07-14

    Er clustering plays a major role in hindering sufficient optical gain in Er-doped Si materials. For porous Si, the long-standing failure to govern the clustering has been attributed to insufficient knowledge of the several, concomitant and complex processes occurring during the electrochemical Er-doping. We propose here an alternative road to solve the issue: instead of looking for an equilibrium between Er content and light emission using 1-2% Er, we propose to significantly increase the electrochemical doping level to reach the filling the porous silicon pores with luminescent Er-rich material. To better understand the intricate and superposing phenomena of this process, we exploit an original approach based on needle electron tomography, EXAFS and photoluminescence. Needle electron tomography surprisingly shows a heterogeneous distribution of Er content in the silicon thin pores that until now couldn\\'t be revealed by the sole use of scanning electron microscopy compositional mapping. Besides, while showing that pore filling leads to enhanced photoluminescence emission, we demonstrate that the latter is originated from both erbium oxide and silicate. These results give a much deeper understanding of the photoluminescence origin down to nanoscale and could lead to novel approaches focused on noteworthy enhancement of Er-related photoluminescence in porous silicon.

  9. Numerical analysis of multifrequency erbium-doped fiber ring laser employing a periodic filter and frequency shifter

    Czech Academy of Sciences Publication Activity Database

    Karásek, Miroslav; Bellemare, A.

    2000-01-01

    Roč. 147, č. 2 (2000), s. 115-119 ISSN 1350-2433 Institutional research plan: CEZ:AV0Z2067918 Keywords : optical fibre amplifiers * fibre lasers Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.792, year: 2000

  10. Dopant concentration and thermoluminescence (TL) properties of tailor-made Ge-doped SiO2 fibres

    International Nuclear Information System (INIS)

    Zahaimi, Nurul Arina; Ooi Abdullah, Mohd Haris Ridzuan; Zin, Hafiz; Abdul Rahman, Ahmad Lutfi; Hashim, Suhairul; Saripan, Mohd Iqbal; Paul, Mukul Chandra; Bradley, D.A.; Abdul Rahman, Ahmad Taufek

    2014-01-01

    Study focuses on characterisation of diverse concentrations of Ge-doped SiO 2 fibre as a potential thermoluminescence (TL) system for radiotherapy dosimetry. Irradiations were made using a linear accelerator providing 6 MV and 10 MV photon beams. Investigation has been done on various doped core diameter Ge-doped SiO 2 glass fibres such as commercial telecommunication fibres of 8 µm and 9 µm (CorActive High Tech, Canada), tailor-made fibres of 23 and 50 µm produced by the Central Glass and Ceramic Research Institute Kolkata, and tailor-made fibres of 11 µm produced by the University of Malaya Photonics Research Centre. The fibres have been characterised for TL sensitivity, reproducibility, dose- and energy-dependence. The area under the TL glow curve increases with increasing core diameter. For repeat irradiations at a fixed dose the dosimeter produces a flat response better than 4% (1SD) of the mean of the TL distribution. Minimal TL signal fading was found, less than 0.5% per day post irradiation. Linearity of TL has been observed with a correlation coefficient (r 2 ) of better than 0.980 (at 95% confidence level). For particular dopant concentrations, the least square fits show the change in TL yield, in counts per second per unit mass, obtained from 50 µm core diameter fibres irradiated at 6 MV of photon to be 8 times greater than that of 8 µm core diameter fibre. With respect to energy response, the TL yield at 10 MV decreases by∼5% compared to that at 6 MV, primarily due to the lower mass energy absorption coefficient at higher photon energy. These early results indicate that selectively screened fibres can be developed into a promising TL system, offering high spatial resolution capability and, with this, verification of complex radiotherapy dose distributions. - Highlights: • We examined the TL glow curve intensity for various diameter sizes of germanium doped silica glass fibre. • TL sensitivity increased with the increase of fibre core

  11. Bismuth-doped fibre amplifier operating between 1600 and 1800 nm

    Energy Technology Data Exchange (ETDEWEB)

    Firstov, S V; Alyshev, S V; Riumkin, K E; Mel' kumov, M A; Dianov, E M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Khopin, V F; Gurjanov, A N [G.G.Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

    2015-12-31

    We report the first bismuth-doped fibre amplifier operating between 1600 and 1800 nm, which utilises bidirectional pumping (co-propagating and counter-propagating pump beams) by laser diodes at a wavelength of 1550 nm. The largest gain coefficient of the amplifier is 23 dB, at a wavelength of 1710 nm. It has a noise figure of 7 dB, 3-dB gain bandwidth of 40 nm and gain efficiency of 0.1 dB mW{sup -1}. (letters)

  12. High performance architecture design for large scale fibre-optic sensor arrays using distributed EDFAs and hybrid TDM/DWDM

    Science.gov (United States)

    Liao, Yi; Austin, Ed; Nash, Philip J.; Kingsley, Stuart A.; Richardson, David J.

    2013-09-01

    A distributed amplified dense wavelength division multiplexing (DWDM) array architecture is presented for interferometric fibre-optic sensor array systems. This architecture employs a distributed erbium-doped fibre amplifier (EDFA) scheme to decrease the array insertion loss, and employs time division multiplexing (TDM) at each wavelength to increase the number of sensors that can be supported. The first experimental demonstration of this system is reported including results which show the potential for multiplexing and interrogating up to 4096 sensors using a single telemetry fibre pair with good system performance. The number can be increased to 8192 by using dual pump sources.

  13. Establishment of Ge-doped optical fibres as thermoluminescence dosimeters for brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Issa, Fatma, E-mail: f.issa@surrey.ac.uk [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Department of Radiotherapy, Tripoli Medical Centre (TMC), Tripoli (Libya); Abdul Rahman, A.T. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); School of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA Malaysia, Campus of Negeri Sembilan, 72000 Kuala Pilah (Malaysia); Hugtenburg, Richard P. [Department of Medical Physics and Clinical Engineering, Abertawe Bro Morgannwg UHB and School of Medicine, Swansea University, Swansea, SA2 8PP (United Kingdom); Bradley, David A. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Department of Radiological Sciences, King Saud University, P.O. Box 10219, Riyadh 11432 (Saudi Arabia); Nisbet, Andrew [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Department of Medical Physics, Royal Surrey County Hospital NHS Foundation Trust, Guildford, GU2 7XX (United Kingdom)

    2012-07-15

    This study aims to establish the sensitive, {approx}120 {mu}m high spatial resolution, high dynamic range Ge-doped optical fibres as thermoluminescence (TL) dosimeters for brachytherapy dose distribution. This requires investigation to accommodate sensitivity of detection, both for the possibility of short range dose deposition from beta components as well as gamma/x-mediated dose. In-air measurements are made at distances close to radionuclide sources, evaluating the fall off in dose along the transverse axis of {sup 133}Ba and {sup 60}Co radioactive sources, at distances from 2 mm up to 20 mm from their midpoints. Measurements have been compared with Monte Carlo code DOSRZnrc simulations for photon-mediated dose only, agreement being obtained to within 3% and 1% for the {sup 133}Ba and {sup 60}Co sources, respectively. As such, in both cases it is determined that as intended, beta dose has been filtered out by source encapsulation. - Highlights: Black-Right-Pointing-Pointer We seek to establish Ge-doped optical fibres as TLDs for brachytherapy. Black-Right-Pointing-Pointer Dose was evaluated along the central axis of {sup 133}Ba and {sup 60}Co, at 2 mm-20 mm. Black-Right-Pointing-Pointer We verify values using DOSRZnrc Monte Carlo code simulations. Black-Right-Pointing-Pointer Good agreement is between dose measurements and calculation to within 3% and 1%. Black-Right-Pointing-Pointer Methodology is to be used in obtaining doses around {sup 125}I and {sup 192}Ir sources.

  14. Establishment of Ge-doped optical fibres as thermoluminescence dosimeters for brachytherapy

    International Nuclear Information System (INIS)

    Issa, Fatma; Abdul Rahman, A.T.; Hugtenburg, Richard P.; Bradley, David A.; Nisbet, Andrew

    2012-01-01

    This study aims to establish the sensitive, ∼120 μm high spatial resolution, high dynamic range Ge-doped optical fibres as thermoluminescence (TL) dosimeters for brachytherapy dose distribution. This requires investigation to accommodate sensitivity of detection, both for the possibility of short range dose deposition from beta components as well as gamma/x-mediated dose. In-air measurements are made at distances close to radionuclide sources, evaluating the fall off in dose along the transverse axis of 133 Ba and 60 Co radioactive sources, at distances from 2 mm up to 20 mm from their midpoints. Measurements have been compared with Monte Carlo code DOSRZnrc simulations for photon-mediated dose only, agreement being obtained to within 3% and 1% for the 133 Ba and 60 Co sources, respectively. As such, in both cases it is determined that as intended, beta dose has been filtered out by source encapsulation. - Highlights: ► We seek to establish Ge-doped optical fibres as TLDs for brachytherapy. ► Dose was evaluated along the central axis of 133 Ba and 60 Co, at 2 mm–20 mm. ► We verify values using DOSRZnrc Monte Carlo code simulations. ► Good agreement is between dose measurements and calculation to within 3% and 1%. ► Methodology is to be used in obtaining doses around 125 I and 192 Ir sources.

  15. Novel high resolution 125I brachytherapy source dosimetry using Ge-doped optical fibres

    International Nuclear Information System (INIS)

    Issa, Fatma; Hugtenburg, Richard P.; Nisbet, Andrew; Bradley, David A.

    2013-01-01

    The steep dose gradients close to brachytherapy sources limit the ability to obtain accurate measurements of dose. Here we use a novel high spatial resolution dosimeter to measure dose around a 125 I source and compare against simulations. Ge-doped optical fibres, used as thermoluminescent dosimeters, offer sub-mm spatial resolution, linear response from 10 cGy to >1 kGy and dose-rate independence. For a 125 I brachytherapy seed in a PMMA phantom, doses were obtained for source-dosimeter separations from 0.1 cm up to several cm, supported by EGSnrc/DOSRZznrc Monte Carlo simulations and treatment planning system data. The measurements agree with simulations to within 2.3%±0.3% along the transverse and perpendicular axes and within 3.0%±0.5% for measurements investigating anisotropy in angular dose distribution. Measured and Veriseed™ brachytherapy treatment planning system (TPS) values agreed to within 2.7%±0.5%. Ge-doped optical fibre dosimeters allow detailed dose mapping around brachytherapy sources, not least in situations of high dose gradient. - Highlights: • We evaluate fall-off in dose for distances from an 125 I source of 1 mm to 60 mm. • The TL of optical fibres accommodate high dose gradients and doses that reduce by a factor of 10 3 across the range of separations. • We verify measured values using DOSRZnrc Monte Carlo code simulations and the Variseed™ Treatment Planning System. • Measured radial and angular dose are obtained with ≤3% uncertainty

  16. Analysis of dynamic pump-loss controlled gain-locking system for erbium-doped fiber amplifiers

    Czech Academy of Sciences Publication Activity Database

    Karásek, Miroslav; Plaats van der, J.C.

    1998-01-01

    Roč. 10, č. 8 (1998), s. 1171-1173 ISSN 1041-1135 Grant - others:EU COST(XE) OC 241.10 Keywords : optical communication * amplifiers * fibre lasers Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.791, year: 1998

  17. Active control of long-period fiber-grating-based filters made in erbium-doped optical fibers

    Czech Academy of Sciences Publication Activity Database

    Slavík, Radan; Kulishov, M.

    2007-01-01

    Roč. 32, č. 7 (2007), s. 757-759 ISSN 0146-9592 R&D Projects: GA AV ČR(CZ) KJB200670601; GA ČR(CZ) GA102/07/0999 Institutional research plan: CEZ:AV0Z20670512 Keywords : optical fibre filters Subject RIV: BH - Optics , Masers, Lasers Impact factor: 3.711, year: 2007

  18. Simultaneous thermal stability and phase change speed improvement of Sn15Sb85 thin film through erbium doping

    Science.gov (United States)

    Zou, Hua; Zhu, Xiaoqin; Hu, Yifeng; Sui, Yongxing; Sun, Yuemei; Zhang, Jianhao; Zheng, Long; Song, Zhitang

    2016-12-01

    In general, there is a trade off between the phase change speed and thermal stability in chalcogenide phase change materials, which leads to sacrifice the one in order to ensure the other. For improving the performance, doping is a widely applied technological process. Here, we fabricated Er doped Sn15Sb85 thin films by magnetron sputtering. Compared with the pure Sn15Sb85, we show that Er doped Sn15Sb85 thin films exhibit simultaneous improvement over the thermal stability and the phase change speed. Thus, our results suggest that Er doping provides the opportunity to solve the contradiction. The main reason for improvement of both thermal stability and crystallization speed is due to the existence of Er-Sb and Er-Sn bonds in Er doped Sn15Sb85 films. Hence, Er doped Sn15Sb85 thin films are promising candidates for the phase change memory application, and this method could be extended to other lanthanide-doped phase change materials.

  19. Multifunctional stannum oxide compact bilayer modified by europium and erbium respectively doped ytterbium fluoride for high-performance dye-sensitized solar cell

    International Nuclear Information System (INIS)

    Yue, Jingyi; Xiao, Yaoming; Li, Yanping; Han, Gaoyi

    2017-01-01

    Graphical abstract: Multifunctional SnO 2 compact bilayer respectively modified by YbF 3 :Eu 3+ (SYEu) and YbF 3 :Er 3+ (SYEr) demonstrates three functions: 1) reducing the recombination rate of electron-hole pairs, 2) improving the utilization of sunlight, and 3) enhancing the long-term stability of the photovoltaic device. Display Omitted -- Highlights: •Multifunctional SYEu/SYEr compact bilayer is designed and fabricated. •The compact bilayer exhibits a reduced electron recombination rate. •The compact bilayer shows enhanced UV and IR light response via light-conversions. •The double layer has no significant influence on arising quenching effect. -- Abstract: Multifunctional stannum oxide compact bilayer modified by europium and erbium respectively doped ytterbium fluoride (SYEu/SYEr) is designed and prepared by a convenient and low-cost spin-coating approach for dye-sensitized solar cell. The most important three functions of the compact bilayer are reducing the recombination rate of electrons as a barrier layer, enlarging the utilization of sunlight as a luminescence material both with down- and up- conversions, and enhancing the long-term stability of the device as a defender of the dye. Besides, the construction of double layer with down- and up- conversion functions has no significant influence on giving rise to quenching effect. Furthermore, these findings offer potential applications for photovoltaic device with a wide range response of sunlight via the variation in rare-earth species and cell structures.

  20. Ultrashort Generation Regimes in the All-Fiber Kerr Mode-Locked Erbium-Doped Fiber Ring Laser for Terahertz Pulsed Spectroscopy

    Directory of Open Access Journals (Sweden)

    V. S. Voropaev

    2015-01-01

    Full Text Available Many femtosecond engineering applications require for a stable generation of ultrashort pulses. Thus, in the terahertz pulsed spectroscopy a measurement error in the refractive index is strongly dependent on the pulse duration stability with allowable variation of few femtoseconds. The aim of this work is to study the ultrashort pulses (USP regimes stability in the all – fiber erbium doped ring laser with Kerr mode-locking. The study was conducted at several different values of the total resonator intra-cavity dispersion. Three laser schemes with the intra-cavity dispersion values from -1.232 ps2 to +0.008 ps2 have been studied. In the experiment there were two regimes of generation observed: the stretched pulse generation and ordinary soliton generation. Main attention is focused on the stability of regimes under study. The most stable regime was that of the stretched pulse generation with a spectrum form of sech2 , possible pulse duration of 490 fs at least, repetition rate of 2.9 MHz, and average output power of 17 mW. It is worth noting, that obtained regimes had characteristics suitable for the successful use in the terahertz pulsed spectroscopy. The results may be useful in the following areas of science and technology: a high-precision spectroscopy, optical frequency standards, super-continuum generation, and terahertz pulsed spectroscopy. The future system development is expected to stabilize duration and repetition rate of the obtained regime of ultra-short pulse generation.

  1. Multi-soliton and rogue-wave solutions of the higher-order Hirota system for an erbium-doped nonlinear fiber

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Da-Wei [Beijing University of Aeronautics and Astronautics, Beijing (China). State Key Laboratory of Software Development Environment; Ministry of Education, Beijing (China). Key Laboratory of Fluid Mechanics; Shijiazhuang Tiedao University (China). Dept. of Mathematics and Physics; Gao, Yi-Tian; Sun, Yu-Hao; Feng, Yu-Jie; Xue, Long [Beijing University of Aeronautics and Astronautics, Beijing (China). State Key Laboratory of Software Development Environment; Ministry of Education, Beijing (China). Key Laboratory of Fluid Mechanics

    2014-10-15

    The nonlinear Schroedinger (NLS) equation appears in fluid mechanics, plasma physics, etc., while the Hirota equation, a higher-order NLS equation, has been introduced. In this paper, a higher-order Hirota system is investigated, which describes the wave propagation in an erbium-doped nonlinear fiber with higher-order dispersion. By virtue of the Darboux transformation and generalized Darboux transformation, multi-soliton solutions and higher-order rogue-wave solutions are derived, beyond the published first-order consideration. Wave propagation and interaction are analyzed: (i) Bell-shape solitons, bright- and dark-rogue waves are found; (ii) the two-soliton interaction is elastic, i.e., the amplitude and velocity of each soliton remain unchanged after the interaction; (iii) the coefficient in the system affects the direction of the soliton propagation, patterns of the soliton interaction, distance, and direction of the first-order rogue-wave propagation, as well as the range and direction of the second-order rogue-wave interaction.

  2. Switchable multi-wavelength erbium-doped fiber ring laser based on a tapered in-line Mach–Zehnder interferometer

    Science.gov (United States)

    Zhou, Yuxin; Wang, Xin; Tang, Zijuan; Lou, Shuqin

    2018-05-01

    In this paper, a switchable multi-wavelength erbium-doped fiber ring laser based on a tapered in-line Mach–Zehnder interferometer is proposed. The in-line Mach–Zehnder interferometer is fabricated by splicing a large-core fiber between two segments of single mode fibers, in which the first splicing point is tapered and the second splicing point is connected directly. By carefully rotating the polarization controller, switchable single-, dual-, triple- and quad-wavelength lasing outputs can be obtained with a side mode suppression ratio higher than 50 dB. The maximal peak power difference of multi-wavelength lasing is 3.67 dB, demonstrating a good power equalization performance. Furthermore, the proposed laser is proven to be very stable at room temperature. The wavelength shifts and peak power fluctuations are less than 0.02 nm and 1.3 dB over half an hour. In addition, stable quintuple-wavelength lasing with a side mode suppression ratio higher than 50 dB can also be realized when the filter length is changed.

  3. High-efficiency ytterbium-free erbium-doped all-glass double cladding silicate glass fiber for resonantly-pumped fiber lasers.

    Science.gov (United States)

    Qiang, Zexuan; Geng, Jihong; Luo, Tao; Zhang, Jun; Jiang, Shibin

    2014-02-01

    A highly efficient ytterbium-free erbium-doped silicate glass fiber has been developed for high-power fiber laser applications at an eye-safe wavelength near 1.55 μm. Our preliminary experiments show that high laser efficiency can be obtained from a relatively short length of the gain fiber when resonantly pumped at 1535 nm in both core- and cladding-pumping configurations. With a core-pumping configuration as high as 75%, optical-to-optical efficiency and 4 W output power were obtained at 1560 nm from a 1 m long gain fiber. When using a cladding-pumping configuration, approximately 13 W output power with 67.7% slope efficiency was demonstrated from a piece of 2 m long fiber. The lengths of silicate-based gain fiber are much shorter than their silica-based counterparts used in other experiments, which is significantly important for high-power narrow-band and/or pulsed laser applications.

  4. Unconventional cells of TiO2 doped with erbium; Celulas nao convencionais de TiO2 dopado com erbio

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, P.C.; Campos, R.D.; Oliveira, A.S.; Wellen, R., E-mail: pollyana@cear.ufpb.edu.br [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Diniz, V.C.S.; Costa, A.C.F.M. da [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais

    2016-07-01

    The technology used in TiO{sub 2} solar cells is in constant improvement, new configurations have been developed, aiming practicality and leading to efficiency increase of photovoltaic devices. This paper proposes a new technology for the production of solar cells in order to investigate a better utilization of solar spectrum of TiO2 doped with erbium (Er{sup 3+}), proven by energetic conversion. The Ti{sub 0,9}Er{sub 0,1}O2 system was obtained by Pechini method. Nanoparticles have a crystallite size 65.30 nm and surface area 118.48 m{sup 2}/g. These characteristics are essential for the formation of the film to be deposited on the conductive glass substrate constituting the cell's photoelectrode. The other side of the cell is the platinum counter electrode. The cell will have the faces sealed by a thermoplastic and, finally the electrolyte will be inserted, then they will be electrically evaluated through energy efficiency and confronted with the literature data base. (author)

  5. A high stability wavelength-tunable narrow-linewidth and single-polarization erbium-doped fiber laser using a compound-cavity structure

    International Nuclear Information System (INIS)

    Feng, Ting; Yan, Fengping; Peng, Wanjing; Liu, Shuo; Tan, Siyu; Liang, Xiao; Wen, Xiaodong

    2014-01-01

    A high stability wavelength-tunable narrow-linewidth and single-polarization erbium-doped fiber laser using a compound-cavity structure is proposed and demonstrated experimentally. The compound-cavity is composed of a main-linear-cavity and a subring-cavity. Using a pump power of 150 mW, the optical signal to noise ratio of the laser output is as high as ∼67 dB; the wavelength and output power fluctuation are 0.7 pm and 0.07 dBm respectively in an experimental period of 1 h; the linewidth of the laser output is as narrow as 650 Hz; the degree of polarization of the laser output is stable at a value of 100.8% in 15 min and the polarization extinction ratio is as high as 30.57 dB; the wavelength-tunable range is as wide as ∼8.1 nm. The proposed fiber laser can be used in areas where high stability, narrow-linewidth, single-polarization and wide wavelength-tunable range are needed. (letter)

  6. Solitons and rogue waves for a higher-order nonlinear Schroedinger-Maxwell-Bloch system in an erbium-doped fiber

    International Nuclear Information System (INIS)

    Su, Chuan-Qi; Gao, Yi-Tian; Yu, Xin; Xue, Long; Aviation Univ. of Air Force, Liaoning

    2015-01-01

    Under investigation in this article is a higher-order nonlinear Schroedinger-Maxwell-Bloch (HNLS-MB) system for the optical pulse propagation in an erbium-doped fiber. Lax pair, Darboux transformation (DT), and generalised DT for the HNLS-MB system are constructed. Soliton solutions and rogue wave solutions are derived based on the DT and generalised DT, respectively. Properties of the solitons and rogue waves are graphically presented. The third-order dispersion parameter, fourth-order dispersion parameter, and frequency detuning all influence the characteristic lines and velocities of the solitons. The frequency detuning also affects the amplitudes of solitons. The separating function has no effect on the properties of the first-order rogue waves, except for the locations where the first-order rogue waves appear. The third-order dispersion parameter affects the propagation directions and shapes of the rogue waves. The frequency detuning influences the rogue-wave types of the module for the measure of polarization of resonant medium and the extant population inversion. The fourth-order dispersion parameter impacts the rogue-wave interaction range and also has an effect on the rogue-wave type of the extant population inversion. The value of separating function affects the spatial-temporal separation of constituting elementary rogue waves for the second-order and third-order rogue waves. The second-order and third-order rogue waves can exhibit the triangular and pentagon patterns under different choices of separating functions.

  7. Tunable and switchable dual-wavelength single polarization narrow linewidth SLM erbium-doped fiber laser based on a PM-CMFBG filter.

    Science.gov (United States)

    Yin, Bin; Feng, Suchun; Liu, Zhibo; Bai, Yunlong; Jian, Shuisheng

    2014-09-22

    A tunable and switchable dual-wavelength single polarization narrow linewidth single-longitudinal-mode (SLM) erbium-doped fiber (EDF) ring laser based on polarization-maintaining chirped moiré fiber Bragg grating (PM-CMFBG) filter is proposed and demonstrated. For the first time as we know, the CMFBG inscribed on the PM fiber is applied for the wavelength-tunable and-switchable dual-wavelength laser. The PM-CMFBG filter with ultra-narrow transmission band (0.1 pm) and a uniform polarization-maintaining fiber Bragg grating (PM-FBG) are used to select the laser longitudinal mode. The stable single polarization SLM operation is guaranteed by the PM-CMFBG filter and polarization controller. A tuning range of about 0.25 nm with about 0.075 nm step is achieved by stretching the uniform PM-FBG. Meanwhile, the linewidth of the fiber laser for each wavelength is approximate 6.5 and 7.1 kHz with a 20 dB linewidth, which indicates the laser linewidth is approximate 325 Hz and 355 Hz FWHM.

  8. The study of 80 MHz self starting passively mode-locked Erbium-Doped Fiber Laser via nonlinear polarization rotation with SESAM

    International Nuclear Information System (INIS)

    Qamar, F.

    2013-01-01

    Erbium-Doped Fiber Laser, EDF L, passively mode-locked via only Nonlinear Polarization Rotation, NPR, and via NPR with Semiconductor Saturable Absorber Mirror, SESAM, is studied. Self start single pulse train with pulse width of 114 fs and repetition rate (PRR) of 80 MHz has been obtained when 55 cm EDFL, passively mode-locked via NPR only. Inserting SESAM in EDFL cavity leads to shorten the pulse width up to 88 fs, increases the amplitude stability up to 96% and lower the phase noise jittering to around 26 fsec. Stable second harmonic self starting passively mode-locked EDFL with pulse width of 284 fs has also been observed only when SESAM was used in the cavity. Multi-pulsed system passively mode-locked via NPR for EDFL length of 80 cm with time difference between the successive multi-pulses ranged from few picoseconds to nanoseconds, has been observed. The time difference can be controlled by the polarizer controller and the half wave plate. Further controlling of the cavity polarization leads to developing the multiple mode locking pulses train to second harmonic mode-locking pulse train with PRR of 160MHz and pulse width of 156 fs. Three harmonic superposed trains of mode locked pulse have been achieved only when SESAM added to the cavity. (author)

  9. Review of doped silica glass optical fibre: Their TL properties and potential applications in radiation therapy dosimetry

    International Nuclear Information System (INIS)

    Bradley, D.A.; Hugtenburg, R.P.; Nisbet, A.; Abdul Rahman, Ahmad Taufek; Issa, Fatma; Mohd Noor, Noramaliza; Alalawi, Amani

    2012-01-01

    Review is made of dosimetric studies of Ge-doped SiO 2 telecommunication fibre as a 1-D thermoluminescence (TL) system for therapeutic applications. To-date, the response of these fibres has been investigated for UV sources, superficial X-ray beam therapy facilities, a synchrotron microbeam facility, electron linear accelerators, protons, neutrons and alpha particles, covering the energy range from a few eV to several MeV. Dosimetric characteristics include, reproducibility, fading, dose response, reciprocity between TL yield and dose-rate and energy dependence. The fibres produce a flat response to fixed photon and electron doses to within better than 3% of the mean TL distribution. Irradiated Ge-doped SiO 2 optical fibres show limited signal fading, with an average loss of TL signal of ∼0.4% per day. In terms of dose response, Ge-doped SiO 2 optical fibres have been shown to provide linearity to x and electron doses, from a fraction of 1 Gy up to 2 kGy. The dosimeters have also been used in measuring photoelectron generation from iodinated contrast media; TL yields being some 60% greater in the presence of iodine than in its absence. The review is accompanied by previously unpublished data. - Highlights: ► We review our TLD studies of Ge-doped SiO 2 fibres for therapeutic applications. ► Sources include UV, X-rays, protons, neutrons and alpha particles. ► These TLDs have also been used to measure photoelectrons from I 2 contrast media. ► The review is accompanied by previously unpublished data.

  10. Synthesis and thermoluminescent characterization of lithium niobate doped with erbium; Sintesis y caracterizacion termoluminiscente de niobato de litio impurificado con erbio

    Energy Technology Data Exchange (ETDEWEB)

    Landavazo, M.; Brown, F.; Cubillas, F. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Blvd. Luis Encinas y Rosales s/n, 83000 Hermosillo, Sonora (Mexico); Munoz, I. [Universidad de Sonora, Departamento de Ciencias Quimico Biologicas, 83000 Hermosillo, Sonora (Mexico); Cruz Z, E., E-mail: imunoz@polimeros.uson.mx [UNAM, Instituto de Ciencias Nucleares, Apdo. Postal 70-543, 04510 Mexico D. F. (Mexico)

    2015-10-15

    Full text: Lithium niobate (Nl) is a synthetic dielectric and is mainly used in optical devices. There are reports on the thermoluminescent property of Nl monocrystals doped with rare earths and excited with X and gamma rays. In this study the Nl was synthesized and doped with erbium (Er) at concentrations of 1, 2 and 4 % mol and was characterized by its Tl property. The synthesis was realized by solid state reaction at 1000 degrees C for 22 hours and the formation of Nl:Er was confirmed by X-ray diffraction, scanning electron microscopy and EDS analysis, finding a new phase (ErNbO{sub 4}). Was studied the dose-response gamma in a range of 1-1000 Gy, the material showed linear behavior of 1-600 Gy. The brightness curves have maxima at 185 and 285 degrees C to 1% in 183 and 301 degrees C for 2%, respectively. While for the concentration of 4% a maximum in 177 degrees C accompanied by a smaller peak at higher temperature of the glow curve was observed. The Tl response of Nl:Er 4% to 450 Gy was increased 271 times compared to pure Nl. The reproducibility of the Tl signal at ten cycles of irradiation-reading, present a standard deviation of 5%. In Nl:Er 1% Tl signal fades in 21.3% after 24 hours, while in 2 and 4% an unusual fading occurs. The Tl characteristics of Nl:Er synthesized material is of interest to gamma radiation dosimetry of high doses. (Author)

  11. Electrospinning preparation and photophysical properties of one-dimensional (1D) composite nanofibers doped with erbium(III) complexes

    International Nuclear Information System (INIS)

    Sun Xu; Li Bin; Song Luting; Gong Jian; Zhang Liming

    2010-01-01

    1D composite nanofibers of poly(vinylpyrrolidone) (PVP, M W ∼60,000) doped with three Er(III) complexes were prepared by electrospinning. They demonstrated strong near-infrared (NIR) photoluminescence (PL) at 1535 nm and ternary Er(TTA) 3 Phen (denoted as Er2, where TTA=2-thenoyltrifluoroacetonate; Phen=1,10-phenanthroline) fibers (Er2/PVP) exhibited maximum PL intensity. The crystal structure of Er2 complex has been determined by X-ray diffraction measurements. Er2 doped in fibers exhibited better thermal stability of NIR PL than the pure Er2 complex. These luminescent composite fibers have potential application in optical amplifiers.

  12. A comparative scanning electron microscopy study between hand instrument, ultrasonic scaling and erbium doped:Yttirum aluminum garnet laser on root surface: A morphological and thermal analysis

    Directory of Open Access Journals (Sweden)

    Mitul Kumar Mishra

    2013-01-01

    Full Text Available Background and Objectives: Scaling and root planing is one of the most commonly used procedures for the treatment of periodontal diseases. Removal of calculus using conventional hand instruments is incomplete and rather time consuming. In search of more efficient and less difficult instrumentation, investigators have proposed lasers as an alternative or as adjuncts to scaling and root planing. Hence, the purpose of the present study was to evaluate the effectiveness of erbium doped: Yttirum aluminum garnet (Er:YAG laser scaling and root planing alone or as an adjunct to hand and ultrasonic instrumentation. Subjects and Methods: A total of 75 freshly extracted periodontally involved single rooted teeth were collected. Teeth were randomly divided into five treatment groups having 15 teeth each: Hand scaling only, ultrasonic scaling only, Er:YAG laser scaling only, hand scaling + Er:YAG laser scaling and ultrasonic scaling + Er:YAG laser scaling. Specimens were subjected to scanning electron microscopy and photographs were evaluated by three examiners who were blinded to the study. Parameters included were remaining calculus index, loss of tooth substance index, roughness loss of tooth substance index, presence or absence of smear layer, thermal damage and any other morphological damage. Results: Er:YAG laser treated specimens showed similar effectiveness in calculus removal to the other test groups whereas tooth substance loss and tooth surface roughness was more on comparison with other groups. Ultrasonic treated specimens showed better results as compared to other groups with different parameters. However, smear layer presence was seen more with hand and ultrasonic groups. Very few laser treated specimens showed thermal damage and morphological change. Interpretation and Conclusion: In our study, ultrasonic scaling specimen have shown root surface clean and practically unaltered. On the other hand, hand instrument have produced a plane surface

  13. Effect of Ga2O3 on the spectroscopic properties of erbium-doped boro-bismuth glasses.

    Science.gov (United States)

    Ling, Zhou; Ya-Xun, Zhou; Shi-Xun, Dai; Tie-Feng, Xu; Qiu-Hua, Nie; Xiang, Shen

    2007-11-01

    The spectroscopic properties and thermal stability of Er3+-doped Bi2O3-B2O3-Ga2O3 glasses are investigated experimentally. The effect of Ga2O3 content on absorption spectra, the Judd-Ofelt parameters Omega t (t=2, 4, 6), fluorescence spectra and the lifetimes of Er3+:4I 13/2 level are also investigated, and the stimulated emission cross-section is calculated from McCumber theory. With the increasing of Ga2O3 content in the glass composition, the Omega t (t=2, 4, 6) parameters, fluorescence full width at half maximum (FWHM) and the 4I 13/2 lifetimes of Er3+ first increase, reach its maximum at Ga2O3=8 mol.%, and then decrease. The results show that Er3+-doped 50Bi2O3-42B2O3-8Ga2O3 glass has the broadest FWHM (81nm) and large stimulated emission cross-section (1.03 x1 0(-20)cm2) in these glass samples. Compared with other glass hosts, the gain bandwidth properties of Er+3-doped Bi2O3-B2O3-Ga2O3 glass is better than tellurite, silicate, phosphate and germante glasses. In addition, the lifetime of 4I 13/2 level of Er(3+) in bismuth-based glass, compared with those in other glasses, is relative low due to the high-phonon energy of the B-O bond, the large refractive index of the host and the existence of OH* in the glass. At the same time, the glass thermal stability is improved in which the substitution of Ga2O3 for B2O3 strengthens the network structure. The suitability of bismuth-based glass as a host for a Er3+-doped broadband amplifier and its advantages over other glass hosts are also discussed.

  14. Charge-transfer state excitation as the main mechanism of the photodarkening process in ytterbium-doped aluminosilicate fibres

    Energy Technology Data Exchange (ETDEWEB)

    Bobkov, K K; Rybaltovsky, A A; Vel' miskin, V V; Likhachev, M E; Bubnov, M M; Dianov, E M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Umnikov, A A; Gur' yanov, A N; Vechkanov, N N [G.G.Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation); Shestakova, I A [Open Joint-Stock Company M.F. Stel' makh Polyus Research Institute, Moscow (Russian Federation)

    2014-12-31

    We have studied photodarkening in ytterbium-doped fibre preforms with an aluminosilicate glass core. Analysis of their absorption and luminescence spectra indicates the formation of stable Yb{sup 2+} ions in the glass network under IR laser pumping at a wavelength λ = 915 nm and under UV irradiation with an excimer laser (λ = 193 nm). We have performed comparative studies of the luminescence spectra of the preforms and crystals under excitation at a wavelength of 193 nm. The mechanism behind the formation of Yb{sup 2+} ions and aluminium – oxygen hole centres (Al-OHCs), common to ytterbium-doped YAG crystals and aluminosilicate glass, has been identified: photoinduced Yb{sup 3+} charge-transfer state excitation. (optical fibres)

  15. Thermoluminescence glow curve analysis and CGCD method for erbium doped CaZrO{sub 3} phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Ratnesh, E-mail: 31rati@gmail.com [Department of Physics, Bhilai Institute of Technology, Raipur, 493661 (India); Chopra, Seema [Department Physics, G.D Goenka Public School (India)

    2016-05-06

    The manuscript report the synthesis, thermoluminescence study at fixed concentration of Er{sup 3+} (1 mol%) doped CaZrO{sub 3} phosphor. The phosphors were prepared by modified solid state reaction method. The powder sample was characterized by thermoluminescence (TL) glow curve analysis. In TL glow curve the optimized concentration in 1mol% for UV irradiated sample. The kinetic parameters were calculated by computerized glow curve deconvolution (CGCD) techniaue. Trapping parameters gives the information of dosimetry loss in prepared phosphor and its usability in environmental monitoring and for personal monitoring. CGCD is the advance tool for analysis of complicated TL glow curves.

  16. Micro Extrinsic Fiber-Optic Fabry-Perot Interferometric Sensor Based on Erbium- and Boron-Doped Fibers

    International Nuclear Information System (INIS)

    Yun-Jiang, Rao; Bing, Xu; Zeng-Ling, Ran; Yuan, Gong

    2010-01-01

    Micro extrinsic Fabry–Perot interferometers (MEFPIs), with cavity lengths of up to ∼ 9 μm and maximum fringe contrast of ∼ 19 dB, are fabricated by chemically etching Er- and B-doped optical fibers and then splicing the etched fiber to a single-mode fiber, for the first time to the best of our knowledge. The strain and temperature responses of the MEFPI sensors are investigated experimentally. Good linearity and high sensitivity are achieved. Such a type of MEFPI sensor is cost-effective and suitable for mass production, indicating its great potential for a wide range of applications. (fundamental areas of phenomenology(including applications))

  17. Design of DFB fibre lasers

    DEFF Research Database (Denmark)

    Lauridsen, Vibeke Claudia; Povlsen, Jørn Hedegaard; Varming, Poul

    1998-01-01

    A numerical model for erbium distributed feedback (DFB) fibre lasers is presented. The model is used to optimise the location of a discrete phase-shift to obtain maximum output power. For DFB fibre lasers of up to 10cm in length it is shown that the influence of Kerr nonlinearity with respect to ...... to output power is negligible....

  18. Experimental demonstration of the switching dose-rate method on doped optical fibers

    Science.gov (United States)

    Thomas, J.; Myara, M.; Troussellier, L.; Régnier, E.; Burov, E.; Gilard, O.; Sottom, M.; Signoret, P.

    2017-11-01

    Optical technology developed for ground and submarine telecommunications is becoming of strong interest for next generation satellites. In addition to inter-satellite laser communications and LIDAR's, new applications are being considered such as on-board distribution and processing of microwave signals, fiber sensors or gyroscopes as well. Whereas common optical / optoelectronic components are known to be weakly sensitive to radiations, the essential optical amplifiers are strongly degraded in such an environment because of the RIA (Radio-Induced-Absorption) experienced by the Erbium-Doped Fiber (EDF) itself [1-3]. This degradation is mainly caused by the presence of co-doping ions, such as Aluminium or Germanium, inserted in the fibre to assist the inclusion of the Erbium ions in the silica matrix or to provide to the optical fibre its guiding properties.

  19. Properties of Erbium Doped Hydrogenated Amorphous Carbon Layers Fabricated by Sputtering and Plasma Assisted Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    V. Prajzler

    2008-01-01

    Full Text Available We report about properties of carbon layers doped with Er3+ ions fabricated by Plasma Assisted Chemical Vapor Deposition (PACVD and by sputtering on silicon or glass substrates. The structure of the samples was characterized by X-ray diffraction and their composition was determined by Rutherford Backscattering Spectroscopy and Elastic Recoil Detection Analysis. The Absorbance spectrum was taken in the spectral range from 400 nm to 600 nm. Photoluminescence spectra were obtained using two types of Ar laser (λex=514.5 nm, lex=488 nm and also using a semiconductor laser (λex=980 nm. Samples fabricated by magnetron sputtering exhibited typical emission at 1530 nm when pumped at 514.5 nm. 

  20. Analysis of energy transfer process based emission spectra of erbium doped germanate glasses for mid-infrared laser materials

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Muzhi; Wei, Tao; Zhou, Beier; Tian, Ying; Zhou, Jiajia; Xu, Shiqing, E-mail: shiqingxu@cjlu.edu.cn; Zhang, Junjie, E-mail: jjzhang@cjlu.edu.cn

    2015-03-25

    Highlights: • Er{sup 3+} doped germanate glass with good thermal stability were prepared. • Ionic boding nature was proved by bonding parameter calculation. • Mid-infrared fluorescent behaviors and energy transfer were investigated. • Rate equation and Dexter’s theory were utilized to elucidate 2.7 μm emission. - Abstract: Er{sup 3+} activated germanate glass with good thermal stability was prepared. Bonding parameters have been calculated and the nature of ionic bonding of the germanate glass has been determined. Mid-infrared fluorescence was observed and corresponding radiative properties were investigated. For Er{sup 3+}:{sup 4}I{sub 11/2}→{sup 4}I{sub 13/2} transition, high spontaneous radiative transition probability (30.09 s{sup −1}), large emission cross section ((14.84 ± 0.10) × 10{sup −21} cm{sup 2}) and superior gain performance were obtained from the prepared glass. Besides, energy transfer processes concerning the 2.7 μm emission were also discussed in detail. According to simplified rate equation and Dexter’s theory, energy transfer microscopic parameters were computed to elucidate observed 2.7 μm emissions. Results demonstrate that the prepared germanate glass possessing excellent spectroscopic properties might be an attractive candidate for mid-infrared laser or amplifier.

  1. Analysis of energy transfer process based emission spectra of erbium doped germanate glasses for mid-infrared laser materials

    International Nuclear Information System (INIS)

    Cai, Muzhi; Wei, Tao; Zhou, Beier; Tian, Ying; Zhou, Jiajia; Xu, Shiqing; Zhang, Junjie

    2015-01-01

    Highlights: • Er 3+ doped germanate glass with good thermal stability were prepared. • Ionic boding nature was proved by bonding parameter calculation. • Mid-infrared fluorescent behaviors and energy transfer were investigated. • Rate equation and Dexter’s theory were utilized to elucidate 2.7 μm emission. - Abstract: Er 3+ activated germanate glass with good thermal stability was prepared. Bonding parameters have been calculated and the nature of ionic bonding of the germanate glass has been determined. Mid-infrared fluorescence was observed and corresponding radiative properties were investigated. For Er 3+ : 4 I 11/2 → 4 I 13/2 transition, high spontaneous radiative transition probability (30.09 s −1 ), large emission cross section ((14.84 ± 0.10) × 10 −21 cm 2 ) and superior gain performance were obtained from the prepared glass. Besides, energy transfer processes concerning the 2.7 μm emission were also discussed in detail. According to simplified rate equation and Dexter’s theory, energy transfer microscopic parameters were computed to elucidate observed 2.7 μm emissions. Results demonstrate that the prepared germanate glass possessing excellent spectroscopic properties might be an attractive candidate for mid-infrared laser or amplifier

  2. Reflective variable optical attenuators and fibre ring lasers for wavelength-division multiplexing systems

    Science.gov (United States)

    Liu, He Liang

    Wavelength division multiplexing (WDM) optical fibre system is an important enabling technology to fulfill the demands for bandwidth in the modern information age. The main objective of this project is to study novel devices with the potential to enhance the performance of WDM systems. In particular, a novel reflective variable optical attenuator (RVOA) used for dynamic gain equalization (DGE) and fibre lasers based on an entirely new type of erbium-doped fibres with ultrawide tuning range were investigated theoretically and experimentally. We proposed a new type of RVOA device which could be potentially integrated with arrayed waveguide grating (AWG) to reduce the cost of DGE substantially. Initially, fibre-based RVOAs, fabricated with optical fibre components such as fibre coupler and Faraday rotator mirror, were investigated theoretically and experimentally. Larger attenuation range up to 22 dB was realized for fibre coupler-based ROVA with a Faraday rotator mirror and its polarization-dependent loss is about 0.5 dB. Then polymeric waveguide-based RVOAs were investigated theoretically and experimentally. Using an epoxy Novolak resin as core material and an UV-cured resin (Norland's NOA61) as cladding material, a polymeric waveguide RVOA was successfully fabricated. The dynamic 15 dB attenuation range was achieved and the PDL was less than 0.2 dB. The measured insertion loss of the polymeric waveguide RVOA was too large (about 18 dB) and was mainly induced by coupling loss, material loss and poor alignment. In the second part of the study, fibre ring lasers with continuous wavelength tuning over wide wavelength range and fibre ring lasers with discrete wavelength tuning were investigated. Tunable lasers are important devices in WDM systems because they could be employed as reserved sources and therefore avoiding the need to stock large inventory of lasers to cover the ITU-wavelength grid. In this project, erbium ions doped bismuth oxide glass fibres instead of

  3. Nanoscale charcoal powder induced saturable absorption and mode-locking of a low-gain erbium-doped fiber-ring laser

    International Nuclear Information System (INIS)

    Lin, Yung-Hsiang; Chi, Yu-Chieh; Lin, Gong-Ru

    2013-01-01

    Triturated charcoal nano-powder directly brushed on a fiber connector end-face is used for the first time as a fast saturable absorber for a passively mode-locked erbium-doped fiber-ring laser (EDFL). These dispersant-free charcoal nano-powders with a small amount of crystalline graphene phase and highly disordered carbon structure exhibit a broadened x-ray diffraction peak and their Raman spectrum shows the existence of a carbon related D-band at 1350 cm −1 and the disappearance of the 2D-band peak at 2700 cm −1 . The charcoal nano-powder exhibits a featureless linear absorbance in the infrared region with its linear transmittance of 0.66 nonlinearly saturated at 0.73 to give a ΔT/T of 10%. Picosecond mode-locking at a transform-limited condition of a low-gain EDFL is obtained by using the charcoal nano-powder. By using a commercial EDFA with a linear gain of only 17 dB at the saturated output power of 17.5 dB m required to initiate the saturable absorption of the charcoal nano-powder, the EDFL provides a pulsewidth narrowing from 3.3 to 1.36 ps associated with its spectral linewidth broadening from 0.8 to 1.83 nm on increasing the feedback ratio from 30 to 90%. This investigation indicates that all the carbon-based materials containing a crystalline graphene phase can be employed to passively mode-lock the EDFL, however, the disordered carbon structure inevitably induces a small modulation depth and a large mode-locking threshold, thus limiting the pulsewidth shortening. Nevertheless, the nanoscale charcoal passively mode-locked EDFL still shows the potential to generate picosecond pulses under a relatively low cavity gain. An appropriate cavity design can be used to compensate this defect-induced pulsewidth limitation and obtain a short pulsewidth. (letter)

  4. Theoretical modelling of dual-wavelength pumped Yb3+–Tm3+ co-doped silica fibre laser

    International Nuclear Information System (INIS)

    Fu, Yuqing; Chen, Jianguo

    2010-01-01

    Numerical simulations have, for the first time to our knowledge, been carried out to characterize the Yb 3+ –Tm 3+ co-doped silica fibre laser (YTFL), defined by a fibre grating and an end mirror, by using the rate equations, which take into consideration both the energy transfer processes from Yb 3+ to Tm 3+ ions and the cross-relaxation processes among different Tm 3+ ions. A dual-wavelength pumping scheme with one at 805 nm and the other at 975 nm is used to pump the YTFL. We have investigated the wavelength-dependent output power of the YTFL, from 1750 to 2200 nm, which takes its maximum output power at ∼ 1800 nm. The effect of the cross-relaxation processes in the Tm 3+ -doped silica fibre laser has been studied. The results indicate that these processes are beneficial to the laser and should be considered in the theoretical modelling. The influence of the Yb 3+ concentration on the characteristics of the YTFL has also been analysed and the results show that Yb 3+ dopants can improve the output power and slope efficiency of the laser

  5. Design of distributed feedback fibre lasers

    DEFF Research Database (Denmark)

    Lauridsen, Vibeke Claudia; Søndergaard, Thomas; Varming, Poul

    1997-01-01

    A numerical model for erbium fibre lasers with Bragg gratings is presented. The model is used to optimize the location of a discrete phase-shift and the phase-shift magnitude for a distributed phase-shift.......A numerical model for erbium fibre lasers with Bragg gratings is presented. The model is used to optimize the location of a discrete phase-shift and the phase-shift magnitude for a distributed phase-shift....

  6. Seven-core active fibre for application in telecommunication satellites

    Science.gov (United States)

    Filipowicz, Marta; Napierała, Marek; Murawski, Michał; Ostrowski, Łukasz; Szostkiewicz, Łukasz; Szymański, Michał; Tenderenda, Tadeusz; Anders, Krzysztof; Piramidowicz, Ryszard; Wójcik, Grzegorz; Makara, Mariusz; Poturaj, Krzysztof; Mergo, Paweł; Nasiłowski, Tomasz

    2015-12-01

    The use of optical elements and other photonic components makes it possible to overcome telecommunication satellite's bottleneck problems such as size and weight reduction. Despite the unquestionable potential of such elements, nowadays they are not widely used in systems operating in space. This is due to many factors, including the fact that space radiation has disruptive influence on optical fibre. Namely it introduces additional radiation induced attenuation (RIA) that significantly lowers efficiency of optical fibre based systems. However, there is a possibility to produce radiation-hardened (rad-hard) components. One of them is seven core erbium-doped active fibre (MC-EDF) for fibre amplifiers in satellites that we have been developing. In this paper we present a detailed description of seven core structure design as well as experimental results. We report that average gain of 20 dB in C-band with noise figure of 5.8 dB was obtained. We also confirmed that low crosstalk value for a multicore fibre amplifier based on our fibre can be achieved.

  7. Study of doping non-PMMA polymer fibre canes with UV photosensitive compounds

    DEFF Research Database (Denmark)

    Hassan, Hafeez Ul; Fasano, Andrea; Janting, Jakob

    2016-01-01

    and hollow-core TOPAS canes were doped with a solution of dopants in acetone/methanol and hexane/methanol, respectively. Doping time, solvent mixture concentration and doping temperature were optimised. A long and stepwise drying process was applied to the doped canes to ensure complete solvent removal...

  8. Multimode laser emission from dye-doped hollow polymer optical fibre

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Fibre lasers; optical microcavities; whispering gallery modes. ... A blueshift in the mode structure was observed with decrease in fibre diameter leading to wide range tunability of the laser emission. ... International School of Photonics, Cochin University of Science & Technology, Cochin 682 022, India ...

  9. Rare-Earth Oxide Ion (Tm3+, Ho3+, and U3+) Doped Glasses and Fibres for 1.8 to 4 Micrometer Coherent and Broadband Sources

    Science.gov (United States)

    2006-07-24

    oxide ( TeO2 ) , fluorine- containing silicate (SiOF2) and germanate (GeOF2) glass hosts for each dopant by characterising the spectroscopic properties...Earth Oxide Ion (Tm3+, Ho3+, And U3+) Doped Glasses And Fibres For 1.8 To 4 Micrometer Coherent And Broadband Sources 5c. PROGRAM ELEMENT NUMBER 5d...Rare-earth oxide ion (Tm3+, Ho3+, and U3+) doped glasses and fibres for 1.8 to 4 micrometer coherent and broadband sources Report prepared

  10. Development of tungsten fibre-reinforced tungsten composites towards their use in DEMO—potassium doped tungsten wire

    Science.gov (United States)

    Riesch, J.; Han, Y.; Almanstötter, J.; Coenen, J. W.; Höschen, T.; Jasper, B.; Zhao, P.; Linsmeier, Ch; Neu, R.

    2016-02-01

    For the next step fusion reactor the use of tungsten is inevitable to suppress erosion and allow operation at elevated temperature and high heat loads. Tungsten fibre-reinforced composites overcome the intrinsic brittleness of tungsten and its susceptibility to operation embrittlement and thus allow its use as a structural as well as an armour material. That this concept works in principle has been shown in recent years. In this contribution we present a development approach towards its use in a future fusion reactor. A multilayer approach is needed addressing all composite constituents and manufacturing steps. A huge potential lies in the optimization of the tungsten wire used as fibre. We discuss this aspect and present studies on potassium doped tungsten wire in detail. This wire, utilized in the illumination industry, could be a replacement for the so far used pure tungsten wire due to its superior high temperature properties. In tensile tests the wire showed high strength and ductility up to an annealing temperature of 2200 K. The results show that the use of doped tungsten wire could increase the allowed fabrication temperature and the overall working temperature of the composite itself.

  11. Development of tungsten fibre-reinforced tungsten composites towards their use in DEMO—potassium doped tungsten wire

    International Nuclear Information System (INIS)

    Riesch, J; Han, Y; Höschen, T; Zhao, P; Neu, R; Almanstötter, J; Coenen, J W; Jasper, B; Linsmeier, Ch

    2016-01-01

    For the next step fusion reactor the use of tungsten is inevitable to suppress erosion and allow operation at elevated temperature and high heat loads. Tungsten fibre-reinforced composites overcome the intrinsic brittleness of tungsten and its susceptibility to operation embrittlement and thus allow its use as a structural as well as an armour material. That this concept works in principle has been shown in recent years. In this contribution we present a development approach towards its use in a future fusion reactor. A multilayer approach is needed addressing all composite constituents and manufacturing steps. A huge potential lies in the optimization of the tungsten wire used as fibre. We discuss this aspect and present studies on potassium doped tungsten wire in detail. This wire, utilized in the illumination industry, could be a replacement for the so far used pure tungsten wire due to its superior high temperature properties. In tensile tests the wire showed high strength and ductility up to an annealing temperature of 2200 K. The results show that the use of doped tungsten wire could increase the allowed fabrication temperature and the overall working temperature of the composite itself. (paper)

  12. Synthesis and characterization of erbium-doped SiO{sub 2}-TiO{sub 2} thin films prepared by sol-gel and dip-coating techniques onto commercial glass substrates as a route for obtaining active GRadient-INdex materials

    Energy Technology Data Exchange (ETDEWEB)

    Gómez-Varela, Ana I. [Microoptics and GRIN Optics Group, Department of Applied Physics, Faculty of Optics and Optometry and Faculty of Physics, Universidade de Santiago de Compostela, Campus Vida s/n, Santiago de Compostela E-15782 (Spain); Castro, Yolanda, E-mail: castro@icv.csic.es [Instituto de Cerámica y Vidrio (CSIC), Kelsen 5, Campus de Cantoblanco, Madrid 28049 (Spain); Durán, Alicia [Instituto de Cerámica y Vidrio (CSIC), Kelsen 5, Campus de Cantoblanco, Madrid 28049 (Spain); De Beule, Pieter A.A. [Applied Nano-Optics Laboratory, International Iberian Nanotechnology Laboratory, Braga 4715-330 (Portugal); Flores-Arias, María T. [Microoptics and GRIN Optics Group, Department of Applied Physics, Faculty of Optics and Optometry and Faculty of Physics, Universidade de Santiago de Compostela, Campus Vida s/n, Santiago de Compostela E-15782 (Spain); Bao-Varela, Carmen, E-mail: carmen.bao@usc.es [Microoptics and GRIN Optics Group, Department of Applied Physics, Faculty of Optics and Optometry and Faculty of Physics, Universidade de Santiago de Compostela, Campus Vida s/n, Santiago de Compostela E-15782 (Spain)

    2015-05-29

    In this work, SiO{sub 2}-TiO{sub 2} films doped with erbium were prepared by dip-coating sol-gel process onto commercial glass substrates. The surface morphology of the films was characterized using atomic force microscopy, while thickness, refractive index, extinction coefficient and porosity of the films were determined by ellipsometric measurements in a wavelength region of 400-1000 nm. Optical constants and porosity were found to vary with erbium concentration. The proof of principle presented in this paper is applicable to systems of different nature by tailoring the sol-gel precursors in such a way that active GRadient-INdex media described by a complex, parabolic-like refractive index distribution for beam shaping purposes is obtained. - Highlights: • Sol-gel route for preparation of active GRadient-INdex materials is proposed. • SiO{sub 2}-TiO{sub 2} films doped with erbium were prepared by dipping onto commercial glasses. • Morphological and optical characterization of the samples was performed. • Optical constants and porosity were found to vary with erbium concentration. • Refractive index diminishes with dopant content; the contrary occurs for porosity.

  13. Synthesis and characterization of erbium-doped SiO2-TiO2 thin films prepared by sol-gel and dip-coating techniques onto commercial glass substrates as a route for obtaining active GRadient-INdex materials

    International Nuclear Information System (INIS)

    Gómez-Varela, Ana I.; Castro, Yolanda; Durán, Alicia; De Beule, Pieter A.A.; Flores-Arias, María T.; Bao-Varela, Carmen

    2015-01-01

    In this work, SiO 2 -TiO 2 films doped with erbium were prepared by dip-coating sol-gel process onto commercial glass substrates. The surface morphology of the films was characterized using atomic force microscopy, while thickness, refractive index, extinction coefficient and porosity of the films were determined by ellipsometric measurements in a wavelength region of 400-1000 nm. Optical constants and porosity were found to vary with erbium concentration. The proof of principle presented in this paper is applicable to systems of different nature by tailoring the sol-gel precursors in such a way that active GRadient-INdex media described by a complex, parabolic-like refractive index distribution for beam shaping purposes is obtained. - Highlights: • Sol-gel route for preparation of active GRadient-INdex materials is proposed. • SiO 2 -TiO 2 films doped with erbium were prepared by dipping onto commercial glasses. • Morphological and optical characterization of the samples was performed. • Optical constants and porosity were found to vary with erbium concentration. • Refractive index diminishes with dopant content; the contrary occurs for porosity

  14. Comparison of two Q-switched lasers and a short-pulse erbium-doped yttrium aluminum garnet laser for treatment of cosmetic tattoos containing titanium and iron in an animal model.

    Science.gov (United States)

    Wang, Chia-Chen; Huang, Chuen-Lin; Yang, An-Hang; Chen, Chih-Kang; Lee, Shao-Chen; Leu, Fur-Jiang

    2010-11-01

    Cosmetic tattoos contain titanium and ferric oxide and darken through reduction after Q-switched laser irradiation. The optimal treatment for removing these pigments remains unknown. To compare the effects of two Q-switched lasers and a short-pulse erbium-doped yttrium aluminum garnet (SP Er:YAG) laser to remove cosmetic tattoos in an animal model. Rats were tattooed using white, flesh-colored, and brown inks (4 bands of each color) on their backs. For each color, one band was left untreated, and one each was treated with a Q-switched neodymium-doped YAG laser, a Q-switched alexandrite laser, and a SP Er:YAG laser every 3 weeks until the pigments were clear. The two Q-switched lasers were equally effective; all three pigments darkened initially and then resolved gradually. Up to 20, 18, and 10 sessions were required to remove white, flesh-colored, and brown tattoos, respectively. Only six sessions were required with the SP Er:YAG laser. Minimal scarring was observed with all lasers. Skin biopsies confirmed pigment granule fragmentation after Q-switched laser treatment and a decrease in the amount of pigment after SP Er:YAG laser treatment. The SP Er:YAG laser was superior to the Q-switched lasers for removing cosmetic tattoos. © 2010 by the American Society for Dermatologic Surgery, Inc.

  15. Erbium diffusion from erbium metal or erbium oxide layers deposited on the surface of various LiNbO3 cuts

    Czech Academy of Sciences Publication Activity Database

    Nekvindová, P.; Cajzl, J.; Švecová, B.; Macková, Anna; Malinský, Petr; Oswald, Jiří; Vacík, Jiří; Spirkova, J.

    2013-01-01

    Roč. 36, č. 2 (2013), s. 402-407 ISSN 0925-3467 R&D Projects: GA ČR(CZ) GAP106/10/1477; GA ČR GA106/09/0125; GA MŠk(XE) LM2011019; GA TA ČR TA01010237 Institutional support: RVO:68378271 ; RVO:61389005 Keywords : lithium niobate * erbium * erbium oxide * diffusion doping * luminescent materials Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders; BM - Solid Matter Physics ; Magnetism (FZU-D) Impact factor: 2.075, year: 2013

  16. Polarisation effects in fibre lasers

    OpenAIRE

    Lin, J.T.; Morkel, P.R.; Reekie, L.; Payne, D.N.

    1987-01-01

    Two orthogonal polarisation eigenmodes have been observed in a single-mode fibre laser. Experimental investigation shows good agreement with theoretical analysis. Both Nd3+ and Er3+-doped single-polarisation single-mode fibre lasers have been demonstrated

  17. An investigation of the thermoluminescence of Ge-doped SiO2 optical fibres for application in interface radiation dosimetry

    International Nuclear Information System (INIS)

    Abdul Rahman, A.T.; Hugtenburg, R.P.; Abdul Sani, Siti Fairus; Alalawi, A.I.M.; Issa, Fatma; Thomas, R.; Barry, M.A.; Nisbet, A.; Bradley, D.A.

    2012-01-01

    We investigate the ability of high spatial resolution (∼ 120 μm) Ge-doped SiO 2 TL dosimeters to measure photoelectron dose enhancement resulting from the use of a moderate to high-Z target (an iodinated contrast media) irradiated by 90 kVp X-rays. We imagine its application in a novel radiation synovectomy technique, modelled by a phantom containing a reservoir of I 2 molecules at the interface of which the doped silica dosimeters are located. Measurements outside of the iodine photoelectron range are provided for using a stepped-design that allows insertion of the fibres within the phantom. Monte Carlo simulation (MCNPX) is used for verification. At the phantom medium I 2 -interface additional photoelectron generation is observed, ∼60% above that in the absence of the I 2 , simulations providing agreement to within 3%. Percentage depth doses measured away from the iodine contrast medium reservoir are bounded by published PDDs at 80 kVp and 100 kVp. - Highlights: ▶ Studies of dosimetric characteristic of commercially available doped silica optical fibres. ▶ Investigation of the potential of the dosimeter in dose enhancement measurement. ▶ Use of photoelectron dose enhancement as might be applied in radiation synovectomy. ▶ Measurement of the percentage depth dose recorded by Ge-doped silica optical fibres. ▶ The Monte Carlo simulation provides comparison against measured data.

  18. Single-frequency thulium-doped distributed-feedback fibre laser

    DEFF Research Database (Denmark)

    Agger, Søren; Povlsen, Jørn Hedegaard; Varming, Poul

    2004-01-01

    We have successfully demonstrated a single-frequency distributed-feedback (DFB) thulium-doped silica fiber laser emitting at a wavelength of 1735 nm. The laser cavity is less than 5 cm long and is formed by intracore UV-written Bragg gratings with a phase shift. The laser is pumped at 790 nm from...... a Ti:sapphire laser and has a threshold pump power of 59 mW. The laser has a maximum output power of 1 mW in a singlefrequency, single-polarization radiation mode and is tunable over a few nanometers. To the best of the authors’ knowledge, this is the first report of a single-frequency DFB fiber laser...... that uses thulium as the amplifying medium. The lasing wavelength is the longest demonstrated with DFB fiber lasers and yet is among the shortest obtained for thulium-doped silica fiber lasers....

  19. Micro-joule pico-second range Yb3+-doped fibre laser for medical applications in acupuncture

    Science.gov (United States)

    Alvarez-Chavez, J. A.; Rivera-Manrique, S. I.; Jacques, S. L.

    2011-08-01

    The work described here is based on the optical design, simulation and on-going implementation of a pulsed (Q-switch) Yb3+-doped, 1-um diffraction-limited fibre laser with pico-second, 10 micro-Joule-range energy pulses for producing the right energy pulses which could be of benefit for patients who suffer chronic headache, photophobia, and even nausea which could is sometimes triggered by a series of factors. The specific therapeutic effect known as acupunctural analgesia is the main objective of this medium-term project. It is a simple design on which commercially available software was employed for laser cavity design. Monte Carlo technique for skin light-transport, thermal diffusion and the possible thermal de-naturalization optical study and prediction will also be included in the presentation. Full optical characterization will be included and a complete set of recent results on the laser-skin interaction and the so called moxi-bustion from the laser design will be extensively described.

  20. Erbium hydride decomposition kinetics.

    Energy Technology Data Exchange (ETDEWEB)

    Ferrizz, Robert Matthew

    2006-11-01

    Thermal desorption spectroscopy (TDS) is used to study the decomposition kinetics of erbium hydride thin films. The TDS results presented in this report are analyzed quantitatively using Redhead's method to yield kinetic parameters (E{sub A} {approx} 54.2 kcal/mol), which are then utilized to predict hydrogen outgassing in vacuum for a variety of thermal treatments. Interestingly, it was found that the activation energy for desorption can vary by more than 7 kcal/mol (0.30 eV) for seemingly similar samples. In addition, small amounts of less-stable hydrogen were observed for all erbium dihydride films. A detailed explanation of several approaches for analyzing thermal desorption spectra to obtain kinetic information is included as an appendix.

  1. Interaction of water vapor with erbium and erbium dideuteride films

    International Nuclear Information System (INIS)

    Holloway, D.M.; Swartz, W.E. Jr.

    1976-01-01

    The reaction of water vapor with erbium and erbium dideuteride thin films was studied by x-ray diffraction, mass spectrometry and Auger electron spectroscopy. The data indicate that significant reactions take place above 573 K forming both the hydride and the oxide. The data also indicate that isotopic displacement occurs. These are important considerations in hydrogen storage applications

  2. An investigation of the thermoluminescence of Ge-doped SiO{sub 2} optical fibres for application in interface radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Abdul Rahman, A.T., E-mail: a.t.abdulrahman@surrey.ac.uk [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, GU2 7XH Guildford (United Kingdom); School of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA Malaysia (UiTM), Campus of Negeri Sembilan, 72000 Kuala Pilah (Malaysia); Hugtenburg, R.P. [Department of Medical Physics and Clinical Engineering, Abertawe Bro Morgannwg UHB and School of Medicine, Swansea University, Swansea SA2 8PP (United Kingdom); Abdul Sani, Siti Fairus; Alalawi, A.I.M. [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, GU2 7XH Guildford (United Kingdom); Issa, Fatma [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, GU2 7XH Guildford (United Kingdom); Department of Radiotherapy, Tripoli Medical Centre (TMC), Tripoli (Libya); Thomas, R. [Radiation Dosimetry Team, National Physical Laboratory, Teddington (United Kingdom); Barry, M.A. [Department of Medical Physics, The Royal Surrey County Hospital (RSCH) NHS Trust, Guildford, GU2 7XX Surrey (United Kingdom); Nisbet, A. [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, GU2 7XH Guildford (United Kingdom); Department of Medical Physics, The Royal Surrey County Hospital (RSCH) NHS Trust, Guildford, GU2 7XX Surrey (United Kingdom); Bradley, D.A. [Centre for Nuclear and Radiation Physics, Department of Physics, University of Surrey, GU2 7XH Guildford (United Kingdom); Department of Radiological Sciences, King Saud University, P.O. Box 10219, Riyadh 11432 (Saudi Arabia)

    2012-07-15

    We investigate the ability of high spatial resolution ({approx} 120 {mu}m) Ge-doped SiO{sub 2} TL dosimeters to measure photoelectron dose enhancement resulting from the use of a moderate to high-Z target (an iodinated contrast media) irradiated by 90 kVp X-rays. We imagine its application in a novel radiation synovectomy technique, modelled by a phantom containing a reservoir of I{sub 2} molecules at the interface of which the doped silica dosimeters are located. Measurements outside of the iodine photoelectron range are provided for using a stepped-design that allows insertion of the fibres within the phantom. Monte Carlo simulation (MCNPX) is used for verification. At the phantom medium I{sub 2}-interface additional photoelectron generation is observed, {approx}60% above that in the absence of the I{sub 2}, simulations providing agreement to within 3%. Percentage depth doses measured away from the iodine contrast medium reservoir are bounded by published PDDs at 80 kVp and 100 kVp. - Highlights: Black-Right-Pointing-Triangle Studies of dosimetric characteristic of commercially available doped silica optical fibres. Black-Right-Pointing-Triangle Investigation of the potential of the dosimeter in dose enhancement measurement. Black-Right-Pointing-Triangle Use of photoelectron dose enhancement as might be applied in radiation synovectomy. Black-Right-Pointing-Triangle Measurement of the percentage depth dose recorded by Ge-doped silica optical fibres. Black-Right-Pointing-Triangle The Monte Carlo simulation provides comparison against measured data.

  3. Obtaining, characterization and fibre use of nanostructured TiO_2 doped with tungsten as photocatalysts

    International Nuclear Information System (INIS)

    Soares, L.G.; Bergmann, C.P.; Alves, A.K.

    2016-01-01

    The use and applicability of nanomaterials are increasingly common in our day to day, due to propitiate more effective end products, lightweight and low cost. The nanomaterials used preferably in various applications is due to properties such as reduced particle size, diversified and high surface area. In this work nanostructured fibers of TiO_2 and TiO_2/WO_3 were obtained by electrospinning, annealed at temperatures between 650 deg C and 800 deg C, and its photocatalytic activity was evaluated. The technique of X-ray diffraction (XRD) was used to determine the crystalline structure and crystallite size. The morphology of nanomaterials was observed by scanning electron microscopy (SEM). Preliminary results indicate that the nano-doped tungsten presented more efficient in bleaching methyl orange dye, indicating a higher catalytic activity of this material compared to a standard catalyst. This phenomenon can be explained through the phases present and morphological characteristics of the fibers. (author)

  4. Magnetic Structure of Erbium

    DEFF Research Database (Denmark)

    Gibbs, D.; Bohr, Jakob; Axe, J. D.

    1986-01-01

    We present a synchrotron x-ray scattering study of the magnetic phases of erbium. In addition to the magnetic scattering located at the fundamental wave vector τm we also observe scattering from magnetoelastically induced charge modulations at the fundamental wave vector, at twice the fundamental......, and at positions split symmetrically about the fundamental. As the temperature is lowered below 52 K the charge and magnetic scattering display a sequence of lock-in transitions to rational wave vectors. A spin-slip description of the magnetic structure is presented which explains the wave vectors...

  5. Luminescent Solar Concentrators with Fibre Geometry

    NARCIS (Netherlands)

    Edelenbosch, O.Y.; Fisher, M.; Patrignani, L.; Sark, W.G.J.H.M. van; Chatten, A.J.

    2013-01-01

    The potential of a fibre luminescent solar concentrator has been explored by means of both analytical and ray-tracing techniques. Coated fibres have been found to be more efficient than homogeneously doped fibres, at low absorption. For practical fibres concentration is predicted to be linear

  6. Numerical analysis of Yb.sup.3+./sup. -sensitized Er.sup.3+./sup. -doped fibre-ring laser

    Czech Academy of Sciences Publication Activity Database

    Karásek, Miroslav; Kaňka, Jiří

    1998-01-01

    Roč. 145, č. 2 (1998), s. 133-137 ISSN 1350-2433 R&D Projects: GA AV ČR IAA267403 Keywords : optical fibre s * fibre lasers * numerical analysis * modelling * ring lasers Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.628, year: 1998

  7. Erbium environments in erbium-silicon/silica light emitting nanostructures

    International Nuclear Information System (INIS)

    Kashtiban, R J; Bangert, U; Crowe, I F; Halsall, M P

    2011-01-01

    Co-doping of SiO 2 with Si and Er to achieve silica fibre amplifiers has resulted in encouraging levels of light emission, much above those of Er-only doped SiO 2 . However, different fabrication methods, i.e., co-implantion and sequential implantation of Er and Si, has led to several factors difference in light levels. This paper looks into the reasons for these differences by establishing structure and local stoichiometry of the created entities via analytical transmission electron microscopy. In both cases Si-nanocrystals (NCs) have formed in the SiO 2 matrix. In the former case Er-ions are co-located with /integrated within the NCs, in the latter case NCs and Er are separate. By assessing the NCs' internal and interfacial structure with the surrounding material, we attempt to identify chemical/structural Er-phases/defects and their effect on the sensitising efficiency in the Er:Si-NCs system; high resolution phase contrast- and high angle dark field imaging as well as nano-scale spatially resolved electron energy core loss- and plasmon-spectroscopy carried out in an aberration corrected dedicated STEM lend valuable support to these studies.

  8. Effect of addition of erbium stabilized bismuth oxide on the conductivity of lanthanum doped ceria solid electrolyte for IT-SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Jaiswal, Nandini; Gupta, Brijesh; Kumar, Devendra; Parkash, Om, E-mail: oprakash.cer@itbhu.ac.in

    2015-06-05

    Highlights: • Bi{sub 0.8}Er{sub 0.2}O{sub 1.5} doped Ce{sub 0.85}La{sub 0.15}O{sub 1.925} system has been studied for the first time. • Composition 0.5ECLO has maximum conductivity. • Its conductivity is almost equal to that of SDC and GDC. • This makes 0.5ECLO is a potential candidate as a solid electrolyte for ITSOFCs. - Abstract: Nanosized powders of compositions, Bi{sub 0.8}Er{sub 0.2}O{sub 1.5} (ESB) and Ce{sub 0.85}La{sub 0.15}O{sub 1.925} (CLO) have been prepared using citrate–nitrate auto combustion method. ESB added CLO (ECLO) samples have been prepared by mixing nanosized CLO powder with 0.5, 1, 2 and 3 wt.% of ESB. X-ray diffraction patterns confirm that all the samples are single phase having cubic fluorite structure similar to CeO{sub 2}. Density of Ce{sub 0.85}La{sub 0.15}O{sub 1.925} increases with increasing ESB content. All the samples have been sintered at 1350 °C. All the ECLO samples have density more than 97% of the theoretical value. Field emission scanning electron microscope images show dense microstructure with distinct grains and grain boundaries. Impedance measurements have been made in the temperature range 200–700 °C in air. Addition of ESB increases the conductivity of the bulk as well as of grain boundaries. Ce{sub 0.85}La{sub 0.15}O{sub 1.925} with 0.5 wt.% of ESB exhibits the maximum conductivity 1.41 × 10{sup −2} S cm{sup −1} at 600 °C of all the compositions. This value is one order of magnitude higher than the conductivity of Ce{sub 0.85}La{sub 0.15}O{sub 1.925} (1.99 × 10{sup −3} S cm{sup −1})

  9. Practical Hydrogen Loading of Air Silica Fibres

    DEFF Research Database (Denmark)

    Sørensen, Henrik Rokkjær; Jensen, Jesper Bevensee; Jensen, Jesper Bo Damm

    2005-01-01

    A method for hydrogen-loading air-silica optical fibres has been developed allowing out-diffusion times comparable to standard step-index fibres. Examples of the first grating written in Ge-doped air-silica fibres using a 266nm UV-laser are shown.......A method for hydrogen-loading air-silica optical fibres has been developed allowing out-diffusion times comparable to standard step-index fibres. Examples of the first grating written in Ge-doped air-silica fibres using a 266nm UV-laser are shown....

  10. Status of fiber lasers study of on ytterbium doped fiber laser and laser spectroscopy of doped fibers; Etat de l`art des lasers a fibre, etude d`un laser a fibre dopee ytterbium et spectroscopie laser de fibres dopees

    Energy Technology Data Exchange (ETDEWEB)

    Magne, S

    1994-07-01

    This work shows all the advantages and drawbacks of the rare-earth-doped fiber lasers and fiber optical amplifiers, pointing out their potential use for instrumentation and optical fiber sensor technology. The theory of light propagation in optical fibers is presented in order to understand the manufacturing methods. A comparative study of preform surface and concentration analysis is performed. The gain behaviour is also thoroughly examined. A synthesis of all technological parameters of the fiber laser is then established and all technologies of the constituting integrated components are reviewed and compared. The experimental techniques mainly involve: site selective excitation tunability, cooperative luminescence, oxidation state changes induced by gamma irradiation, ytterbium-doped mono-mode continuous wave tunable three-level fiber laser. (TEC). 622 refs., 176 figs.

  11. Erbium diffusion in titanium dioxide

    Directory of Open Access Journals (Sweden)

    Louise Basse

    2017-04-01

    Full Text Available The diffusivity of erbium in the anatase phase of titanium dioxide (TiO2 has been studied for various temperatures ranging from 800 °C to 1, 000 °C. Samples of TiO2, with a 10 nm thick buried layer containing 0.5 at% erbium, were fabricated by radio-frequency magnetron sputtering and subsequently heat treated. The erbium concentration profiles were measured by secondary ion mass spectrometry, allowing for determination of the temperature-dependent diffusion coefficients. These were found to follow an Arrhenius law with an activation energy of ( 2.1 ± 0.2 eV. X-ray diffraction revealed that the TiO2 films consisted of polycrystalline grains of size ≈ 100 nm.

  12. The route toward a diode-pumped 1-W erbium 3-µm fiber laser

    NARCIS (Netherlands)

    Pollnau, Markus

    1997-01-01

    A rate-equation analysis of the erbium 3-um ZBLAN fiber laser is performed. The computer calculation includes the longitudinal spatial resolution of the host material. It considers ground-state bleaching, excited-state absorption (ESA), interionic processes, lifetime quenching by co-doping, and

  13. Modelling the competition between photo-darkening and photo-bleaching effects in high-power ytterbium-doped fibre amplifiers

    Science.gov (United States)

    Jolly, A.; Vinçont, C.; Pierre, Ch.; Boullet, J.

    2017-08-01

    We propose an innovative, fully space-time model to take into account the seed-dependent nature of ageing penalties in high-power ytterbium-doped fibre amplifiers. Ageing is shown to be based on the on-going competition between photo-darkening and photo-bleaching phenomena. Our approach is based on the natural interplay between the excited states of co-existing ytterbium pairs and colour centres in highly doped fibres, in the presence of thermal coupling between the closely spaced excited states. As initiated from IR photons, the excitation of colour centres up to the UV band is supposed to be governed by multi-photon absorption. The interactions of interest in the kinetics of photo-bleaching then take the form of highly efficient charge transfers, which imply the reduction of some fraction of the basically trivalent ions to their divalent state. Due to the activation of ytterbium pairs by means of energy transfer up-conversion, these interactions get more and more effective at elevated operating powers. Computational results using these principles actually help to fit our experimental data regarding seeding effects, as well as fully generic trends already evidenced in the literature. This gives a fine demonstration for the need to discriminate co-active pump and signal contributions. Our self-consistent, still simplified model then consists of a valuable tool to help for a deeper understanding of the ageing issues. Furthermore, considering higher-order ytterbium aggregates, this should open new routes towards more comprehensive models.

  14. OPTICAL FIBRES AND FIBREOPTIC SENSORS: Fibreoptic distributed temperature sensor with spectral filtration by directional fibre couplers

    Science.gov (United States)

    Kuznetsov, A. G.; Babin, Sergei A.; Shelemba, Ivan S.

    2009-11-01

    We demonstrate a Raman-based all-fibre temperature sensor utilising a pulsed erbium fibre laser. The sensor is made of a standard single-mode telecom fibre, SMF-28, and includes a number of directional couplers as band-pass filters. The temperature profile along a 7-km fibreoptic line is measured with an accuracy of 2oC and a spatial resolution of 10 m. In data processing, we take into account the difference in attenuation between the spectral components of the backscatter signal.

  15. A microring multimode laser using hollow polymer optical fibre

    Indian Academy of Sciences (India)

    Dye-doped optical fibre; fibre laser; microcavity; whispering gallery mode. ... Cylindrical microcavities with diameters 155, 340 and 615 m were fabricated from a dye-doped hollow polymer optical fibre preform. ... International School of Photonics, Cochin University of Science and Technology, Kochi 682 022, India ...

  16. Annealing behaviour of MeV erbium implanted lithium niobate

    Energy Technology Data Exchange (ETDEWEB)

    Gortmaker, P; McCallum, J C [Royal Melbourne Inst. of Tech., VIC (Australia)

    1994-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  17. Annealing behaviour of MeV erbium implanted lithium niobate

    Energy Technology Data Exchange (ETDEWEB)

    Gortmaker, P.; McCallum, J.C. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  18. Dipolar quantum gases of erbium

    International Nuclear Information System (INIS)

    Frisch, A.

    2014-01-01

    Since the preparation of the first Bose-Einstein condensate about two decades ago and the first degenerate Fermi gas following four years later a plethora of fascinating quantum phenomena have been explored. The vast majority of experiments focused on quantum degenerate atomic gases with short-range contact interaction between particles. Atomic species with large magnetic dipole moments, such as chromium, dysprosium, and erbium, offer unique possibilities to investigate phenomena arising from dipolar interaction. This kind of interaction is not only long-range but also anisotropic in character and imprints qualitatively novel features on the system. Prominent examples are the d-wave collapse of a dipolar Bose-Einstein condensate of chromium atoms realized by the group in Stuttgart, the spin magnetization and demagnetization dynamics observed by groups in Stuttgart, Paris, and Stanford, and the deformation of the Fermi surface observed by our group in Innsbruck. This thesis reports on the creation and study of the first Bose-Einstein condensate and degenerate Fermi gas of erbium atoms. Erbium belongs to the lanthanide group of elements and has a large magnetic moment of seven Bohr magneton. In particular, this thesis describes the experimental apparatus and the sequence for producing a dipolar quantum gas. There is an emphasis on the production of the narrow-line magneto-optical trap of erbium since this represents a very efficient and robust laser-cooling scheme that greatly simplifies the experimental procedure. After describing the experimental setup this thesis focuses on several fundamental questions related to the dipolar character of erbium and to its lanthanide nature. A first set of studies centers on the scattering properties of ultracold erbium atoms, including the elastic and the inelastic cross section and the spectrum of Feshbach resonances. Specifically, we observe that identical dipolar fermions do collide and rethermalize even at low temperatures

  19. Near-infrared and upconversion properties of neodymium-doped RE0.8La0.2VO4 (RE = Y, Gd) single-crystal fibres grown by the laser-heated pedestal growth technique

    International Nuclear Information System (INIS)

    Camargo, A S S de; Nunes, L A O; Andreeta, M R B; Hernandes, A C

    2002-01-01

    Neodymium-doped Y 0.8 La 0.2 VO 4 and Gd 0.8 La 0.2 VO 4 single-crystal fibres were successfully grown by the laser-heated pedestal growth (LHPG) technique. The fibres were completely transparent and no dark inclusions were observed by optical microscopy. In the characterization process, microprobe Raman, optical absorption, fluorescence, lifetime, and gain-excited state absorption spectra were investigated in addition to upconversion measurements. The fibres' structural and spectroscopic properties are very similar to those of YVO 4 and GdVO 4 bulk laser crystals, with the advantageous characteristic of broadened spectral linewidths that facilitate the pumping of the 1064 nm emission by a diode laser. These fairly new crystal compositions, that can be grown in fast and economical processes, are potential candidates for use as compact laser-active media

  20. Absorption and luminescence characteristics of {sup 5}I{sub 7} ↔ {sup 5}I{sub 8} transitions of the holmium ion in Ho{sup 3+}-doped aluminosilicate preforms and fibres

    Energy Technology Data Exchange (ETDEWEB)

    Ryabochkina, P A; Chabushkin, A N [N.P. Ogarev Mordovian State University, Saransk (Russian Federation); Kosolapov, A F [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Kurkov, A S [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-02-28

    We have obtained the spectral dependences of the absorption cross sections for the Ho{sup 3+} {sup 5}I{sub 8} → {sup 5}I{sub 6} and {sup 5}I{sub 8} → {sup 5}I{sub 7} transitions in Ho{sup 3+}-doped aluminosilicate fibres and the spectral dependence of the stimulated emission cross section for the Ho{sup 3+} {sup 5}I{sub 7} → {sup 5}I{sub 8} laser transition in Ho{sup 3+}-doped aluminosilicate fibre preforms. The lifetime of the Ho{sup 3+} {sup 5}I{sub 7} upper laser level in the preforms has been determined. (lasers)

  1. Effect of Erbium Nanoparticles on Optical Properties of Zinc Borotellurite Glass System

    Directory of Open Access Journals (Sweden)

    Azlan Muhammad Noorazlan

    2013-01-01

    Full Text Available Erbium nanoparticles (NPs doped zinc borotellurite glasses have been prepared by conventional melt-quenching technique with the chemical composition {[(TeO20.70(B2O30.30]1-x(ZnOx}1-y(Er3O2y (where y=0.005,0.01,0.02,0.03,0.04,0.05. The structural properties of the prepared glasses were determined via X-ray diffraction (XRD analysis and FTIR analysis. It was confirmed that the prepared glasses are amorphous. The bonding parameters of the glasses were analyzed by using FTIR analysis and were confirmed to be ionic in nature. The refractive index increases as the content of erbium NPs increases. The optical absorption spectra revealed that fundamental absorption edge shifts to longer wavelength as the content of erbium NPs increases. The value of band gap had been calculated and shown to be decreased with an increase content of erbium NPs. The Urbach energy was shown to be linearly increased with an increase content of erbium NPs oxides.

  2. Erbium concentration dependent absorbance in tellurite glass

    Energy Technology Data Exchange (ETDEWEB)

    Sazali, E. S., E-mail: mdsupar@utm; Rohani, M. S., E-mail: mdsupar@utm; Sahar, M. R., E-mail: mdsupar@utm; Arifin, R., E-mail: mdsupar@utm; Ghoshal, S. K., E-mail: mdsupar@utm; Hamzah, K., E-mail: mdsupar@utm [Advanced Optical Material Research Group, Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor Bahru, Johor (Malaysia)

    2014-09-25

    Enhancing the optical absorption cross-section in topically important rare earth doped tellurite glasses is challenging for photonic devices. Controlled synthesis and detailed characterizations of the optical properties of these glasses are important for the optimization. The influence of varying concentration of Er{sup 3+} ions on the absorbance characteristics of lead tellurite glasses synthesized via melt-quenching technique are investigated. The UV-Vis absorption spectra exhibits six prominent peaks centered at 490, 526, 652, 800, 982 and 1520 nm ascribed to the transitions in erbium ion from the ground state to the excited states {sup 4}F{sub 7/2}, {sup 2}H{sub 11/2}, {sup 4}F{sub 9/2}, {sup 4}I{sub 9/2}, {sup 2}H{sub 11/2} and {sup 4}I{sub 13/2}, respectively. The results are analyzed by means of optical band gap E{sub g} and Urbach energy E{sub u}. The values of the energy band gap are found decreased from 2.82 to 2.51 eV and the Urbach energy increased from 0.15 to 0.24 eV with the increase of the Er{sub 2}O{sub 3} concentration from 0 to 1.5 mol%. The excellent absorbance of the prepared tellurite glasses makes them suitable for fabricating solid state lasers.

  3. Preparation of Erbium-169 (169Er) Using Natural Erbium Target

    International Nuclear Information System (INIS)

    Azmairit Aziz; Nana Suherman

    2009-01-01

    The therapeutic radiopharmaceuticals which is labelled by β-particle emission are now increasingly used in nuclear medicine. Erbium-169 ('1 69 Er) is one of radioisotopes that can be used for radiation synovectomy (radio synovectomy) in the treatment of inflammatory joint diseases (arthritis) due to its β- particle emission (T 1/2 =9.4 days, E β maximum =0.34 MeV). The preliminary study on preparation of 169 Er by using natural erbium oxide (Er 2 O 3 ) target irradiated at TRIGA 2000 Bandung reactor has been carried out. The irradiated target was dissolved in hydrochloric acid solution and gentle warming. The optimum condition of 169 Er preparation was obtained by dissolution of 169 Er 2 O 3 by using 1N HCl solution. The radiochemical purity of 169 ErCl 3 was determined by paper chromatography, thin layer chromatography and paper electrophoresis techniques. The solution of 169 ErCl 3 formed was obtained with the pH of 1.5 – 2, clear, with the specific activity of 0.48 – 0.71 MBq/mg Er. The solution has the radiochemical purity of 98.32 ± 1.28% and the radionuclide purity of 99.98%. Study on the stability of 169 ErCl 3 solution showed that the solution was still stable for 4 days at room temperature with the radiochemical purity more than 95%. (author)

  4. Systems of erbium chloride- carbamide- water and erbium nitrate- carbamide- water at 30 deg C

    International Nuclear Information System (INIS)

    Ajtimbetov, K.; Sulajmankulov, K.S.; Batyuk, A.G.; Ismailov, M.

    1975-01-01

    The systems erbium chloride - carbamide - water and erbium nitrate - carbamide - water were studied by solubility method at 30 deg C. In the system erbium chloride - carbamide - water three compounds were detected: ErClsub(3).6CO(NHsub(2))sub(2), ErClsub(3).4CO(NHsub(2))sub(2), ErClsub(3).2CO(NHsub(2))sub2.6Hsub(2)O. In the system erbium nitrate -carbamide - water two new compounds were found: Er(NOsub(3))sub(3).4CO(NHsub(2))sub2, Er(NOsub(3) )sub(3)

  5. Room-temperature electroluminescence of Er-doped hydrogenated amorphous silicon

    Energy Technology Data Exchange (ETDEWEB)

    Gusev, Oleg; Bresler, Mikhail; Kuznetsov, Alexey; Kudoyarova, Vera; Pak, Petr; Terukov, Evgenii; Tsendin, Konstantin; Yassievich, Irina [A F Ioffe Physico-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation); Fuhs, Walther [Hahn-Meitner Institut, Abteilung Photovoltaik, Rudower Chaussee 5, D-12489 Berlin (Germany); Weiser, Gerhard [Phillips-Universitat Marburg, Fachbereich Physik, D-35032 Marburg (Germany)

    1998-05-11

    We have observed room-temperature erbium-ion electroluminescence in erbium-doped amorphous silicon. Electrical conduction through the structure is controlled by thermally activated ionization of deep D{sup -} defects in an electric field and the reverse process of capture of mobile electrons by D{sup 0} states. Defect-related Auger excitation (DRAE) is responsible for excitation of erbium ions located close to dangling-bond defects. Our experimental data are consistent with the mechanisms proposed

  6. Fibre tracking

    International Nuclear Information System (INIS)

    Gaillard, J.M.

    1994-03-01

    A large-size scintillating plastic fibre tracking detector was built as part of the upgrade of the UA2 central detector at the SPS proton-antiproton collider. The cylindrical fibre detector of average radius of 40 cm consisted of 60000 plastic fibres with an active length of 2.1 m. One of the main motivations was to improve the electron identification. The fibre ends were bunched to be coupled to read-out systems of image intensifier plus CCD, 32 in total. The quality and the reliability of the UA2 fibre detector performance exceeded expectations throughout its years of operation. A few examples of the use of image intensifiers and of scintillating fibres in biological instrumentation are described. (R.P.) 11 refs., 15 figs., 2 tabs

  7. Modification of erbium photoluminescence excitation spectra for the emission wavelength 1.54 μm in mesoscopic structures

    International Nuclear Information System (INIS)

    Gaponenko, N.V.; Unuchak, D.M.; Mudryi, A.V.; Malyarevich, G.K.; Gusev, O.B.; Stepikhova, M.V.; Krasilnikova, L.V.; Stupak, A.P.; Kleshcheva, S.M.; Samoilovich, M.I.; Tsvetkov, M.Yu.

    2006-01-01

    Photoluminescence excitation (PLE) spectra for the emission wavelength 1.54 μm were studied for erbium-doped xerogels embedded in artificial opals and porous anodic alumina films. Opals were chosen with photonic stop-band in green spectral range, where excitation of 1.54 μm occurs most efficiently. In comparison to the structure erbium-doped titania xerogel/porous anodic alumina/silicon the photoluminescence excitation spectra for 1.54 μm emission wavelength significantly changes for the same xerogels embedded in artificial opals. Enhancement of erbium-related 1.54 μm emission was observed from the structure Fe 2 O 3 xerogel/porous anodic alumina fabricated on silicon, having some incompletely anodized aluminium, under excitation with either the lasing source at 532 nm or xenon lamp. Evident difference in PLE spectra for erbium doped TiO 2 and Fe 2 O 3 xerogels in porous anodic alumina is observed

  8. Analysis of gain and noise performance of bidirecttionally pumped Pr.sup.3+./sup. -doped fluoride fibre amplifier configurations with umbalanced pumping

    Czech Academy of Sciences Publication Activity Database

    Vallés, J. A.; Lázaro, J. A.; Hotoleanu, M.; Karásek, Miroslav; Voiculescu, E.

    1998-01-01

    Roč. 45, č. 12 (1998), s. 2551-2560 ISSN 0950-0340 Grant - others:EU COST(XE) OC 241.10 Keywords : optical fibre s * fibre lasers * amplifiers Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.165, year: 1998

  9. Liquid filling of photonic crystal fibres for grating writing

    DEFF Research Database (Denmark)

    Sørensen, Henrik Rokkjær; Canning, John; Lægsgaard, Jesper

    2007-01-01

    liquid filling of photonic crystal fibres reduces the scattering from air–glass interfaces during Bragg grating writing in many layered photonic crystal fibres. Within experimental uncertainty, the grating index modulation of a grating written in germanium-doped photonic crystal fibre with 10 rings...

  10. Nanoscale nonlinear effects in Erbium-implanted Yttrium Orthosilicate

    Energy Technology Data Exchange (ETDEWEB)

    Kukharchyk, Nadezhda, E-mail: nadezhda.kukharchyk@physik.uni-saarland.de [Experimentalphysik, Universität des Saarlandes, D-66123 Saarbrücken (Germany); Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Shvarkov, Stepan [Optoelektronische Materialien und Bauelemente, Universität Paderborn, D-33098 Padeborn (Germany); Probst, Sebastian [Quantronics group, Service de Physique de l' Etat Condense, DSM/IRAMIS/SPEC, CNRS UMR 3680, CEA-Saclay, 91191 Gif-sur-Yvette cedex (France); Xia, Kangwei [3. Physikalisches Institut, Universität Stuttgart, D-70569 Stuttgart (Germany); Becker, Hans-Werner [RUBION, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Pal, Shovon [Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); AG THz Spectroscopie und Technologie, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Markmann, Sergej [AG THz Spectroscopie und Technologie, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Kolesov, Roman; Siyushev, Petr; Wrachtrup, Jörg [3. Physikalisches Institut, Universität Stuttgart, D-70569 Stuttgart (Germany); Ludwig, Arne [Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Ustinov, Alexey V. [Physikalisches Institut, Karlsruhe Institute of Technology, D-76128 Karlsruhe (Germany); Wieck, Andreas D. [Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); and others

    2016-09-15

    Doping of substrates at desired locations is a key technology for spin-based quantum memory devices. Focused ion beam implantation is well-suited for this task due to its high spacial resolution. In this work, we investigate ion-beam implanted Erbium ensembles in Yttrium Orthosilicate crystals by means of confocal photoluminescence spectroscopy. The sample temperature and the post-implantation annealing step strongly reverberate in the properties of the implanted ions. We find that hot implantation leads to a higher activation rate of the ions. At high enough fluences, the relation between the fluence and final concentration of ions becomes non-linear. Two models are developed explaining the observed behavior.

  11. Perioral Rejuvenation With Ablative Erbium Resurfacing.

    Science.gov (United States)

    Cohen, Joel L

    2015-11-01

    Since the introduction of the scanning full-field erbium laser, misconceptions regarding ablative erbium resurfacing have resulted in its being largely overshadowed by ablative fractional resurfacing. This case report illustrates the appropriateness of full-field erbium ablation for perioral resurfacing. A patient with profoundly severe perioral photodamage etched-in lines underwent full-field ablative perioral resurfacing with an erbium laser (Contour TRL, Sciton Inc., Palo Alto, CA) that allows separate control of ablation and coagulation. The pre-procedure consultations included evaluation of the severity of etched-in lines, and discussion of patient goals, expectations, and appropriate treatment options, as well as a review of patient photos and post-treatment care required. The author generally avoids full-field erbium ablation in patients with Fitzpatrick type IV and above. For each of 2 treatment sessions (separated by approximately 4 months), the patient received (12 cc plain 2% lidodaine) sulcus blocks before undergoing 4 passes with the erbium laser at 150 μ ablation, no coagulation, and then some very focal 30 μ ablation to areas of residual lines still visualized through the pinpoint bleeding. Similarly, full-field ablative resurfacing can be very reliable for significant wrinkles and creping in the lower eyelid skin--where often a single treatment of 80 μ ablation, 50 μ coagulation can lead to a nice improvement. Standardized digital imaging revealed significant improvement in deeply etched rhytides without significant adverse events. For appropriately selected patients requiring perioral (or periorbital) rejuvenation, full-field ablative erbium resurfacing is safe, efficacious and merits consideration.

  12. Synthesis, structural modelling and luminescence of a novel erbium(III) complex with 2,4-nonanedione and 2,2‧-bipyridine ligands for chitosan matrices doping

    Science.gov (United States)

    Martín-Ramos, P.; Chamorro-Posada, P.; Ramos Silva, M.; Pereira da Silva, P. S.; Martín, I. R.; Lahoz, F.; Lavín, V.; Martín-Gil, J.

    2015-03-01

    We report the synthesis, the Sparkle/PM7 semi-empirical quantum model for the ground state geometry and the absorption/luminescent properties of the Er3+ ternary complex [Er(nd)3(bipy)] (where Hnd is 2,4-nonanedione and bipy is 2,2‧-bipyridine). The solid-state electronic absorption spectra and the photoluminescent spectra show long-wavelength 4f-4f transitions which provide a potential use of the compound as a NIR-emitting material for the doping of polymer-based matrices for waveguides or for bio-analytical applications. The dispersion of the novel complex in a biocompatible chitosan film has been assessed.

  13. Erbium-doped borosilicate glasses containing various amounts of P2O5 and Al2O3: Influence of the silica content on the structure and thermal, physical, optical and luminescence properties

    International Nuclear Information System (INIS)

    Bourhis, Kevin; Massera, Jonathan; Petit, Laeticia; Koponen, Joona; Fargues, Alexandre; Cardinal, Thierry; Hupa, Leena; Hupa, Mikko; Dussauze, Marc; Rodriguez, Vincent; Ferraris, Monica

    2015-01-01

    Highlights: • Er 3+ doped borosilicate glasses were processed with different compositions and characterizations. • An increase in the SiO 2 content leads to a silicate-rich environment around the Er 3+ site. • An increase in the SiO 2 content decreases the Er 3+ absorption cross-section at 980 nm. • Glasses with 60 mol% of SiO 2 exhibit a stronger emission intensity at 1530 nm than glasses with x = 50. • Highest 1.5 μm emission intensity was achieved for the Al and P containing glass with 60 mol% of SiO 2 . - Abstract: The influence of the silica content on several properties of Er-doped borosilicate glasses in the presence of various amounts of P 2 O 5 and Al 2 O 3 has been investigated. The introduction of P 2 O 5 and/or Al 2 O 3 are responsible for structural modifications in the glass network through a charge-compensation mechanism related to the formation of negatively-charged PO 4 and AlO 4 groups or through the formation of AlPO 4 -like structural units. In this paper, we show that an increase in the SiO 2 content leads to a silicate-rich environment around the Er 3+ site, resulting in an increased dependence of the Er 3+ ions optical and luminescence properties on the P 2 O 5 and/or Al 2 O 3 concentration. The highest emission intensity at 1.5 μm was achieved for the glass with an equal proportion of P and Al in the glass system with 60 mol% of SiO 2

  14. Magnetic structures of erbium under high pressure

    DEFF Research Database (Denmark)

    Kawano, S.; Lebech, B.; Achiwa, N.

    1993-01-01

    Neutron diffraction studies of the magnetic structures of erbium metal at 4.5 K and 11.5 kbar hydrostatic pressure have revealed that the transition to a conical structure at low temperatures is suppressed and that the cycloidal structure, with modulation vector Q congruent-to (2/7 2pi/c)c persists...

  15. Double cascade erbium fiber laser at 1.7 µm, 2.7 µm, and 1.6 µm

    NARCIS (Netherlands)

    Schneider, J.; Frerichs, Ch.; Carbonnier, C.; Unrau, U.B.; Pollnau, Markus; Lüthy, W.; Weber, H.P.

    The output power of the erbium laser at 2.7 um (4I11/2 -> 4I13/2) is enhanced due to simultaneous laser action at 1.7 um (4S3/2 -> 4I9/2) and 1.6 um (4I13/2 -> 4I15/2) in an Er3+-doped fluorozirconate fiber. The laser cascade overwhelms the saturation effect for the transition at 2.7 um by

  16. Multi-operational tuneable Q-switched mode-locking Er fibre laser

    Science.gov (United States)

    Qamar, F. Z.

    2018-01-01

    A wavelength-spacing tuneable, Q-switched mode-locking (QML) erbium-doped fibre laser based on non-linear polarization rotation controlled by four waveplates and a cube polarizer is proposed. A mode-locked pulse train using two quarter-wave plates and a half-wave plate (HWP) is obtained first, and then an extra HWP is inserted into the cavity to produce different operation regimes. The evolutions of temporal and spectral dynamics with different orientation angles of the extra HWP are investigated. A fully modulated stable QML pulse train is observed experimentally. This is, to the author’s best knowledge, the first experimental work reporting QML operation without adding an extra saturable absorber inside the laser cavity. Multi-wavelength pulse laser operation, multi-pulse train continuous-wave mode-locking operation and pulse-splitting operations are also reported at certain HWP angles. The observed operational dynamics are interpreted as a mutual interaction of dispersion, non-linear effect and insertion loss. This work provides a new mechanism for fabricating cheap tuneable multi-wavelength lasers with QML pulses.

  17. Simultaneous determination of dysprosium, holmium and erbium in high purity rare earth oxides by second order derivative spectrophotometry

    International Nuclear Information System (INIS)

    Anbu, M.; Prasada Rao, T.; Iyer, C. S. P.; Damodaran, A. D.

    1996-01-01

    High purity individual rare earth oxides are increasingly used as major components in lasers (Y 2 O 3 ), phosphors (YVO 3 , Eu 2 O 3 ), magnetic bubble memory films (Gd 2 O 3 ) and refractive-index lenses and fibre optics (La 2 O 3 ). The determination of individual lanthanides in high purity rare earth oxides is a more important and difficult task. This paper reports the utilization of higher order derivative spectrophotometry for the simultaneous determination of dysprosium, holmium and erbium in high purity rare earth oxides. The developed procedure is simple, reliable and allows the determination of 0.001 to 0.2% of dysprosium, holmium and erbium in several rare earth. (author). 9 refs, 2 figs, 2 tabs

  18. Influence of P2O5 and Al2O3 content on the structure of erbium-doped borosilicate glasses and on their physical, thermal, optical and luminescence properties

    International Nuclear Information System (INIS)

    Bourhis, Kevin; Massera, Jonathan; Petit, Laeticia; Ihalainen, Heikki; Fargues, Alexandre; Cardinal, Thierry; Hupa, Leena; Hupa, Mikko; Dussauze, Marc; Rodriguez, Vincent; Boussard-Plédel, Catherine; Bureau, Bruno; Roiland, Claire; Ferraris, Monica

    2015-01-01

    Highlights: • Reorganization of the glass structure induced by the addition of P 2 O 5 or Al 2 O 3 . • Emission properties related to the presence of P or Al in the Er 3+ coordination shell. • Declustering observed upon addition of P 2 O 5 . • No declustering upon addition of Al 2 O 3 . - Abstract: The effect of P 2 O 5 and/or Al 2 O 3 addition in Er-doped borosilicate glasses on the physical, thermal, optical, and luminescence properties is investigated. The changes in these glass properties are related to the glass structure modifications induced by the addition of P 2 O 5 and/or Al 2 O 3 , which were probed by FTIR, 11 B MAS NMR and X-ray photoelectron spectroscopies. Variations of the polymerization degree of the silicate tetrahedra and modifications in the [3] B/ [4] B ratio are explained by a charge compensation mechanism due to the formation of AlO 4 , PO 4 groups and the formation of Al-O-P linkages in the glass network. From the absorption and luminescence properties of the Er 3+ ions at 980 nm and 1530 nm, declustering is suspected for the highest P 2 O 5 concentrations while for the highest Al 2 O 3 concentrations no declustering is observed

  19. Gain flattened L-band EDFA based on upgraded C-band EDFA using forward ASE pumping in an EDF section

    DEFF Research Database (Denmark)

    Buxens Azcoaga, Alvaro Juan; Poulsen, Henrik Nørskov; Clausen, Anders

    2000-01-01

    A novel method is presented for implementing an L-band erbium doped fibre amplifier (EDFA) making use of forward amplified spontaneous emission pumping, from a commercially available c-band EDFA, in an erbium doped fibre. Tuning of the length of erbium doped fibre enables a flat gain characteristic...... to be obtained with a low noise figure over the entire L-band window....

  20. Influence of P{sub 2}O{sub 5} and Al{sub 2}O{sub 3} content on the structure of erbium-doped borosilicate glasses and on their physical, thermal, optical and luminescence properties

    Energy Technology Data Exchange (ETDEWEB)

    Bourhis, Kevin, E-mail: k.bourhis@argolight.com [Politecnico di Torino, DISAT, Istituto di Ingegneria e Fisica dei Materiali, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Massera, Jonathan [Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); Petit, Laeticia; Ihalainen, Heikki [nLIGHT Corporation, Sorronrinne 9, FI-08500 Lohja (Finland); Fargues, Alexandre; Cardinal, Thierry [CNRS, Université de Bordeaux, ISM, 351Cours de la Libération, F-33405 Talence (France); Hupa, Leena; Hupa, Mikko [Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); Dussauze, Marc; Rodriguez, Vincent [CNRS, Université de Bordeaux, ICMCB, 87 Avenue du Dr Schweitzer, F-33608 Pessac (France); Boussard-Plédel, Catherine; Bureau, Bruno; Roiland, Claire [Equipe Verres et Céramiques, UMR-CNRS 6226, Inst. des Sciences chimiques de Rennes, Université de Rennes 1, 35042 Rennes CEDEX (France); Ferraris, Monica [Politecnico di Torino, DISAT, Istituto di Ingegneria e Fisica dei Materiali, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy)

    2015-03-15

    Highlights: • Reorganization of the glass structure induced by the addition of P{sub 2}O{sub 5} or Al{sub 2}O{sub 3}. • Emission properties related to the presence of P or Al in the Er{sup 3+} coordination shell. • Declustering observed upon addition of P{sub 2}O{sub 5}. • No declustering upon addition of Al{sub 2}O{sub 3}. - Abstract: The effect of P{sub 2}O{sub 5} and/or Al{sub 2}O{sub 3} addition in Er-doped borosilicate glasses on the physical, thermal, optical, and luminescence properties is investigated. The changes in these glass properties are related to the glass structure modifications induced by the addition of P{sub 2}O{sub 5} and/or Al{sub 2}O{sub 3}, which were probed by FTIR, {sup 11}B MAS NMR and X-ray photoelectron spectroscopies. Variations of the polymerization degree of the silicate tetrahedra and modifications in the {sup [3]}B/{sup [4]}B ratio are explained by a charge compensation mechanism due to the formation of AlO{sub 4}, PO{sub 4} groups and the formation of Al-O-P linkages in the glass network. From the absorption and luminescence properties of the Er{sup 3+} ions at 980 nm and 1530 nm, declustering is suspected for the highest P{sub 2}O{sub 5} concentrations while for the highest Al{sub 2}O{sub 3} concentrations no declustering is observed.

  1. The renaissance and bright future of fibre lasers

    International Nuclear Information System (INIS)

    Tuennermann, A; Schreiber, T; Roeser, F; Liem, A; Hoefer, S; Zellmer, H; Nolte, S; Limpert, J

    2005-01-01

    The first rare-earth-doped fibre lasers were operated in the early 1960s and produced a few milliwatts at a wavelength around 1 μm. For the next several decades, fibre lasers were little more than a low-power laboratory curiosity. Recently, however, fibre lasers have entered the realm of kilowatt powers with diffraction-limited beam quality. In this paper we review the reasons for this power evolution. Beyond this, we will discuss how the next generation of fibres, so-called photonic crystal fibres, enable upward power scaling and therefore open up the avenue to new performance levels of solid-state lasers

  2. Utilizing wheel-ring architecture for stable and selectable single-longitudinal-mode erbium fiber laser

    Science.gov (United States)

    Yeh, Chien-Hung; Yang, Zi-Qing; Huang, Tzu-Jung; Chow, Chi-Wai

    2018-03-01

    To achieve a steady single-longitudinal-mode (SLM) erbium-doped fiber (EDF) laser, the wheel-ring architecture is proposed in the laser cavity. According to Vernier effect, the proposed wheel-ring can produce three different free spectrum ranges (FSRs) to serve as the mode-filter for suppressing the densely multi-longitudinal-mode (MLM). Here, to complete wavelength-tunable EDF laser, an optical tunable bandpass filter (OTBF) is utilized inside the cavity for tuning arbitrarily. In addition, the entire output performances of the proposed EDF wheel-ring laser are also discussed and analyzed experimentally.

  3. A model to obtain an optimum erbium desity for gain increasing in EDFA

    OpenAIRE

    E. Arzi; A. Hassani; F. E. Seraji

    2003-01-01

      In this paper, we suggest a novel model, based on input pump power and wave guidestructure, to calculate the Er-density profile in Erbium doped fiber amplifiers. This optimization is carried out for both SMF and DSF fibers. These optimized profiles have a Gaussian-like shape. Using the SMF optimized Er-density profile, high gain enhancement is obtained in a relatively short length of fibers. On the other hand, the DSF optimized profile shows small changes in the gain, which agrees with the ...

  4. A model to obtain an optimum erbium desity for gain increasing in EDFA

    Directory of Open Access Journals (Sweden)

    E. Arzi

    2003-12-01

    Full Text Available   In this paper, we suggest a novel model, based on input pump power and wave guidestructure, to calculate the Er-density profile in Erbium doped fiber amplifiers. This optimization is carried out for both SMF and DSF fibers. These optimized profiles have a Gaussian-like shape. Using the SMF optimized Er-density profile, high gain enhancement is obtained in a relatively short length of fibers. On the other hand, the DSF optimized profile shows small changes in the gain, which agrees with the previously report on other method of gain enhancement. This model is applicable to all active waveguides and any other dopant as well .

  5. fibre separator

    African Journals Online (AJOL)

    ISHIOMA

    sharp edged spiral worm and four fixed blades, a pair of adjustable blades, ... energy and/or for the production of other products. ... 388 Afr. J. Environ. Sci. Technol. Figure 1. Layers of the palm fruit. planting. ... a skeleton of hard fibre running lengthwise through the ... maximum temperature of 28 - 32°C which is peculiar to.

  6. The growth of crystals of erbium hydride

    International Nuclear Information System (INIS)

    Grimshaw, J.A.; Spooner, F.J.; Wilson, C.G.; McQuillan, A.D.

    1981-01-01

    Crystals of the rare-earth hydride ErH 2 have been produced with face areas greater than a square millimetre and corresponding volumes exceeding those of earlier crystals by orders of magnitude. The hydride, which was produced in bulk polycrystalline form by hydriding erbium metal at 950 0 C, has been examined by optical and X-ray techniques. For material of composition ErH 2 and ErHsub(1.8) the size of the grains and their degree of strain appears to depend more on oxygen contamination during formation and on the subsequent cooling procedure, than on the size of erbium metal crystals in the starting material. (author)

  7. Scintillating fibres

    International Nuclear Information System (INIS)

    Nahnhauer, R.

    1990-01-01

    In the search for new detector techniques, scintillating fibre technology has already gained a firm foothold, and is a strong contender for the extreme experimental conditions of tomorrow's machines. Organized by a group from the Institute of High Energy Physics, Berlin-Zeuthen, a workshop held from 3-5 September in the nearby village of Blossin brought together experts from East and West, and from science and industry

  8. Scintillating fibres

    Energy Technology Data Exchange (ETDEWEB)

    Nahnhauer, R. [IHEP Zeuthen (Germany)

    1990-11-15

    In the search for new detector techniques, scintillating fibre technology has already gained a firm foothold, and is a strong contender for the extreme experimental conditions of tomorrow's machines. Organized by a group from the Institute of High Energy Physics, Berlin-Zeuthen, a workshop held from 3-5 September in the nearby village of Blossin brought together experts from East and West, and from science and industry.

  9. Synthesis of erbium oxide nanosheets and up-conversion properties

    DEFF Research Database (Denmark)

    Chen, X. B.; Wang, Cen; Hu, X.R.

    2011-01-01

    A novel erbium-based compound as well as Er2O3 nanosheets have been synthesized through a simple hydrothermal route. The nanosheets are of 200 nm width and 10–15 nm thickness. It is suggested that this erbium-based compound has a possible formula of Er2O5H4 with a primitive tetragonal structure (...

  10. Ablative Fractional 10 600 nm Carbon Dioxide Laser Versus Non-ablative Fractional 1540 nm Erbium-Glass Laser in Egyptian Post-acne Scar patients.

    Science.gov (United States)

    Elsaie, Mohamed L; Ibrahim, Shady M; Saudi, Wael

    2018-01-01

    Introduction: Non-ablative fractional erbium-doped glass 1540 nm and fractional ablative 10600 nm carbon dioxide lasers are regarded as effective modalities for treating acne atrophic scars. In this study, we aimed to compare the effectiveness of fractional CO 2 laser and fractional nonablative 1540 nm erbium doped glass laser in treating post acne atrophic scars in Egyptian patients. Methods: Fifty-eight patients complaining of moderate and severe acne atrophic scars were randomly divided into 2 groups of 29 patients each. Both groups were subjected to 4 treatment sessions with 3 weeks interval and were followed up for 3 months. In group A, enrolled patient sreceived C2 laser, while in group B, patients were treated with 1540 nm erbium glass fractional laser. Results: Clinical assessment revealed that the mean grades of progress and improvement were higher with fractional 10600 nm CO2 laser but with non-significant difference between both treatments ( P = 0.1). The overall patients' satisfaction with both lasers were not significantly different ( P = 0.44). Conclusion: Both fractional ablative CO2 and fractional non-ablative erbium glass lasers are good modalities for treating acne scars with a high efficacy and safety profile and good patient satisfaction. The fractional ablative laser showed higher efficacy while non-ablative laser offered less pain and shorter downtime.

  11. Optical and spectroscopic study of erbium doped calcium borotellurite glasses

    Science.gov (United States)

    Gomes, J. F.; Lima, A. M. O.; Sandrini, M.; Medina, A. N.; Steimacher, A.; Pedrochi, F.; Barboza, M. J.

    2017-04-01

    In this study, 10CaF2 - (29.9-0.4x)CaO - (60-0.6x)B2O3 - xTeO2 - 0,1Er2O3 (x = 10, 16, 22, 30 and 50 mol %) glasses were synthesized, and their optical and spectroscopic properties were investigated. X-ray diffraction, density, glass transition temperature (Tg), crystallization temperature (Tx), refraction index, luminescence, radiative lifetime and optical absorption measurements were carried out. Molar volume (Vm), thermal stability (Tx-Tg), electronic polarizability (αm), optical bang gap energy (Eg) and Judd-Ofelt (JO) parameters Ωt (2,4,6) were also calculated. The results are discussed in terms of tellurium oxide content. The increase of TeO2 in the glasses composition increases density, refractive index and electronic polarizability. The optical band gap energy decreases varying from 3.37 to 2.71 eV for the glasses with 10 and 50 mol% of TeO2, respectively. The optical absorption coefficient spectra show characteristic bands of Er3+ ions. Furthermore, these spectra in NIR region show a decrease of hydroxyl groups as a function of TeO2 addition. Luminescence intensity and radiative lifetimes at 1530 nm show an increasing with the TeO2 content. The JO parameters of Er:CaBTeX glasses follow the trend Ω2 > Ω4 > Ω6 and the quality factor values (Ω4/Ω6) were between 1.37 and 3.07. By comparing the measured lifetime with the calculated radiative decay time, quantum efficiency was calculated. The luminescence emission intensity at 1530 nm decreases with the increase of temperature. The lifetime values show a slight trend to decrease with the temperature increase, from 300 to 420 K, for all the samples.

  12. Planar waveguide amplifiers and laser in erbium doped silica

    DEFF Research Database (Denmark)

    Guldberg-Kjær, Søren Andreas; Kristensen, Martin

    1999-01-01

    with UV-light and that permanent Bragg-gratings can be induced. Planar waveguide lasers with integrated Bragg-gratings are manufactured and characterised. It is shown that linewidths below 125 kHz and output powers around 0.5 mW can be obtained, and that the manufactured lasers are resistant to mechanical...... lightwave circuits, as well as provide the gain medium for integrated planar waveguide lasers. The work and the obtained results are presented in this thesis: The manufacturing of silica thin films is described and it is shown that the refractive index o fthe films can be controlled by germanium co...... as well as thermal influence. A simple method for producing an array of planar waveguide lasers is presented and it is shown that the difference in output wavelength of the individual lasers can be controlled with great accuracy....

  13. Latest developments in silica fibre luminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D. A.; Abdul S, S. F.; Jafari, S. M.; Alanazi, A. [University of Surrey, Department of Physics, GU2 7XH Guildford, Surrey (United Kingdom); Amouzad M, G. [University of Malaya, Faculty of Engineering, Department of Electrical Engineering, Integrated Lightwave Research Group, 50603 Kuala Lumpur (Malaysia); Addul R, H. A.; Mizanur R, A. K. M.; Zubair, H. T.; Begum, M.; Yusoff, Z.; Omar, N. Y. M. [Multimedia University, Faculty of Engineering, 2010 Cyberjaya, Selangor (Malaysia); Maah, M. J. [University of Malaya, Department of Chemistry, 50603 Kuala Lumpur (Malaysia); Collin, S. [National Physical Laboratory, Hampton Road, Teddington, TW11 OLW Middlesex (United Kingdom); Mat-Sharif, K. A.; Muhd-Yassin, S. Z.; Zulkifli, M. I., E-mail: d.a.bradley@surrey.ac.uk [Telekom Malaysia Research and Development Sdn Bhd., 63000 Cyberjaya, Selangor (Malaysia)

    2015-10-15

    Full text: Using tailor made sub-mm diameter doped-silica fibres, we are carrying out luminescence dosimetry studies for a range of situations, including thermoluminescence (Tl)investigations on a liquid alpha source formed of {sup 223}RaCl (the basis of the Bayer Health care product Xofigo), the Tl response to a 62 MeV proton source and Tl response to irradiation from an {sup 241}Am-Be neutron source. In regard to the former, in accord with the intrinsic high linear energy transfer (Let) and short path length (<100 um) of the α-particles in calcified tissue, the product is in part intended as a bone-seeking radionuclide for treatment of metastatic cancer, offering high specificity and efficacy. The Tl yield of Ge-doped SiO{sub 2} fibres has been investigated including for photonic crystal fibre un collapsed, flat fibres and single mode fibres, these systems offering many advantages over conventional passive dosimetry types. In particular, one can mention comparable and even superior sensitivity, an effective atomic number Z{sub eff} of the silica dosimetric material close to that of bone, and the glassy nature of the fibres offering the additional advantage of being able to place such dosimeters directly into liquid environments. Finally we review the use of our tailor made fibres for on-line radioluminescence measurements of radiotherapy beams. The outcome from these various lines of research is expected to inform development of doped fiber radiation dosimeters of versatile utility, ranging from clinical applications through to industrial studies and environmental evaluations. (Author)

  14. WORKSHOP: Scintillating fibre detectors

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Scintillating fibre detector development and technology for the proposed US Superconducting Supercollider, SSC, was the subject of a recent workshop at Fermilab, with participation from the high energy physics community and from industry. Sessions covered the current status of fibre technology and fibre detectors, new detector applications, fluorescent materials and scintillation compositions, radiation damage effects, amplification and imaging structures, and scintillation fibre fabrication techniques

  15. Development of tailor-made silica fibres for TL dosimetry

    International Nuclear Information System (INIS)

    Bradley, D.A.; Abdul Sani, Siti F.; Alalawi, Amani I.; Jafari, S.M.; Noor, Noramaliza M.; Hairul Azhar, A.R.; Mahdiraji, Ghafour Amouzad; Tamchek, Nizam; Ghosh, S.; Paul, M.C.; Alzimami, Khalid S.; Nisbet, A.; Maah, M.J.

    2014-01-01

    The Ge dopant in commercially available silica optical fibres gives rise to appreciable thermoluminscence (TL), weight-for-weight offering sensitivity to MV X-rays several times that of the LiF dosimeter TLD100. The response of these fibres to UV radiation, X-rays, electrons, protons, neutrons and alpha particles, with doses from a fraction of 1 Gy up to 10 kGy, have stimulated further investigation of the magnitude of the TL signal for intrinsic and doped SiO 2 fibres. We represent a consortium effort between Malaysian partners and the University of Surrey, aimed at production of silica fibres with specific TL dosimetry applications, utilizing modified chemical vapour deposition (MCVD) doped silica–glass production and fibre-pulling facilities. The work is informed by defect and dopant concentration and various production dependences including pulling parameters such as temperature, speed and tension; the fibres also provide for spatial resolutions down to <10 µm, confronting many limitations faced in use of conventional (TL) dosimetry. Early results are shown for high spatial resolution (∼0.1 mm) single-core Ge-doped TL sensors, suited to radiotherapy applications. Preliminary results are also shown for undoped flat optical fibres of mm dimensions and Ge-B doped flat optical fibres of sub-mm dimensions, with potential for measurement of doses in medical diagnostic applications. - Highlights: • Optical fibres tailor-made for TL dosimetry. • Sensitive to diagnostic as well as therapy doses in medicine. • Preform and fibre pulling facilities. • Relative TL and EPR measurements

  16. Three mode Er3+ ring-doped fiber amplifier for mode-division multiplexed transmission

    NARCIS (Netherlands)

    Jung, Y.; Kang, Q.; Sleiffer, V.A.J.M.; Inan, B.; Kuschnerov, M.; Veljanovski, V.; Corbett, B.; Winfield, R.; Li, Z.; Teh, P.S.; Dhar, A.; Sahu, J.K.; Poletti, F.; Alam, S.U.; Richardson, D.J.

    2013-01-01

    We successfully fabricate three-mode erbium doped fiber with a confined Er3+ doped ring structure and experimentally characterize the amplifier performance with a view to mode-division multiplexed (MDM) transmission. The differential modal gain was effectively mitigated by controlling the relative

  17. Influence of annealing temperature on erbium ion electroluminescence in Si : (Er,O) diodes with (111) substrate orientation

    CERN Document Server

    Sobolev, N A; Nikolaev, Y A

    2001-01-01

    A study has been made of the influence of temperature of the second annealing that promotes formation of optically and electrically active centers o the erbium ion electroluminescence at lambda approx = 1.54 mu m wavelength in (111) Si : (Er,O) diodes. Doping has been performed by implantation of erbium and oxygen ions at 2.0, 1.6 MeV and 0.28, 0.22 MeV energies and 3 x 10 sup 1 sup 4 cm sup - sup 2 and 3 x 10 sup 1 sup 5 cm sup - sup 2 doses, respectively. The room temperature electroluminescence intensity under the breakdown regime increases with increasing annealing temperature from 700 to 950 deg C. After annealing in the range of 975-1100 deg C, erbium electroluminescence under the breakdown regime is not observed due to appearance of microplasmas. The injection electroluminescence intensity at 80 K decreases with increasing temperature from 700 to 1100 deg C

  18. Regeneration of irradiated optical fibres by photo-bleaching?

    International Nuclear Information System (INIS)

    Henschel, H.; Koehn, O.

    1999-01-01

    It is known that a light power between 0,1 and 20 μW caused bleaching of colour centres, which implies a reduction of induced loss. Older fibres especially those with a core made of undoped, low OH silica, experience tremendous photo-bleaching. Light of shorter wavelengths has a higher bleaching efficiency than that of longer wavelengths and same light intensity. The investigations have demonstrated that the injection of photo-bleaching light of shorter wavelength and higher intensity can distinctly decrease the radiation-induced loss of Ge-doped fibres, especially at low temperatures. Another possibility to apply photo-bleaching by short wavelength is to regenerate fibres that are permanently installed in radiation environments. Modern undoped multi-mode (MM) step index (Si), Ge-doped MM graded index (Gi) and Ge-doped single-mode (SM) fibres that had been irradiated were submitted to bleaching light. In this article it is shown how loss reduction and necessary bleaching time depend on wavelength and intensity of the bleaching light, on fibre length (bleaching time) and on radiation dose. These results are promising for the regeneration of optical fibres in facilities where the fibres cannot be replaced easily by new ones. (A.C.)

  19. Erbium: alternative poison? stabilisation additive? what future?

    International Nuclear Information System (INIS)

    Porta, J.; Asou, M.

    2001-01-01

    Erbium was proposed as alternative poison to gadolinium at a very early stage. The potential interest of this poison compared to gadolinium is that it presents a relatively low ( 167 Er) absorption cross section in the thermal range and a non-negligible resonance integral that lead to a relatively slow consumption kinetic rather adapted to long or even very long cycles. The poisoning mode adapted to this poison, homogeneous in low concentration (< 3 %), does not downgrade the power distribution, on the one hand, as the absorption is low and spatially homogeneous, and the thermal conductivity, on the other hand, as the addition in the fuel oxide is in low quantity. A review of knowledge acquired as regards Er, from the 1960's to now, is presented. (authors)

  20. Advances in laser technology and fibre-optic delivery systems in lithotripsy.

    Science.gov (United States)

    Fried, Nathaniel M; Irby, Pierce B

    2018-06-08

    The flashlamp-pumped, solid-state holmium:yttrium-aluminium-garnet (YAG) laser has been the laser of choice for use in ureteroscopic lithotripsy for the past 20 years. However, although the holmium laser works well on all stone compositions and is cost-effective, this technology still has several fundamental limitations. Newer laser technologies, including the frequency-doubled, double-pulse YAG (FREDDY), erbium:YAG, femtosecond, and thulium fibre lasers, have all been explored as potential alternatives to the holmium:YAG laser for lithotripsy. Each of these laser technologies is associated with technical advantages and disadvantages, and the search continues for the next generation of laser lithotripsy systems that can provide rapid, safe, and efficient stone ablation. New fibre-optic approaches for safer and more efficient delivery of the laser energy inside the urinary tract include the use of smaller-core fibres and fibres that are tapered, spherical, detachable or hollow steel, or have muzzle brake distal fibre-optic tips. These specialty fibres might provide advantages, including improved flexibility for maximal ureteroscope deflection, reduced cross section for increased saline irrigation rates through the working channel of the ureteroscope, reduced stone retropulsion for improved stone ablation efficiency, and reduced fibre degradation and burnback for longer fibre life.

  1. Microgel polymer composite fibres

    OpenAIRE

    Kehren, Dominic

    2014-01-01

    In this thesis some novel ideas and advancements in the field of polymer composite fibres, specifically microgel-based polymer composite fibres have been achieved. The main task was to investigate and understand the electrospinning process of microgels and polymers and the interplay of parameter influences, in order to fabricate reproducible and continuously homogenous composite fibres. The main aim was to fabricate a composite material which combines the special properties of polymer fibres ...

  2. Fun with Optical Fibres

    Science.gov (United States)

    Alti, Kamlesh

    2017-01-01

    Optical fibres play a very crucial role in today's technologies. Academic courses in optical fibres start at the undergraduate level. Nevertheless, student's curiosity towards optical fibres starts from the school level. In this paper, some fun experiments have been designed for both school and college students, which have some concrete…

  3. Special fibres and components

    DEFF Research Database (Denmark)

    Bunge, C.-A.; Woyessa, Getinet; Bremer, K.

    2017-01-01

    In this chapter we present more specific fibre types for particular applications. Starting with the multi-core fibre, which can be used as a substitution for ordinary SI-POF transmission fibres, but with better bending losses, over the ever increasing range of micro-structured POF for diverse sen...

  4. Photonic Crystal Fibres

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Broeng, Jes; Sanchez Bjarklev, Araceli

    Photonic crystal fibres represent one of the most active research areas today in the field of optics. The diversity of applications that may be addressed by these fibres and their fundamental appeal, by opening up the possibility of guiding light in a radically new way compared to conventional...... optical fibres, have spun an interest from almost all areas of optics and photonics. The aim of this book is to provide an understanding of the different types of photonic crystal fibres and to outline some of the many new and exciting applications that these fibres offer. The book is intended for both...

  5. Fibre illumination system

    DEFF Research Database (Denmark)

    2012-01-01

    Source: EP2426402A The invention relates to a fibre illumination module and system for the collection and delivery of daylight for illumination purposes. The fibre illumination module comprises a plurality of collector elements, each collector element comprising an input fibre having a first end......-directional arrangement. The fibre illumination system comprises a fibre illumination module of the above-mentioned type. By the invention, daylight may be exploited for the illumination of remote interior spaces of buildings in order to save energy, and improve the well-being of users in both housing and working...

  6. Photoluminescence at 1.54 {mu}m of Er-doped hydrogenated amorphous silicon

    Energy Technology Data Exchange (ETDEWEB)

    Bresler, Mikhail; Gusev, Oleg; Kuznetsov, Alexey; Kudoyarova, Vera; Terukov, Evgenii; Yassievich, Irina [A.F. Ioffe Physico-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation); Fuhs, Walther [Hahn-Meitner Institut, Abteilung Photovoltaik, Rudower Chaussee 5, D-12489 Berlin (Germany); Ulber, Isabell; Weiser, Gerhard [Philipps-Universitat Marburg, Fachbereich Physik, D-35032 Marburg (Germany)

    1998-05-11

    Photoluminescence (PL) and light absorption of Er-doped amorphous hydrogenated silicon samples are measured at 77-300K. The temperature dependence of luminescence of erbium ions in a-Si:H(Er) is compared with that of intrinsic PL of a-Si:H. The lifetime of excited erbium ions in this amorphous matrix changes from 20 to 8 {mu}s in this temperature range. We propose a defect-related Auger excitation (DRAE) mechanism of erbium luminescence and demonstrate that it is consistent with the whole set of our experimental results. The temperature quenching of the erbium luminescence observed above 200K, with the activation energy of 250 meV, results from the competition of the DRAE and multiphonon nonradiative defect processes for D{sup 0}+e>D{sup -} transition

  7. The effect of erbium on the adsorption and photodegradation of orange I in aqueous Er3+-TiO2 suspension

    International Nuclear Information System (INIS)

    Liang Chunhua; Hou Meifang; Zhou Shungui; Li Fangbai; Liu Chengshuai; Liu Tongxu; Gao Yuanxue; Wang Xugang; Lue Jialong

    2006-01-01

    Pure TiO 2 and erbium ion-doped TiO 2 (Er 3+ -TiO 2 ) catalysts prepared by the sol-gel method were characterized by means of XRD and diffusive reflectance spectra (DRS). The XRD results showed that erbium ion doping could enhance the thermal stability of TiO 2 and inhibit the increase of the crystallite size, and the DRS results showed that the optical absorption edge slightly shifted to red direction owing to erbium ion doping and the Er 3+ -TiO 2 catalysts had three typical absorption peaks located at 490, 523 and 654 nm owing to the transition of 4f electron from 4 I 15/2 to 4 F 7/2 , 2 H 11/2 and 4 F 9/2 . With a purpose of azo dyes degradation, orange I was used as a model chemical. And the adsorption isotherm, degradation and mineralization of orange I were investigated in aqueous suspension of pure TiO 2 or Er 3+ -TiO 2 catalysts. The results showed that Er 3+ -TiO 2 catalysts had higher adsorption equilibrium constants and better adsorption capacity than pure TiO 2 . The adsorption equilibrium constants (K a ) of Er 3+ -TiO 2 catalysts were about twice of that of pure TiO 2 . The maximum adsorption capacity (Q max ) of 2.0% Er 3+ -TiO 2 catalyst was 13.08 x 10 -5 mol/g, which was much higher than that of pure TiO 2 with 9.03 x 10 -5 mol/g. Among Er 3+ -TiO 2 catalysts, 2.0% Er 3+ -TiO 2 catalyst achieved the highest Q max and K a values. The kinetics of the orange I degradation using different Er 3+ -TiO 2 catalysts were also studied. The results demonstrated that the degradation and mineralization of orange I under both UV radiation and visible light were more efficient with Er 3+ -TiO 2 catalyst than with pure TiO 2 , and an optimal dosage of erbium ion at 1.5% achieved the highest degradation rate. The higher photoactivity under visible light might be attributable to the transitions of 4f electrons of Er 3+ and red shifts of the optical absorption edge of TiO 2 by erbium ion doping

  8. Compact erbium lasers in the IR photorefractive keratectomy (PRK)

    Science.gov (United States)

    Liu, Baining; Eichler, Hans J.; Sperlich, O.; Holschbach, A.; Kayser, M.

    1996-09-01

    Erbium lasers deliver laser radiation near 3 micrometers and are a promising alternative to excimer laser photorefractive keratectomy (UV-PRK). In addition to easier handling due to all solid state technology, especially when operated in the fundamental mode, IR-PRK eliminates the potential of mutagenic side effects associated with UV-PRK. However, a successful IR-PRK for the clinic treatment in the near future demands both technological development of erbium lasers in different operation modes and clinical investigation of interaction between 3 micrometers radiation and human corneas. The excellent cooperation between university, company and hospital makes this possible. Uncoated thin plates made from infrared materials were found to be effective etalon reflectors with high damage threshold as high as 1 GW/cm2 for erbium lasers. Four kinds of such reflectors were successfully tested in Q-switched Er:YAG-laser at 2.94 micrometers and Er:Cr:YSGG-laser at 2.80 micrometers. Very stable operation of our erbium lasers with high output energy both in free-running and Q-switched modes is realized. First infrared photorefractive keratectomy (IR-PRK) for myopic correction in human corneas by a free-running erbium laser based on our new construction concepts was achieved.

  9. Activation of erbium films for hydrogen storage

    International Nuclear Information System (INIS)

    Brumbach, Michael T.; Ohlhausen, James A.; Zavadil, Kevin R.; Snow, Clark S.; Woicik, Joseph C.

    2011-01-01

    Hydriding of metals can be routinely performed at high temperature in a rich hydrogen atmosphere. Prior to the hydrogen loading process, a thermal activation procedure is required to promote facile hydrogen sorption into the metal. Despite the wide spread utilization of this activation procedure, little is known about the chemical and electronic changes that occur during activation and how this thermal pretreatment leads to increased rates of hydrogen uptake. This study utilized variable kinetic energy X-ray photoelectron spectroscopy to interrogate the changes during in situ thermal annealing of erbium films, with results confirmed by time-of-flight secondary ion mass spectrometry and low energy ion scattering. Activation can be identified by a large increase in photoemission between the valence band edge and the Fermi level and appears to occur over a two stage process. The first stage involves desorption of contaminants and recrystallization of the oxide, initially impeding hydrogen loading. Further heating overcomes the first stage and leads to degradation of the passive surface oxide leading to a bulk film more accessible for hydrogen loading.

  10. Synthesis and luminescence properties of erbium silicate thin films

    International Nuclear Information System (INIS)

    Miritello, Maria; Lo Savio, Roberto; Iacona, Fabio; Franzo, Giorgia; Bongiorno, Corrado; Priolo, Francesco

    2008-01-01

    We have studied the structure and the room temperature luminescence of erbium silicate thin films deposited by rf magnetron sputtering. Films deposited on silicon oxide layers are characterized by good structural properties and excellent stability. The optical properties of these films are strongly improved by rapid thermal annealing processes performed in the range of temperature 800-1250 deg. C. In fact through the reduction of the defect density of the material, a very efficient room temperature photoluminescence at 1535 nm is obtained. We have also investigated the influence of the annealing ambient, by finding that treatments in O 2 atmosphere are significantly more efficient in improving the optical properties of the material with respect to processes in N 2 . Upconversion effects become effective only when erbium silicate is excited with high pump powers. The evidence that all Er atoms (about 10 22 cm -3 ) in erbium silicate films are optically active suggests interesting perspectives for optoelectronic applications of this material

  11. Modification of the electronic properties of As2Se3 films by erbium using ion-plasma sputtering method

    International Nuclear Information System (INIS)

    Prikhodko, O.Yu.; Sarsembinov, Sh.Sh.; Ryaguzov, A.P.; Maksimova, S.Ya.; Chuprynin, A.S.

    2003-01-01

    At present one of the vital problems of semiconductor materials studies is production of new light emitting materials for fiber optics, namely for light-emitting diode, emitting at room temperature in the range of minimum absorption of quartz optic fiber. It is well-known that heterostructures based on amorphous semiconductors, containing large concentrations of rare-earth elements have such properties. The method of ion-plasma co-sputtering (IPCM) of the original and doping materials allows us to obtain amorphous semiconductor films with large impurity concentration. This method was used to produce amorphous films of chalcogenide vitreous semiconductors (ChVS), doped with impurities of different chemical nature. But the capability of IPCM for ChVS doping with rare-earth elements has not been studied well yet. Therefore it is interesting to obtain amorphous films of arsenic selenide doped with erbium using IPCM and study its electronic properties. The films were produced using high frequency (13.56 MHz) ion-plasma co-sputtering of combined target of vitreous As 2 Se 3 and a metal. The sputtering of the target was conducted in argon atmosphere. Er concentration in the films varied between 0 and 4 atomic percent. Amorphism of the structure of the obtained films was monitored using X-ray diffraction methods. Electrical and optical properties of Er-doped As 2 Se 3 films and the charge carrier transportation processes were studied. It was determined that doped films significantly differ from the pure ones in the values of main electronic parameters: conductivity, energy activation of conductivity, optical band-gap, drift mobility of electrons and holes and mobility activation energy. Note that common rules of change of electronic parameters of As 2 Se 3 films affected by Er doping agree with the rules, established during modification of As 2 Se 3 films with dopes of transition metals with incomplete 3d-shell (Fe, Ni). Analysis of the obtained results showed that doing

  12. Properties of bright solitons in averaged and unaveraged models for SDG fibres

    Science.gov (United States)

    Kumar, Ajit; Kumar, Atul

    1996-04-01

    Using the slowly varying envelope approximation and averaging over the fibre cross-section the evolution equation for optical pulses in semiconductor-doped glass (SDG) fibres is derived from the nonlinear wave equation. Bright soliton solutions of this equation are obtained numerically and their properties are studied and compared with those of the bright solitons in the unaveraged model.

  13. Dysprosium (holmium) determination in the presence of erbium and dysprosium (holmium, erbium) determination in the presence of cerium

    International Nuclear Information System (INIS)

    Tolubara, A.I.; Kochubej, A.I.; Usatenko, Yu.I.

    1978-01-01

    Effect of salicylic acid upon complex formation in the systems REE - boronsulfoalizarinate, REE - oxine and REE - boronsulfoalizarinate - oxine is investigated. Comparison of optical characteristics of the above systems in the absence and in the presence of salicylic acid is carried out. It is established that in all the cases the effect of salicylic acid depends both on the nature of REE and the ratio of all the components of the system. Under certain conditions the given dependence is observed only for erbium complexes. Extraction-photometric methods of dysprosium and holmium determination in the presence of equal erbium amounts, as well as holmium and erbium determination in the presence of cerium equal amounts is developed

  14. Dysprosium (holmium) determination in the presence of erbium and dysprosium (holmium, erbium) determination in the presence of cerium

    Energy Technology Data Exchange (ETDEWEB)

    Tolubara, A I; Kochubei, A I; Usatenko, Yu I

    1978-01-01

    Effect of salicylic acid upon complex formation in the systems REE - boronsulfoalizarinate, REE - oxine and REE - boronsulfoalizarinate - oxine is investigated. Comparison of optical characteristics of the above systems in the absence and in the presence of salicylic acid is carried out. It is established that in all the cases the effect of salicylic acid depends both on the nature of REE and the ratio of all the components of the system. Under certain conditions the given dependence is observed only for erbium complexes. Extraction-photometric methods of dysprosium and holmium determination in the presence of equal erbium amounts, as well as holmium and erbium determination in the presence of cerium equal amounts is developed.

  15. HIPPI and Fibre Channel

    International Nuclear Information System (INIS)

    Tolmie, D.E.

    1992-01-01

    The High-Performance Parallel Interface (HIPPI) and Fibre Channel are near-gigabit per second data communications interfaces being developed in ANSI standards Task Group X3T9.3. HIPPI is the current interface of choice in the high-end and supercomputer arena, and Fibre Channel is a follow-on effort. HIPPI came from a local area network background, and Fibre Channel came from a mainframe to peripheral interface background

  16. Optically active erbium centers in silicon

    NARCIS (Netherlands)

    Przybylinska, H; Jantsch, W; SuprunBelevitch, Y; Stepikhova, M; Palmetshofer, L; Hendorfer, G; Kozanecki, A; Wilson, RJ; Sealy, BJ

    1996-01-01

    The intra-4f transition close to 1.54 mu m of Er implanted into Si shows rich fine structure due to the crystal field of different defect types. Making use of the influence of implantation and annealing parameters, additional doping, temperature, and excitation power, we identify groups of lines

  17. Band gap and polarizability of boro-tellurite glass: Influence of erbium ions

    Science.gov (United States)

    Said Mahraz, Zahra Ashur; Sahar, M. R.; Ghoshal, S. K.

    2014-08-01

    Understanding the influence of rare earth ions in improving the structural and optical properties of inorganic glasses are the key issues. Er3+-doped zinc boro-tellurite glasses with composition 30B2O3-10ZnO-(60-x) TeO2-xEr2O3 are prepared (x = 0, 0.5, 1, 1.5 and 2 mol%) using melt quenching technique. The physical and optical characterizations are measured by density and UV-Vis-IR absorption spectroscopy. The color of the glass changed from light yellow to deep pink due to the introduction of Er3+ ions. The maximum density is found to be ∼4.73 g cm-3 for 1 mol% of Er3+ doping. The variations in the polarizability (6.7-6.8 cm3) and the molar volume (27.987-28.827 cm3 mol-1) with dopant concentration are ascribed to the formation of non-bridging oxygen. This observation is consistent with the alteration of number of bonds per unit volume. The direct and indirect optical band gaps are increased while the phonon cut-off wavelength and Urbach energy decreased with the increase of erbium content. A high density and wide transparency range in VIS-IR area are achieved. Our results on high refractive index (∼2.416) and polarizability suggest that these glasses are potential for photonics, solid state lasers and communications devices.

  18. Gettering of carbon dioxide by erbium thin films

    International Nuclear Information System (INIS)

    Mehrhoff, T.K.

    1980-01-01

    The interaction of carbon dioxide and erbium thin films is characterized at 300 to 900 0 C and 5 x 10 -7 torr. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C, preceded by desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface. The sticking coefficients were plotted as a function of Langmuirs of carbon dioxide exposure. Between 400 and 600 0 C, the length of the exposure was found to be more important than the temperature of the exposure in determining the sticking coefficient. Some evolution of carbon monoxide was noted particularly in the 400 to 500 0 C region. An 80% conversion of carbon dioxide to carbon monoxide was measured at 500 0 C. The film pumping speeds were compared with published vapor pressure data for erbium. This comparison indicated that a significant portion of the pumping action observed at temperatures of 800 0 C and above was due to evaporation of erbium metal

  19. Erbium:ytterbium fiber-laser system delivering watt-level femtosecond pulses using divided pulse amplification

    Science.gov (United States)

    Herda, Robert; Zach, Armin

    2015-03-01

    We present an Erbium:Ytterbium codoped fiber-amplifer system based on Divided-Pulses-Amplification (DPA) for ultrashort pulses. The output from a saturable-absorber mode-locked polarization-maintaining (PM) fiber oscillator is amplified in a PM normal-dispersion Erbium-doped fiber. After this stage the pulses are positively chirped and have a duration of 2.0 ps at an average power of 93 mW. A stack of 5 birefringent Yttrium-Vanadate crystals divides these pulses 32 times. We amplify these pulses using a double-clad Erbium:Ytterbium codoped fiber pumped through a multimode fiber combiner. The pulses double pass the amplifier and recombine in the crystals using non-reciprocal polarization 90° rotation by a Faraday rotating mirror. Pulses with a duration of 144 fs are obtained after separation from the input beam using a polarizing beam splitter cube. These pulses have an average power of 1.85 W at a repetition rate of 80 MHz. The generation of femtosecond pulses directly from the amplifier was enabled by a positively chirped seed pulse, normally dispersive Yttrium-Vanadate crystals, and anomalously dispersive amplifier fibers. Efficient frequency doubling to 780 nm with an average power of 725 mW and a pulse duration of 156 fs is demonstrated. In summary we show a DPA setup that enables the generation of femtosecond pulses at watt-level at 1560 nm without the need for further external dechirping and demonstrate a good pulse quality by efficient frequency doubling. Due to the use of PM fiber components and a Faraday rotator the setup is environmentally stable.

  20. Fibre-concrete container

    International Nuclear Information System (INIS)

    2000-01-01

    In this leaflet the fibre-concrete container for radioactive wastes is described. The fibre container is made of fibre-concrete that contains cement, aggregate, sand, filter, flame-silica, super-plastificator, water and scattered metal fibres. The fibre-concrete container has a dice shape with outer dimension 1.7 x 1.7 x 1.7 m. It is mounted of a container body, a container cover and two caps. Total weight of container is 4,240 kg, maximum weight of loaded container do not must exceed 15,000 kg. The physical and mechanical properties of the fibre-concrete container are described in detail. The fibre-concrete container manufactured for storing of low and intermediate radioactive wastes. A fibre-concrete container utilization to store of radioactive wastes solves these problems: increase of stability of stored packages of radioactive waste; watertightness within 300 years at least; static stability of bearing space; better utilization of bearing spaces; insulation of radioactive waste in a case of seismic and geological event; increase of fire resistance; and transport of radioactive waste

  1. POLARISATION PRESERVING OPTICAL FIBRE

    DEFF Research Database (Denmark)

    2000-01-01

    . This cladding structure provides polarisation preserving properties to the optical fibre. Optical fibres using this technology may have claddings with elements placed non-periodically as well as in a two-dimensional periodic lattice - such as cladding providing Photonic Band Gap (PBG) effects....

  2. Pure chiral optical fibres.

    Science.gov (United States)

    Poladian, L; Straton, M; Docherty, A; Argyros, A

    2011-01-17

    We investigate the properties of optical fibres made from chiral materials, in which a contrast in optical activity forms the waveguide, rather than a contrast in the refractive index; we refer to such structures as pure chiral fibres. We present a mathematical formulation for solving the modes of circularly symmetric examples of such fibres and examine the guidance and polarisation properties of pure chiral step-index, Bragg and photonic crystal fibre designs. Their behaviour is shown to differ for left- and right-hand circular polarisation, allowing circular polarisations to be isolated and/or guided by different mechanisms, as well as differing from equivalent non-chiral fibres. The strength of optical activity required in each case is quantified.

  3. FibreBags vs. FibreCaps for acid and neutral detergent fibre analysis

    OpenAIRE

    Koivisto , Jason

    2003-01-01

    International audience; A new procedure for determining acid detergent fibre and neutral detergent fibre (ADF and NDF) was developed to reduce the need for filtration and to allow for batch processing of forage samples. The FibreBag system is an economically necessary evolution of the earlier FibreCap system. The purpose of this enquiry was to determine if the FibreBag is a suitable replacement for the FibreCap. The FibreBag method produced very similar results to the FibreCap system of analy...

  4. Rare earth doped nanoparticles in organic and inorganic host materials for application in integrated optics

    NARCIS (Netherlands)

    Dekker, R.; Hilderink, L.T.H.; Diemeer, Mart; Stouwdam, J.W.; Sudarsan, V; van Veggel, F.C.J.M.; Driessen, A.; Worhoff, Kerstin; Misra, D; Masscher, P.; Sundaram, K.; Yen, W.M.; Capobianco, J.

    2006-01-01

    The preparation and the optical properties of lanthanum fluoride (LaF3) nanoparticles doped with erbium and neodymium will be discussed. Organic and inorganic materials in the form of polymers and sol-gels were used to serve as the hosts for the inorganic nanoparticles, respectively. The organic

  5. Towards rare-earth-ion-doped Al2O3 active integrated optical devices

    OpenAIRE

    Ay, F.; Bradley, J.; Worhoff, Kerstin; Pollnau, Markus

    2007-01-01

    Aluminum oxide planar waveguides with low loss (0.11 dB/cm at 1523 nm) are fabricated. Channel waveguides are obtained by reactive ion etching. Erbium-doped layers show no upconversion luminescence, a hint that ion clustering is small.

  6. Modeling of Yb3+-sensitized Er3+-doped silica waveguide amplifiers

    DEFF Research Database (Denmark)

    Lester, Christian; Bjarklev, Anders Overgaard; Rasmussen, Thomas

    1995-01-01

    A model for Yb3+-sensitized Er3+-doped silica waveguide amplifiers is described and numerically investigated in the small-signal regime. The amplified spontaneous emission in the ytterbium-band and the quenching process between excited erbium ions are included in the model. For pump wavelengths...

  7. A Pilot Study of Skin Resurfacing Using the 2,790-nm Erbium:YSGG Laser System.

    Science.gov (United States)

    Rhie, Jong Won; Shim, Jeong Su; Choi, Won Seok

    2015-01-01

    The erbium:yttrium scandium gallium garnet (Er:YSGG) laser differs from other laser techniques by having a faster and higher cure rate. Since the Er:YSGG laser causes an appropriate proportion of ablation and coagulation, it has advantages over the conventional carbon dioxide (CO2) laser and the erbium-doped yttrium aluminum garnet (Er:YAG) laser, including heating tendencies and explosive vaporization. This research was conducted to explore the effects and safety of the Er:YSGG laser. Twenty patients participated in the pilot study of a resurfacing system using a 2,790-nm Er:YSGG laser. All patients received facial treatment by the 2,790-nm Er:YSGG laser system (Cutera) twice with a 4-week interval. Wrinkle reduction, reduction in pigment inhomogeneity, and improvement in tone and texture were measured. Study subjects included 15 women and five men. Re-epithelization occurred in all subjects 3 to 4 days after treatment, and wrinkle reduction, reduction in pigment inhomogeneity, and improvement in tone and texture within 6 months of treatment. The 2,790-nm YSGG laser technique had fewer complications and was effective in the improvement of scars, pores, wrinkles, and skin tone and color with one or two treatments. We expect this method to be effective for people with acne scars, pore scars, deep wrinkles, and uneven skin texture and color.

  8. A Pilot Study of Skin Resurfacing Using the 2,790-nm Erbium:YSGG Laser System

    Directory of Open Access Journals (Sweden)

    Jong Won Rhie

    2015-01-01

    Full Text Available BackgroundThe erbium:yttrium scandium gallium garnet (Er:YSGG laser differs from other laser techniques by having a faster and higher cure rate. Since the Er:YSGG laser causes an appropriate proportion of ablation and coagulation, it has advantages over the conventional carbon dioxide (CO2 laser and the erbium-doped yttrium aluminum garnet (Er:YAG laser, including heating tendencies and explosive vaporization. This research was conducted to explore the effects and safety of the Er:YSGG laser.MethodsTwenty patients participated in the pilot study of a resurfacing system using a 2,790-nm Er:YSGG laser. All patients received facial treatment by the 2,790-nm Er:YSGG laser system (Cutera twice with a 4-week interval. Wrinkle reduction, reduction in pigment inhomogeneity, and improvement in tone and texture were measured.ResultsStudy subjects included 15 women and five men. Re-epithelization occurred in all subjects 3 to 4 days after treatment, and wrinkle reduction, reduction in pigment inhomogeneity, and improvement in tone and texture within 6 months of treatment.ConclusionsThe 2,790-nm YSGG laser technique had fewer complications and was effective in the improvement of scars, pores, wrinkles, and skin tone and color with one or two treatments. We expect this method to be effective for people with acne scars, pore scars, deep wrinkles, and uneven skin texture and color.

  9. Switchable dual-wavelength single-longitudinal-mode erbium fiber laser utilizing a dual-ring scheme with a saturable absorber

    Science.gov (United States)

    Yang, Zi-Qing; Huang, Tzu-Jung; Chang, Yao-Jen; Yeh, Chien-Hung; Chow, Chi-Wai; Chen, Jing-Heng; Chen, Kun-Huang

    2018-06-01

    In this work, we propose and demonstrate a switchable dual-wavelength erbium-doped fiber (EDF) ring laser with stable single-longitudinal-mode (SLM) output. Here, a dual-ring (DR) structure with an unpumped EDF of 2 m is designed to achieve SLM oscillation. Five fiber Bragg gratings (FBGs) are applied in the laser cavity serving as the reflective element to generate different dual-wavelength outputs. In the measurement, six sets of generated dual-wavelengths with various mode-spacing (Δλ) can be achieved via the five FBGs. Additionally, the stability performance of the proposed EDF DR laser is also demonstrated.

  10. Thermoluminescence property of LiMgF{sub 3} erbium activated phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, I.C. [Departamento de Ciencias Quimico Biologicas, Universidad de Sonora, A.P. 130, Hermosillo, Sonora 83000 (Mexico); Cruz-Zaragoza, E., E-mail: ecruz@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, Mexico 04510 D.F. (Mexico); Favalli, A. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Furetta, C. [Touro University Rome, Division of Touro College New York, Circne Gianicolense 15-17, 00153 Rome (Italy)

    2012-05-15

    The perovskite-like LiMgF{sub 3}:ErF{sub 3} pellets were obtained from the melt formed by LiF and MgF{sub 2} mixed salts in the stoichiometric ratio. The perovskite material was doped with 1, 2 and 4 mol% of ErF{sub 3} impurity. The pellets samples were {sup 60}Co gamma irradiated and their thermoluminescence (TL) properties were analyzed, i.e., dose-response, fading at RT and under UV irradiation, TL signal reproducibility, and kinetic parameters. The intensity of the TL response against irradiation dose was increased remarkably by the high concentration of impurity, and a linear dose-response was observed in the range of 1-10 Gy. The fading observed at RT was about 10-30% after 24 h from irradiation. All samples were exposed from 1 to 200 Gy gamma dose range. The TL glow peaks were found around 367-376, 438-447, 509-521, and 594-611 K, when the doped samples were 1, 2 and 4 mol% of the erbium impurity concentration. The thermoluminescence kinetics parameters of the glow curves have been analyzed using the Computerized Glow Curve Deconvolution (CGCD) method. - Highlights: Black-Right-Pointing-Pointer Perovskite-like LiMgF{sub 3} pellets were doped with 1, 2, and 4 mol% of ErF{sub 3} impurity. Black-Right-Pointing-Pointer Thermoluminescence properties and kinetics parameters were analyzed. Black-Right-Pointing-Pointer Dose-response, fading at RT and under UV irradiation and reproducibility are reported. Black-Right-Pointing-Pointer Four TL glow peaks were observed between 367 and 611 K, for all samples. Black-Right-Pointing-Pointer Glow curves have been analyzed using the CGCD method.

  11. Fibre optic microarrays.

    Science.gov (United States)

    Walt, David R

    2010-01-01

    This tutorial review describes how fibre optic microarrays can be used to create a variety of sensing and measurement systems. This review covers the basics of optical fibres and arrays, the different microarray architectures, and describes a multitude of applications. Such arrays enable multiplexed sensing for a variety of analytes including nucleic acids, vapours, and biomolecules. Polymer-coated fibre arrays can be used for measuring microscopic chemical phenomena, such as corrosion and localized release of biochemicals from cells. In addition, these microarrays can serve as a substrate for fundamental studies of single molecules and single cells. The review covers topics of interest to chemists, biologists, materials scientists, and engineers.

  12. New generation of optical fibres

    Energy Technology Data Exchange (ETDEWEB)

    Dianov, E M; Semjonov, S L; Bufetov, I A [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation)

    2016-01-31

    The growing need for information in contemporary society is the motivating force behind the development of fibre optics in general and optical fibre communications in particular. Intensive research effort has been concentrated on designing new types of optical fibres and extending their application field. This paper reviews results of research on new types of optical fibres: bismuthdoped active fibres, multicore fibres and hollow-core fibres, which can be used as key components of systems that ensure further increase in optical information transfer rate. (invited paper)

  13. DETECTORS: scintillating fibres

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    In the continual search for improved detection techniques, new materials are continually proving profitable. A good example is scintillating plastic fibres - tiny transparent threads sometimes finer than a human hair which transmit light. The narrowness and flexibility of these fibres was a major breakthrough for endoscopy - non-invasive techniques for viewing the otherwise inaccessible in surgery or machine inspection. In a more sophisticated form, these fibres find ready application in communications technology, where the goal is to transmit information rather than electrical power, replacing conventional and unwieldy current-carrying wire conductors. In particle physics, fibres have long been used to take the tiny scintillations produced when high energy particles hit fluorescent materials and 'conduct' them to photosensitive detectors some distance away

  14. Gettering of carbon dioxide by erbium thin films

    International Nuclear Information System (INIS)

    Mehrhoff, T.K.

    1980-01-01

    The interaction of carbon dioxide and erbium thin films is characterized for temperatures in the region of 300 to 900 0 C and partial pressure of carbon dioxide near 5 x 10 -7 Torr. Dynamic film pumping speeds were measured against a mercury diffusion pump of known pumping speed and conductance. A quadrupole mass spectrometer was used to monitor the carbon dioxide flow which originated from a calibrated leak in the 10 -6 standard cm 3 /s range. Data reduction was via a dedicated minicomputer with associated printer/plotter. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C. The reaction was preceded by the desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface

  15. Erbium ion implantation into different crystallographic cuts of lithium niobate

    Czech Academy of Sciences Publication Activity Database

    Nekvindová, P.; Švecová, B.; Cajzl, J.; Macková, Anna; Malinský, Petr; Oswald, Jiří; Kolitsch, A.; Špirková, J.

    2012-01-01

    Roč. 34, č. 4 (2012), s. 652-659 ISSN 0925-3467 R&D Projects: GA MŠk(CZ) LC06041; GA ČR GA106/09/0125; GA ČR(CZ) GAP106/10/1477 Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100521 Keywords : Lithium niobate * Erbium * Ion implantation * Luminescence Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.918, year: 2012

  16. Method for measuring deuterium in erbium deuteride films

    International Nuclear Information System (INIS)

    Brangan, J.R.; Thornberg, S.M.; Keenan, M.R.

    1997-09-01

    Determining the quantity of deuterium in an erbium deuteride (ErD 2 ) film is essential for assessing the quality of the hydriding process but is a challenging measurement to make. First, the ideal gas law cannot be applied directly due to high temperature (950 degrees C) and low temperature (25 degrees C) regions in the same manifold. Additionally, the metal hydride does not release all of the deuterium rapidly upon heating and metal evaporation occurs during extended heating periods. Therefore, the method developed must provide a means to compensate for temperature inhomogeneities and the amount of deuterium retained in the metal film while heating for a minimal duration. This paper presents two thermal desorption methods used to evaluate the kinetics and equilibria of the deuterium desorption process at high temperatures (950 degrees C). Of primary concern is the evaluation of the quantity of deuterium remaining in these films at the high temperature. A multiple volume expansion technique provided insight into the kinetics of the deuterium evolution and metal evaporation from the film. Finally a repeated pump-down approach yielded data that indicated approximately 10% of the deuterium is retained in the metal film at 950 degrees C and approximately 1 Torr pressure. When the total moles of deuterium determined by this method were divided by the moles of erbium determined by ICP/AES, nearly stochiometric values of 2:1 were obtained for several erbium dideuteride films. Although this work presents data for erbium and deuterium, these methods are applicable to other metal hydrides as well

  17. Fibre Concrete 2017

    Science.gov (United States)

    2017-09-01

    9th international conference on fibre reinforced concretes (FRC), textile reinforced concretes (TRC) and ultra-high performance concretes (UHPC) Preface The Fibre Concrete Conference series is held biennially to provide a platform to share knowledge on fibre reinforced concretes, textile concretes and ultra-high performance concretes regarding material properties and behaviour, technology procedures, topics of long-term behaviour, creep, durability; sustainable aspects of concrete including utilisation of waste materials in concrete production and recycling of concrete. The tradition of Fibre Concrete Conferences started in eighties of the last century. Nowadays the conference is organized by the Department of Concrete and Masonry Structures of the Czech Technical University in Prague, Faculty of Civil Engineering. The 9th International Conference Fibre Concrete 2017 had 109 participants from 27 countries all over the world. 55 papers were presented including keynote lectures of Professor Bažant, Professor Bartoš and Dr. Broukalová. The conference program covered wide range of topics from scientific research to practical applications. The presented contributions related to performance and behaviour of cement based composites, their long-term behaviour and durability, sustainable aspects, advanced analyses of structures from these composites and successful applications. This conference was organized also to honour Professor Zděnek P. Bažant on the occasion of his jubilee and to appreciate his merits and discoveries in the field of fibre reinforced composites, structural mechanics and engineering.

  18. Study of the densification of uranium-erbium system

    International Nuclear Information System (INIS)

    Freitas, Artur C.; Carvalho, Elita F.U.

    2017-01-01

    The sintering process of UO 2 -Er 2 O 3 pellets has been investigated because of its importance in the nuclear industry and the complex behavior during sintering. The present study includes the development of nuclear fuel for power reactor in order to increase the efficiency of the fuel trough longer refueling intervals. The erbium is indicated for longer cycles, which means less stops to refueling and less waste. In this work, we studied the use of erbium oxide by varying the concentrations in the range of 1-9.8%, which was added to UO 2 powder through mechanical mixing, aiming to check the rate of densification and a possible sintering blockage. The powders were pressed and sintered at 1700°C under hydrogen atmosphere. The results show a sintering blockage in the UO 2 -Er 2 O 3 system that occurs in the range of 1500-1700°C temperature. Dilatometric tests indicate a retraction of 21.87% when used Er 2 O 3 at 1% mass concentration. This shrinkage is greater than is observed with higher concentrations or even without the addition of the burnable poison, providing with a better degree of incorporation of the element erbium, resulting in pellets with density suitable for use as nuclear fuel. (author)

  19. Study of the densification of uranium-erbium system

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Artur C.; Carvalho, Elita F.U., E-mail: artur.freitas@ipen.br, E-mail: elitaucf@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    The sintering process of UO{sub 2}-Er{sub 2}O{sub 3} pellets has been investigated because of its importance in the nuclear industry and the complex behavior during sintering. The present study includes the development of nuclear fuel for power reactor in order to increase the efficiency of the fuel trough longer refueling intervals. The erbium is indicated for longer cycles, which means less stops to refueling and less waste. In this work, we studied the use of erbium oxide by varying the concentrations in the range of 1-9.8%, which was added to UO{sub 2} powder through mechanical mixing, aiming to check the rate of densification and a possible sintering blockage. The powders were pressed and sintered at 1700°C under hydrogen atmosphere. The results show a sintering blockage in the UO{sub 2}-Er{sub 2}O{sub 3} system that occurs in the range of 1500-1700°C temperature. Dilatometric tests indicate a retraction of 21.87% when used Er{sub 2}O{sub 3} at 1% mass concentration. This shrinkage is greater than is observed with higher concentrations or even without the addition of the burnable poison, providing with a better degree of incorporation of the element erbium, resulting in pellets with density suitable for use as nuclear fuel. (author)

  20. Study on erbium loading method to improve reactivity coefficients for low radiotoxic spent fuel HTGR

    Energy Technology Data Exchange (ETDEWEB)

    Fukaya, Y., E-mail: fukaya.yuji@jaea.go.jp; Goto, M.; Nishihara, T.

    2015-11-15

    Highlights: • We attempted and optimized erbium loading methods to improve reactivity coefficients for LRSF-HTGR. • We elucidated the mechanism of the improvements for each erbium loading method by using the Bondarenko approach. • We concluded the erbium loading method by embedding into graphite shaft is preferable. - Abstract: Erbium loading methods are investigated to improve reactivity coefficients of Low Radiotoxic Spent Fuel High Temperature Gas-cooled Reactor (LRSF-HTGR). Highly enriched uranium is used for fuel to reduce the generation of toxicity from uranium-238. The power coefficients are positive without the use of any additive. Then, the erbium is loaded into the core to obtain negative reactivity coefficients owing to the large resonance the peak of neutron capture reaction of erbium-167. The loading methods are attempted to find the suitable method for LRSF-HTGR. The erbium is mixed in a CPF fuel kernel, loaded by binary packing with fuel particles and erbium particles, and embedded into the graphite shaft deployed in the center of the fuel compact. It is found that erbium loading causes negative reactivity as moderator temperature reactivity, and from the viewpoint of heat transfer, it should be loaded into fuel pin elements for pin-in-block type fuel. Moreover, the erbium should be incinerated slowly to obtain negative reactivity coefficients even at the End Of Cycle (EOC). A loading method that effectively causes self-shielding should be selected to avoid incineration with burn-up. The incineration mechanism is elucidated using the Bondarenko approach. As a result, it is concluded that erbium embedded into graphite shaft is preferable for LRSF-HTGR to ensure that the reactivity coefficients remain negative at EOC.

  1. Glass ceramic fibres

    International Nuclear Information System (INIS)

    Blaschek, O.; Paulitsch, P.

    1983-01-01

    As the correlation between mineralogical phase and chemical composition influences the type of application at different high temperatures, we studied the mineralogical phases of nine crystal glass fibres of the temperature ranges 1 150 degrees Celsius (Type 1), 1 400 degrees Celsius (Type 2) and 1 500 degrees Celsius (Type 3) at various high temperatures. The methods used in the study were microscopy, X-ray diffraction, transmission electron microscopy and differential thermal analysis. The investigations showed that mullite forms in glassy fibres of the system Al 2 O 3 . SiO 2 from 850 degrees Celsius to 990 degrees Celsius as 2/1 mullite; 3/2 mullite appeared above 990 degrees Celsius besides the crystallization of cristobalite. Fibres with 95 per cent Al 2 O 3 include the phases delta-Al 2 O 3 and alpha- Al 2 O 3 and mullite. Delta- Al 2 O 3 is stable up to 1 100 degrees Celsius. Alpha-Al 2 O 3 and mullite are only stable phases at 1 400 degrees Celsius. These different crystal phases influence the quality of the technical fibre according to the stability field of glass and crystals. This study has determined that it is possible to identify different fibres from different productions by their mineralogical compositions and to relate them to the high temperature application

  2. High power, ultra-broadband supercontinuum source based on highly GeO2 doped silica fiber

    DEFF Research Database (Denmark)

    Jain, Deepak; Sidharthan, Raghuraman; Moselund, Peter M.

    2017-01-01

    We demonstrate a 74 mol % GeO2 doped fiber for mid-infrared supercontinuum generation. Experiments ensure a highest output power for a broadest spectrum from 700nm to 3200nm from this fiber, while being pumped by a broadband 4 stage Erbium fiber based MOPA. The effect of repetition rate of pump...

  3. Photoluminescence properties of Er-doped Ge–In(Ga)–S glasses modified by caesium halides

    Czech Academy of Sciences Publication Activity Database

    Ivanova, Z.G.; Zavadil, Jiří; Kostka, P.; Djouama, T.; Reinfelde, M.

    2017-01-01

    Roč. 254, č. 6 (2017), č. článku 1600662. ISSN 0370-1972 Institutional support: RVO:67985882 Keywords : caesium halides * chalcohalide glasses * erbium doping * transmission spectroscopy * photoluminiscence Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 1.674, year: 2016

  4. Photoluminescence properties of Er-doped Ge–In(Ga)–S glasses modified by caesium halides

    Czech Academy of Sciences Publication Activity Database

    Ivanova, Z.G.; Zavadil, Jiří; Kostka, Petr; Djouama, T.; Reinfelde, M.

    2017-01-01

    Roč. 254, č. 6 (2017), č. článku 1600662. ISSN 0370-1972 Institutional support: RVO:67985891 Keywords : caesium halides * chalcohalide glasses * erbium doping * transmission spectroscopy * photoluminiscence Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 1.674, year: 2016

  5. All-polarization maintaining erbium fiber laser based on carbon nanowalls saturable absorber

    Science.gov (United States)

    Kurata, Shintaro; Izawa, Jun; Kawaguchi, Norihito

    2018-02-01

    We report a soliton mode locked femtosecond oscillation with all-polarization maintaining erbuim doped fiber laser based on Carbon Nanowalls saturable absorber (CNWs SA). To improve the stability and the capability of the oscillator, the all-polarization maintaining(all-PM) fiber is generally used since PM fiber is tolerant of stretches and bends. The saturable absorber is an optical device that placed in a laser cavity to suppress continuous wave operation to promote cooperation between many modes to sustain ultrashort pulse operation. We apply CNWs for the material of SAs in our oscillator. CNWs are one of the nanocarbon materials, which are a high-aspect-ratio structure in the cross-section, where, although their width and height range in a few micrometers, the thickness is as small as ten nanometers or so. A sheet of CNWs is made up of nano-size graphite grain aggregates. Then CNWs structure is expected to have a high absorption to the incident light and large modulation depth due to a small number of carbon layers as well as CNT and Graphene. With this all-PM fiber laser oscillator based on CNWs SA, the soliton mode-locked laser oscillated with 66.3MHz repetition frequency and its spectrum width is 5.6nm in FWHM. Average output power is 8.1mW with 122.5mW laser diode pump power. In addition, the laser amplification system with erbium-doped fiber is constructed and amplifies the femtosecond pulse laser into 268.2mW and 3000mW pumping power.

  6. Multibeam Fibre Laser Cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    The appearance of the high power high brilliance fibre laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating cutting laser, the CO2-laser. However, quality problems in fibre......-laser cutting have until now limited its application in metal cutting. In this paper the first results of proof-of-principle studies applying a new approach (patent pending) for laser cutting with high brightness short wavelength lasers will be presented. In the approach, multi beam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from 2 single mode fibre lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W of single...

  7. Modelling of photonic crystal fibres

    DEFF Research Database (Denmark)

    Knudsen, Erik

    2003-01-01

    , as well as a honeycomb bandgap fibre and the first analysis of semi-periodic layered air-hole fibres. Using the modelling framework established as a basis, we provide an analysis of microbend loss, by regarding displacement of a fibre core as a stationary stochastic process, inducing mismatch between......In the presenta ph.d. work a theoretical study of aspects of modelling photonic crystal fibres was carried out. Photonic crystal fibres form a class of optical waveguides where guidance is no longer provided by a difference in refractive index between core and cladding. Instead, guidance...... is provided by an arrangement of air-holes running along the length of the fibre. Depending on the geometry of the fibre, the guiding mechanism may be either arising from the formation of a photonic bandgap in the cladding structure (photonic bandgap fibre), or by an effect resembling total internal...

  8. Mineral fibres and health

    International Nuclear Information System (INIS)

    Hoskins, J.A.

    2001-01-01

    The use of inorganic fibrous materials is a comparatively new phenomenon and was uncommon before the Industrial Revolution. Humans evolved in a comparatively fibre-free environment and consequently never fully developed the defence mechanisms needed to deal with the consequences of inhaling fibres. However, the urban environment now has an airborne fibre concentration of around 1 f.l -1 , which is a tenfold increase on the natural background. Any sample of ambient air collected indoors or outdoors will probably contain some mineral fibres, but there is little evidence that these pose any risk to human health. They come from asbestos used in brakes, glass and mineral wools used as insulation and fire proofing of buildings, gypsum from plaster and a variety of types from many sources. Few of these have the potential to do any harm. Asbestos is the only fibre of note but urban levels are insignificant compared to occupational exposures. When the health of cohorts occupationally exposed to the several types of asbestos is studied the problem can be put into perspective. Studies of workers in the chrysotile industry exposed to much higher dust levels than in a factory today show no excess lung cancer or mesothelioma. By comparison those living near crocidolite mines, let alone working in them, may develop asbestos-related disease. As always, dose is the critical factor. Chrysotile is cleared from the lungs very efficiently, only the amphiboles are well retained. The only real health problem comes from the earlier use of asbestos products that may now be old, friable and damaged and made from amphibole or mixed fibre. If though, these are still in good condition, they do not pose a health problem. Asbestos-related diseases are very rare in those not occupationally exposed. Where they exist exposure has nearly always been to crocidolite. (author)

  9. Concrete workability and fibre content

    OpenAIRE

    Vikan, Hedda

    2007-01-01

    Research report Parameters influencing the workability of fibre concrete and maximum fibre content are given in this state of the art report along with the range of fibre types available on today’s market. The study reveales that new placing techniques and production methods are crucial in order to increase fibre content and concrete strength. Achieving the same mechanical properties as traditionally reinforced concrete will probably also demand changes of the matrix. Finally, reco...

  10. Mode locking in a bismuth fibre laser by using a SESAM

    International Nuclear Information System (INIS)

    Krylov, A A; Dvoirin, V V; Mashinsky, V M; Kryukov, P G; Okhotnikov, O G; Guina, M

    2008-01-01

    By using a semiconductor saturable-absorber mirror (SESAM) optimised for operation in the spectral range from 1100 to 1200 nm, passive mode locking is obtained in a cw bismuth-doped fibre laser. Pumping was performed by a cw ytterbium-doped fibre laser at a wavelength of 1075 nm. The operation of the laser is studied by using either a fibre Bragg grating or a loop fibre Sagnac mirror as the output resonator mirror. Stable laser pulses of duration from 50 ps to 3.5 ns, depending on the output mirror type, were generated. The pulse repetition rate was 11 MHz at a wavelength of ∼1160 nm and the maximum spectral width of 2.1 nm. The maximum average output power was 7.8 mW upon pumping by 1140 mW. (control of laser radiation parameters)

  11. Single-mode optical fibres

    CERN Document Server

    Cancellieri, G

    1991-01-01

    This book describes signal propagation in single-mode optical fibres for telecommunication applications. Such description is based on the analysis of field propagation, considering waveguide properties and also some of the particular characteristics of the material fibre. The book covers such recent advances as, coherent transmissions; optical amplification; MIR fibres; polarization maintaining; polarization diversity and photon counting.

  12. Development of solvent extraction process for erbium purification

    International Nuclear Information System (INIS)

    Singh, D.K.; Anitha, M.; Vijayalakshmi, R.; Chakravartty, J.K.

    2016-01-01

    Erbium an important heavy rare earth (HRE) finds valuable application in space and nuclear energy technology. High purity erbium oxide is used as coating material for test blanket module of fusion reactor to prevent the tritium permeation. The total concentration of HRE (including Er) in only proven resource of rare earths in Indian monazite mineral is < 0.05%. Its separation from such a low concentration and also from host of other chemically similar elements like Y, Dy, Ho, Yb, Tm etc is quite difficult and challenging. A solvent extraction process employing PC88A and Aliquat336 has been developed for the purification of erbium oxide from two types of HRE fractions having % composition; (i) Y 2 O 3 : 0.18, Tb 4 O 7 : 0.28, Dy 2 CO 2 : 47.07, Er 2 O 3 : 35.03, HO 2 O 3 : 10.11, Yb 2 O 3 : 5.88, Tm 2 O 3 : 1.43 and (ii) Dy 2 O 3 : 6.39, Er 2 O 3 : 49.43, HO 2 O 3 : 10.43, Tm 2 O 3 : 2.7, Y 2 O 3 : 24.08, Yb 2 O 3 : 6.96. PC88A was used to process low Y content concentrate from chloride medium whereas Aliquat336 was found to be suitable in thiocynate medium to treat the concentrate with high Y content. Effects of process variables such as acidity, extractant concentration, total oxide concentration in feed, number of stages, phase ratio, scrubbing agent were investigated for both the systems

  13. Erbium-doped borosilicate glasses containing various amounts of P{sub 2}O{sub 5} and Al{sub 2}O{sub 3}: Influence of the silica content on the structure and thermal, physical, optical and luminescence properties

    Energy Technology Data Exchange (ETDEWEB)

    Bourhis, Kevin [Politecnico di Torino, DISAT, Istituto di Ingegneria e Fisica dei Materiali, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Massera, Jonathan [Department of Electronics and Communications Engineering, Tampere University of Technology, Korkeakoulunkatu 3, FI-33720 Tampere (Finland); BioMediTech, Tampere (Finland); Petit, Laeticia, E-mail: laeticia.petit@nlight.net [Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); nLIGHT Corporation, Sorronrinne 9, FI-08500 Lohja (Finland); Koponen, Joona [nLIGHT Corporation, Sorronrinne 9, FI-08500 Lohja (Finland); Fargues, Alexandre; Cardinal, Thierry [CNRS, Université de Bordeaux, ISM, 351 Cours de la Libération, F-33405 Talence (France); Hupa, Leena; Hupa, Mikko [Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); Dussauze, Marc; Rodriguez, Vincent [CNRS, Université de Bordeaux, ICMCB, 87 Avenue du Dr Schweitzer, F-33608 Pessac (France); Ferraris, Monica [Politecnico di Torino, DISAT, Istituto di Ingegneria e Fisica dei Materiali, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy)

    2015-10-15

    Highlights: • Er{sup 3+} doped borosilicate glasses were processed with different compositions and characterizations. • An increase in the SiO{sub 2} content leads to a silicate-rich environment around the Er{sup 3+} site. • An increase in the SiO{sub 2} content decreases the Er{sup 3+} absorption cross-section at 980 nm. • Glasses with 60 mol% of SiO{sub 2} exhibit a stronger emission intensity at 1530 nm than glasses with x = 50. • Highest 1.5 μm emission intensity was achieved for the Al and P containing glass with 60 mol% of SiO{sub 2}. - Abstract: The influence of the silica content on several properties of Er-doped borosilicate glasses in the presence of various amounts of P{sub 2}O{sub 5} and Al{sub 2}O{sub 3} has been investigated. The introduction of P{sub 2}O{sub 5} and/or Al{sub 2}O{sub 3} are responsible for structural modifications in the glass network through a charge-compensation mechanism related to the formation of negatively-charged PO{sub 4} and AlO{sub 4} groups or through the formation of AlPO{sub 4}-like structural units. In this paper, we show that an increase in the SiO{sub 2} content leads to a silicate-rich environment around the Er{sup 3+} site, resulting in an increased dependence of the Er{sup 3+} ions optical and luminescence properties on the P{sub 2}O{sub 5} and/or Al{sub 2}O{sub 3} concentration. The highest emission intensity at 1.5 μm was achieved for the glass with an equal proportion of P and Al in the glass system with 60 mol% of SiO{sub 2}.

  14. Resonance magnetic x-ray scattering study of erbium

    DEFF Research Database (Denmark)

    Sanyal, M.K.; Gibbs, D.; Bohr, J.

    1994-01-01

    The magnetic phases of erbium have been studied by resonance x-ray-scattering techniques. When the incident x-ray energy is tuned near the L(III) absorption edge, large resonant enhancements of the magnetic scattering are observed above 18 K. We have measured the energy and polarization dependence...... of this magnetic scattering and analyzed it using a simple model based on electric dipole and quadrupole transitions among atomic orbitals. The line shapes can be fitted to a magnetic structure combining both c-axis-modulated and basal-plane components. Below 18 K, we have observed unusual behavior of the magnetic...

  15. All-silica photonic bandgap fibre with zero dispersion and a large mode area at 730 nm

    DEFF Research Database (Denmark)

    Riishede, Jesper; Lægsgaard, Jesper; Broeng, Jes

    2004-01-01

    A theoretical analysis of a photonic bandgap fibre, consisting of a pure silica background with a triangular lattice of Ge-doped high-index rods, is presented. This novel fibre design guides a single, well-confined mode in a core region made from undoped silica. The fibre is found to have positive...... waveguide dispersion, which may be used to shift the zero-dispersion wavelength down to 730 nm, while maintaining an effective mode area of 17 $mu@-m$+2$/. This is an order of magnitude larger than what may be achieved in highly non-linear index-guiding microstructured fibres with comparable zero...

  16. Evanescent field characterisation for a d-shaped optical fibre using scanning near-field optical microscopy

    International Nuclear Information System (INIS)

    Huntington, S.T.; Nugent, K.A.; Roberts, A.; Mulvaney, P.; Lo, K.M.

    1997-01-01

    Scanning near field optical microscopy is used to measure the evanescent filed and mode profile of a Ge-doped D-shaped optical fibre. The structure of the fibre is determined by differential etching followed by an investigation of the resultant topography with an atomic force microscope. This information is then used to theoretically model the expected behaviour of the fibre and it is shown that the theoretically model the expected behaviour of the fibre and it is shown that the theoretical results are in excellent agreement with the experimentally observed fields

  17. HOLLOW FIBRE MEMBRANE

    NARCIS (Netherlands)

    Wessling, Matthias; Stamatialis, Dimitrios; Kopec, K.K.; Dutczak, S.M.

    2011-01-01

    The present invention relates to a process for manufacturing a hollow fibre membrane having a supporting layer and a separating layer, said process comprising: (a)extruding a spinning composition comprising a first polymer and a solvent for the first polymer through an inner annular orifice of a

  18. HOLLOW FIBRE MEMBRANE

    NARCIS (Netherlands)

    Wessling, Matthias; Stamatialis, Dimitrios; Kopec, K.K.; Dutczak, S.M.

    2013-01-01

    The present invention relates to a process for manufacturing a hollow fibre membrane having a supporting layer and a separating layer, said process comprising: (a) extruding a spinning composition comprising a first polymer and a solvent for the first polymer through an inner annular orifice of a

  19. Temperature monitoring of vehicle engine exhaust gases under vibration condition using optical fibre temperature sensor systems

    International Nuclear Information System (INIS)

    Zhao, W Z; Suna, T; Grattana, K T V; Shen, Y H; Wei, C L; Al-Shamma'a, A I

    2006-01-01

    Two optical approaches, comprising and contracting both the fluorescence decay lifetime and the fibre Bragg grating (FBG) methods, were developed and evaluated for temperature monitoring of exhaust gases for use on a vehicle engine. The FBGs used in the system were written into specially designed Bi-Ge co-doped photosensitive fibres, to enable them to sustain high temperatures to over 800 0 C, which is far beyond that of FBGs written into most commercial photosensitive fibres. The sensors were subjected to a range of vibration tests, as a part of an optical exhaust monitoring network under development, and results from the test carried out are reported

  20. Review on dielectric properties of rare earth doped barium titanate

    International Nuclear Information System (INIS)

    Ismail, Fatin Adila; Osman, Rozana Aina Maulat; Idris, Mohd Sobri

    2016-01-01

    Rare earth doped Barium Titanate (BaTiO_3) were studied due to high permittivity, excellent electrical properties and have wide usage in various applications. This paper reviewed on the electrical properties of RE doped BaTiO_3 (RE: Lanthanum (La), Erbium (Er), Samarium (Sm), Neodymium (Nd), Cerium (Ce)), processing method, phase transition occurred and solid solution range for complete study. Most of the RE doped BaTiO_3 downshifted the Curie temperature (T_C). Transition temperature also known as Curie temperature, T_C where the ceramics had a transition from ferroelectric to a paraelectric phase. In this review, the dielectric constant of La-doped BaTiO_3, Er-doped BaTiO_3, Sm-doped BaTiO_3, Nd-doped BaTiO_3 and Ce-doped BaTiO_3 had been proved to increase and the transition temperature or also known as T_C also lowered down to room temperature as for all the RE doped BaTiO_3 except for Er-doped BaTiO_3.

  1. Erbium Salts as Non-Toxic Catalysts Compatible with Alternative Reaction Media

    Directory of Open Access Journals (Sweden)

    Manuela Oliverio

    2018-03-01

    Full Text Available Green catalysts must be non-toxic, easy to manage, able to be recovered and reused, active under alternative reaction conditions and cheap. Erbium salts meet all the previously listed characteristics and today they are emerging as a valuable catalytic solution to a number of organic transformations needing a Lewis acid catalyst in wet conditions or under alternative heating sources. This review aims to summarize the application of erbium salts in green organic transformations, with particular emphasis on their versatility under both homogeneous and heterogeneous conditions. The erbium salts’ role in bifunctional catalysis is also presented.

  2. Optical Fibre Bundle

    CERN Multimedia

    These are sample fibre optic cables which are used for networking. Optical fibers are widely used in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths (data rates) than wire cables. Fibers are used instead of metal wires because signals travel along them with less loss and are also immune to electromagnetic interference. This is useful for somewhere like CERN where magnets with their highly powerful magnetic fields could pose a problem.

  3. FIBER OPTICS: Fibre optics: Forty years later

    Science.gov (United States)

    Dianov, Evgenii M.

    2010-01-01

    This paper presents a brief overview of the state of the art in fibre optics and its main applications: optical fibre communications, fibre lasers and fibre sensors for various physical property measurements. The future of fibre optics and the status of this important area of the modern technology in Russia are discussed.

  4. Analysis of glass fibre sizing

    DEFF Research Database (Denmark)

    Petersen, Helga Nørgaard; Kusano, Yukihiro; Brøndsted, Povl

    2014-01-01

    Glass fibre reinforced polymer composites are widely used for industrial and engineering applications which include construction, aerospace, automotive and wind energy industry. During the manufacturing glass fibres, they are surface-treated with an aqueous solution. This process and the treated...... surfaces are called sizing. The sizing influences the properties of the interface between fibres and a matrix, and subsequently affects mechanical properties of composites. In this work the sizing of commercially available glass fibres was analysed so as to study the composition and chemical structures....... Soxhlet extraction was used to extract components of the sizing from the glass fibres. The glass fibres, their extracts and coated glass plates were analysed by Thermo-Gravimetric Analysis combined with a mass spectrometer (TGA-MS), and Attenuated Total Reflectance Fourier Transform Infrared (ATR...

  5. Sputter etching of polymer fibres

    International Nuclear Information System (INIS)

    Carter, G.; Hill, A.E.; Nobes, M.J.; Jeffries, R.; Simmens, S.C.

    1979-01-01

    Fibres of polyamide, polyester and an aromatic polyamide (Kevlar) have been subjected to Ar + ion bombardment erosion in an ion accelerator or an rf discharge system. In the case of the former two polymers, cones are observed to develop upon the fibre surface and these are associated with etch protection resulting from the presence of particles of titanium dioxide pigment. This effect is absent in the third, unpigmented, fibre. In all cases ripple structures with a habit transverse to the fibre axes and of wavelength of approximately 1000 Angstrom are gradually developed during ion bombardment. It is suggested that this morphology results from an underlying periodicity of the fibre structure either inherent in the fibre structure or induced by the irradiation. (author)

  6. Studies on up-gradation of Erbium from a heavy fraction of rare earths with EHEHPA

    International Nuclear Information System (INIS)

    Singh, D.K.; Anitha, M.; Yadav, K.K.; Kotekar, M.K.; Vijayalakshmi, R.; Singh, H.

    2014-01-01

    Erbium is an important heavy rare earth element, which finds wide applications. Recently, use of Erbium oxide as structural coating material in fusion reactor has stimulated the interest in obtaining Erbium in pure form. The separation of Erbium from other rare earths such as Dy, Ho, Y, Yb, Tm etc is very difficult due to low separation factor owing to their similar chemical properties. Additionally due to very low concentration ( 2 O 3 : 1.09, Dy 2 O 3 : 58.07, Er 2 O 3 : 22.0, Ho 2 O 3 : 13.33, Yb 2 O 3 : 4.74, Tm 2 O 3 :0.67 is obtained during purification of Y by Aliquat 336 from thiocyanate medium. In the present investigation this HRE fraction is taken as the feed material for up-gradation of Er by an acidic extractant namely 2 ethyl hexyl - 2 ethyl hexyl phosphonic acid (EHEHPA)

  7. Generalized rate-equation analysis of excitation exchange between silicon nanoclusters and erbium ions

    International Nuclear Information System (INIS)

    Kenyon, A. J.; Wojdak, M.; Ahmad, I.; Loh, W. H.; Oton, C. J.

    2008-01-01

    We discuss the use of rate equations to analyze the sensitization of erbium luminescence by silicon nanoclusters. In applying the general form of second-order coupled rate-equations to the Si nanocluster-erbium system, we find that the photoluminescence dynamics cannot be described using a simple rate equation model. Both rise and fall times exhibit a stretched exponential behavior, which we propose arises from a combination of a strongly distance-dependent nanocluster-erbium interaction, along with the finite size distribution and indirect band gap of the silicon nanoclusters. Furthermore, the low fraction of erbium ions that can be excited nonresonantly is a result of the small number of ions coupled to nanoclusters

  8. Optical switching and photoluminescence in erbium-implanted vanadium dioxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Herianto, E-mail: mail@heriantolim.com; Stavrias, Nikolas; Johnson, Brett C.; McCallum, Jeffrey C. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Marvel, Robert E.; Haglund, Richard F. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37240 (United States)

    2014-03-07

    Vanadium dioxide (VO{sub 2}) is under intensive consideration for optical switching due to its reversible phase transition, which features a drastic and rapid shift in infrared reflectivity. Classified as an insulator–to–metal transition, the phase transition in VO{sub 2} can be induced thermally, electrically, and optically. When induced optically, the transition can occur on sub-picosecond time scales. It is interesting to dope VO{sub 2} with erbium ions (Er{sup 3+}) and observe their combined properties. The first excited-state luminescence of Er{sup 3+} lies within the wavelength window of minimal transmission-loss in silicon and has been widely utilized for signal amplification and generation in silicon photonics. The incorporation of Er{sup 3+} into VO{sub 2} could therefore result in a novel photonic material capable of simultaneous optical switching and amplification. In this work, we investigate the optical switching and photoluminescence in Er-implanted VO{sub 2} thin films. Thermally driven optical switching is demonstrated in the Er-implanted VO{sub 2} by infrared reflectometry. Photoluminescence is observed in the thin films annealed at ∼800 °C or above. In addition, Raman spectroscopy and a statistical analysis of switching hysteresis are carried out to assess the effects of the ion implantation on the VO{sub 2} thin films. We conclude that Er-implanted VO{sub 2} can function as an optical switch and amplifier, but with reduced switching quality compared to pure VO{sub 2}.

  9. Calcium binding by dietary fibre

    International Nuclear Information System (INIS)

    James, W.P.T.; Branch, W.J.; Southgate, D.A.T.

    1978-01-01

    Dietary fibre from plants low in phytate bound calcium in proportion to its uronic-acid content. This binding by the non-cellulosic fraction of fibre reduces the availability of calcium for small-intestinal absorption, but the colonic microbial digestion of uronic acids liberates the calcium. Thus the ability to maintain calcium balance on high-fibre diets may depend on the adaptive capacity on the colon for calcium. (author)

  10. Advanced Fibre Based Energy Storage

    Science.gov (United States)

    Reid, Daniel Oliver

    New energy storage devices are required to enable future technologies. With the rise of wearable consumer and medical devices, a suitable flexible and wearable means of storing electrical energy is required. Fibre-based devices present a possible method of achieving this aim. Fibres are inherently more flexible than their bulk counterparts, and as such can be employed to form the electrodes of flexible batteries and capacitors. They also present a facile possibility for incorporation into many fabrics and clothes, further boosting their potential for use in wearable devices. Electrically conducting fibres were produced from a dispersion of carbon nanomaterials in a room temperature ionic liquid. Coagulation of this dispersion was achieved through manual injection into aqueous solutions of xanthan gum. The limitations of this method are highlighted by very low ultimate tensile strengths of these fibres, in the order of 3 MPa, with high variation within all of the fibres. Fibres were also produced via scrolling of bi-component films containing poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and poly(vinyl alcohol) (PVA). Chemical treatments were employed to impart water compatibility to these fibres, and their electrochemical, physical and electrical properties were analysed. Fibres were wet spun from two PEDOT:PSS sources, in several fibre diameters. The effect of chemical treatments on the fibres were investigated and compared. Short 5 min treatment times with dimethyl sulfoxide (DMSO) on 20 mum fibres produced from Clevios PH1000 were found to produce the best overall treatment. Up to a six-fold increase in electrical conductivity resulted, reaching 800 S cm-1, with up to 40 % increase in specific capacitance and no loss of mechanical strength (55 F g-1 and 150 MPa recorded). A wet spinning system to produce PEDOT:PSS fibres containing functionalised graphenes and carbon nanotubes, as well as birnessite nanotubes was subsequently developed

  11. Erbium Laser Technology vs Traditional Drilling for Caries Removal: A Systematic Review with Meta-Analysis.

    Science.gov (United States)

    Tao, Siying; Li, Lan; Yuan, He; Tao, Sibei; Cheng, Yiming; He, Libang; Li, Jiyao

    2017-12-01

    The study aimed to assess the efficacy of erbium laser technology compared with traditional drilling for caries removal. A systematic search was conducted through Medline via PubMed, Embase, Cochrane databases, CNKI till December 2016. Randomised controlled trials, quasi-randomized controlled trials, or controlled clinical trials with data comparing the efficacy of erbium laser technology versus traditional drilling for caries removal were included. Fourteen studies were selected in our meta-analysis. Erbium laser technology showed an increased time when removing caries compared with drilling (mean difference: 3.48, 95% confidence interval: 1.90-5.06, P drilling with regard to restoration loss, pulpal vitality, and postoperative sensitivity. Erbium laser technology showed an increased time for cavity preparation compared with traditional drilling. However, erbium laser technology reduced the requirement for local anesthesia. There was no significant difference between erbium laser technology and traditional drilling regarding restoration loss, pulpal vitality, and postoperative sensitivity. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Organo-erbium systems for optical amplification at telecommunications wavelengths.

    Science.gov (United States)

    Ye, H Q; Li, Z; Peng, Y; Wang, C C; Li, T Y; Zheng, Y X; Sapelkin, A; Adamopoulos, G; Hernández, I; Wyatt, P B; Gillin, W P

    2014-04-01

    Modern telecommunications rely on the transmission and manipulation of optical signals. Optical amplification plays a vital part in this technology, as all components in a real telecommunications system produce some loss. The two main issues with present amplifiers, which rely on erbium ions in a glass matrix, are the difficulty in integration onto a single substrate and the need of high pump power densities to produce gain. Here we show a potential organic optical amplifier material that demonstrates population inversion when pumped from above using low-power visible light. This system is integrated into an organic light-emitting diode demonstrating that electrical pumping can be achieved. This opens the possibility of direct electrically driven optical amplifiers and optical circuits. Our results provide an alternative approach to producing low-cost integrated optics that is compatible with existing silicon photonics and a different route to an effective integrated optics technology.

  13. Cerium(terbium, erbium)chloride-choline chloride aqueous systems

    International Nuclear Information System (INIS)

    Gajfutdinova, R.K.; Zhuravlev, E.F.; Bikbaeva, G.G.; Domrachev, V.N.; Vanskova, G.I.

    1985-01-01

    To clarify the effect of rare earth nature on mutual solubility of rare earth salts and amines the solubility of solid phases in the systems, consisting of choline chloride, water and cerium, terbium, erbium chlorides, has been studied. It is established, that solubility isotherms of all the systems, testify to the formation of new solid phases of the composition: Ce(Tb, Er)xCl 3 x2C 5 H 14 ONClx3H 2 O. Individuality of new solid phases is proved by DTA method, the composition is confirmed by chemical analysis and data of PMR spectra, for choline chloride and its complexes with rare earth chlorides of the given composition PMR and IR spectra are studied

  14. Mechanical properties of melt-derived erbium oxide

    International Nuclear Information System (INIS)

    Neuman, A.D.; Blacic, M.J.; Platero, M.; Romero, R.S.; McClellan, K.J.; Petrovic, J.J.

    1998-01-01

    Erbium oxide (Er 2 O 3 ) is a rare earth oxide that is chemically and thermally stable and has a melting point of 2,430 C. There is relatively little information available regarding single crystal growth of erbia or the properties of erbia. In this study, erbia single crystals have been grown in a Xenon Optical Floating Zone Unit (XeOFZ) capable of melting materials at temperatures up to 3,000 C. Erbia was melt synthesized in the XeOFZ unit in a container less fashion, proving for little chance of contamination. Crystals were grown in compressed air and in reducing atmospheres. A recurring problem with melt synthesis of erbia is the appearance of flakes at the edges of the melt zone during growth; these flakes disrupt the growth process. The processing details and an initial survey of the physical properties of erbia single crystals is discussed

  15. Creep properties of discontinuous fibre composites with partly creeping fibres

    International Nuclear Information System (INIS)

    Bilde-Soerensen, J.B.; Lilholt, H.

    1977-05-01

    In a previous report (RISO-M-1810) the creep properties of discontinuous fibre composites with non-creeping fibres were analyzed. In the present report this analysis is extended to include the case of discontinuous composites with partly creeping fibres. It is shown that the creep properties of the composite at a given strain rate, epsilonsub(c), depend on the creep properties of the matrix at a strain rate higher than epsilonsub(c), and on the creep properties of the fibres at epsilonsub(c). The composite creep law is presented in a form which permits a graphical determination of the composite creep curve. This can be constructed on the basis of the matrix and the fibre creep curves by vector operations in a log epsilon vs. log sigma diagram. The matrix contribution to the creep strength can be evaluated by a simple method. (author)

  16. Scintillating-fibre calorimetry

    International Nuclear Information System (INIS)

    Livan, M.; Vercesi, V.; Wigmans, R.

    1995-01-01

    In the past decade, calorimetry based on scintillating plastic fibres as active elements was developed from a conceptual idea to a mature detector technology, which is nowadays widely applied in particle physics experiments. This development and the performance characteristics of representative calorimeters, both for the detection of electromagnetic and hadronic showers, are reviewed. We also discuss new information on shower development processes in dense matter and its application to calorimetric principles that has emerged from some very thorough studies that were performed in the framework of this development. (orig.)

  17. Properties of hemp fibre polymer composites - An optimisation of fibre properties using novel defibration methods and fibre characterisation

    DEFF Research Database (Denmark)

    Thygesen, Anders

    2006-01-01

    Characterization of hemp fibres was carried out with fibres obtained with low handling damage and defibration damage to get an indication of how strong cellulose based fibres that can be produced from hemp. Comparison was made with hemp yarn producedunder traditional conditions where damage...... obtained by steam explosion of hemp fibres prior defibrated with pectin degrading enzymes. The S2 layer in the fibre wall of the hemp fibres consisted of1-4 cellulose rich and lignin poor concentric layers constructed of ca. 100 nm thick lamellae. The microfibril angle showed values in the range 0......-10° for the main part of the S2-layer and 70-90° for the S1-layer. The microfibrils that are mainly parallelwith the fibre axis explain the high fibre stiffness, which in defibrated hemp fibres reached 94 GPa. The defibrated hemp fibres had higher fibre stiffness (88-94 GPa) than hemp yarn (60 GPa), which...

  18. Preparation and properties of thick not intentionally doped GaInP(As)/GaAs layers

    CERN Document Server

    Nohavica, D; Zdansky, K

    1999-01-01

    We report on liquid-phase epitaxial growth of thick layers of GaInP(As), lattice matched to GaAs. Layers with thicknesses up to 10 mu m were prepared in a multi-melt bin, step-cooling, one-phase configuration. Unintentionally doped layers, grown from moderate purity starting materials, show a significant decrease in the residual impurity level when erbium is added to the melt. Fundamental electrical and optical properties of the layers were investigated. (author)

  19. Fibre-optic temperature sensor

    International Nuclear Information System (INIS)

    Zhao Jie; Liu Zhenyuan.

    1993-04-01

    This experiment is a kind of nonfunction fibre-optic temperature sensor. It utilizes high-sensitive bimetallic strip for element of measuring temperature. The changing of bimetallic strip alterates intensity of light through fibre-optic. This equipment is simple in structure, subtle in design, extensive in application, and so on. (author). 4 refs, 6 figs, 1 tab

  20. Current status of natural fibres

    CSIR Research Space (South Africa)

    Anandjiwala, RD

    2006-12-01

    Full Text Available Fiber Selection Conference, 17-19 May 1999, Greenville, SC, USA. 16. Sankari, H.S. 2000. Comparison of bast fibre yield and mechanical fibre properties of hemp (Cannabis sativa L.) cultivars. Industrial Crops and Products (11) 1: 73-84. 17. W...

  1. Tunable and stable single-longitudinal-mode dual-wavelength erbium fiber laser with 1.3 nm mode spacing output

    International Nuclear Information System (INIS)

    Yeh, C H; Shih, F Y; Wang, C H; Chow, C W; Chi, S

    2008-01-01

    In this investigation, we propose and investigate a stable and tunable dual-wavelength erbium-doped fiber (EDF) ring laser with self-injected Fabry-Perot laser diode (FP-LD) scheme. By using an FP-LD incorporated with a tunable bandpass filter (TBF) within the gain cavity, the fiber laser can lase at two single-longitudinal-mode (SLM) wavelengths simultaneously due to the self-injected operation. The proposed dual-wavelength laser has a good performance of the output power and optical side-mode suppression ratio (SMSR). The laser also shows a wide tuning range from 1523.08 to 1562.26 nm. Besides, the output stabilities of the fiber laser are also discussed

  2. Radiation hardening in sol-gel derived Er3+-doped silica glasses

    International Nuclear Information System (INIS)

    Hari Babu, B.; León Pichel, Mónica; Ollier, Nadège; El Hamzaoui, Hicham; Bigot, Laurent; Savelii, Inna; Bouazaoui, Mohamed; Poumellec, Bertrand; Lancry, Matthieu; Ibarra, Angel

    2015-01-01

    The aim of the present paper is to report the effect of radiation on the Er 3+ -doped sol-gel silica glasses. A possible application of these sol-gel glasses could be their use in harsh radiation environments. The sol-gel glasses are fabricated by densification of erbium salt-soaked nanoporous silica xerogels through polymeric sol-gel technique. The radiation-induced attenuation of Er 3+ -doped sol-gel silica is found to increase with erbium content. Electron paramagnetic resonance studies reveal the presence of E′ δ point defects. This happens in the sol-gel aluminum-silica glass after an exposure to γ-rays (kGy) and in sol-gel silica glass after an exposure to electrons (MGy). The concentration levels of these point defects are much lower in γ-ray irradiated sol-gel silica glasses. When the samples are co-doped with Al, the exposure to γ-ray radiation causes a possible reduction of the erbium valence from Er 3+ to Er 2+ ions. This process occurs in association with the formation of aluminum oxygen hole centers and different intrinsic point defects

  3. Parametric study of up-conversion efficiency in Er-doped ceria nanoparticles under 780 nm excitation

    International Nuclear Information System (INIS)

    Shehata, N.; Kandas, I.; Samir, E.; Meehan, K.; Aldacher, M.

    2016-01-01

    This paper presents a new parametric study of the optical up-conversion process in ceria nanoparticles doped with erbium (Er-CeO 2 NPs). Under 780 nm excitation, both the possible transitions that occur between Er 3+ ions and up-conversion rate model simulation are presented. Ceria nanoparticles (CeO 2 NPs) doped with erbium are experimentally synthesized using chemical precipitation technique with post-annealing up to 900 °C with different weight ratios of erbium dopant. We found that the synthesized nanoparticles can emit both green and red emissions under 780 nm laser excitation via two-photon absorption mechanism. Then, the quantum efficiencies of both colored emissions are theoretically investigated with different parameters related to the optical conversion process and the studied material. In addition, this work offer suggested ranges for the optimum values of the studied parameters which could improve the quantum yield efficiency. Einstein coefficients for erbium hosted in ceria are discussed in details using Judd–Ofelt analysis. This promising study could be helpful in improving the up-conversion efficiency of Er-ceria nanoparticles for applications such as bio-imaging and optical-based sensors.

  4. Optical gain at 1.53 {mu}m in Er{sup 3+}-Yb{sup 3+} co-doped porous silicon waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Najar, A. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, BP 80518, 22305 Lannion Cedex (France); Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 El Manar, Tunis (Tunisia)], E-mail: najar.adel@laposte.net; Charrier, J. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, BP 80518, 22305 Lannion Cedex (France); Ajlani, H. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 El Manar, Tunis (Tunisia); Lorrain, N.; Haesaert, S. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, BP 80518, 22305 Lannion Cedex (France); Oueslati, M. [Laboratoire de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 El Manar, Tunis (Tunisia); Haji, L. [Laboratoire d' Optronique UMR 6082-FOTON, Universite de Rennes 1, 6 rue de Kerampont, BP 80518, 22305 Lannion Cedex (France)

    2008-01-15

    Erbium-ytterbium (Er-Yb)-co-doped porous silicon planar waveguides were prepared from P{sup +}-type (1 0 0) oriented silicon wafer. Erbium and ytterbium ions were electrochemically introduced into the porous structure of the waveguide core. The doping profiles of erbium and ytterbium ions were determined by EDX analysis performed on sample cross-section. The mean concentration in the guiding layer is of about 1 x 10{sup 20} cm{sup -3}. The refractive indices were measured from co-doped porous silicon and undoped waveguides after the thermal treatments. The photoluminescence (PL) peak of optically activated erbium ions at 1.53 {mu}m was recorded. The PL enhancement is the result of the energy transfer from the excited state of Yb to the state of Er. Optical losses at 1.55 {mu}m were measured on these waveguides and were of about 2 dB/cm. An internal gain at 1.53 {mu}m of 5.8 dB/cm has been measured with a pump power of 65 mW at 980 nm.

  5. Random distributed feedback fibre lasers

    Energy Technology Data Exchange (ETDEWEB)

    Turitsyn, Sergei K., E-mail: s.k.turitsyn@aston.ac.uk [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Babin, Sergey A. [Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Churkin, Dmitry V. [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Vatnik, Ilya D.; Nikulin, Maxim [Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Podivilov, Evgenii V. [Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation)

    2014-09-10

    The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the

  6. Random distributed feedback fibre lasers

    International Nuclear Information System (INIS)

    Turitsyn, Sergei K.; Babin, Sergey A.; Churkin, Dmitry V.; Vatnik, Ilya D.; Nikulin, Maxim; Podivilov, Evgenii V.

    2014-01-01

    The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the

  7. Determination of pulse energy dependence for skin denaturation from 585nm fibre laser

    Science.gov (United States)

    Mujica-Ascencio, S.; Velazquez-Gonzalez, J. S.; Mujica-Ascencio, C.; Alvarez-Chavez, J. A.

    2014-05-01

    In this paper, simulation and mathematical analysis for the determination of pulse energy from a Q-switched Yb3+-doped fibre laser is required in Port Wine Stain (PWS) treatment. The pulse energy depends on average power, gain, volume, repetition rate and pulse duration. In some treatments such as Selective Photothermolysis (SP), the peak power at the end of the optical fibre and pulse duration can be obtained and modified via a cavity design. For that purpose, a 585nm optical fibre laser full design which considers all of the above besides the average losses through the optical devices proposed for the design and the Ytterbium optical fibre overall gain will be presented.

  8. Microstructured Optical Fibres

    DEFF Research Database (Denmark)

    1999-01-01

    The present invention relates to a new class of optical waveguides, in which waveguiding along one or more core regions is obtained through the application of the Photonic Bandgap (PBG) effect. The invention further relates to optimised two-dimensional lattice structures capable of providing......, which are easy to manufacture. Finally, the present invention relates to a new fabrication technique, which allows easy manufacturing of preforms for photonic crystal fibers with large void filling fractions, as well as it allows a high flexibility in the design of the cladding and core structures....... complete PBGs, which reflects light incident from air or vacuum. Such structures may be used as cladding structures in optical fibres, where light is confined and thereby guided in a hollow core region. In addition, the present invention relates to designs for ultra low-loss PBG waveguiding structures...

  9. Dispersion properties of photonic crystal fibres

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Broeng, Jes; Dridi, Kim

    1998-01-01

    Approximate dispersion and bending properties of all-silica two-dimensional photonic crystal fibres are characterised by the combination of an effective-index model and classical analysis tools for optical fibres. We believe for the first time to have predicted the dispersion properties of photonic...... crystal fibres. The results strongly indicate that these fibres have potential applications as dispersion managing components...

  10. The Influence of Fibre Content on the Performance of Steel Fibre ...

    African Journals Online (AJOL)

    The Influence of Fibre Content on the Performance of Steel Fibre Refractory Concrete. ... Little information is available on the effect of fibre content on refractory performance and in particular resistance to thermal shock. This study has examined the influence of fibre content of stainless steel melt extract fibres on the ...

  11. Fibre Bragg grating and no-core fibre sensors

    CERN Document Server

    Daud, Suzairi

    2018-01-01

    This book focuses on the development and set-up of fibre Bragg grating (FBG) and no-core fibre (NCF) sensors. It discusses the properties of the sensors and modelling of the resulting devices, which include electronic, optoelectronic, photovoltaic, and spintronic devices. In addition to providing detailed explanations of the properties of FBG and NCF sensors, it features a wealth of instructive illustrations and tables, helping to visualize the respective devices’ functions.

  12. Aligned flax fibre/polylactate composites

    DEFF Research Database (Denmark)

    Madsen, Bo; Lilholt, Hans; Thygesen, Anders

    2008-01-01

    The potential of biocomposites in engineering applications is demonstrated by using aligned flax fibre/polylactate composites as a materials model system. The failure stress of flax fibres is measured by tensile testing of single fibres and fibre bundles. For both fibre configurations, it is found...... that failure stress is decreased by increasing the tested fibre volume. Based on two types of flax fibre preforms: carded sliver and unidirectional non-crimp fabric, aligned flax fibre/polylactate composites were fabricated with variable fibre content. The volumetric composition and tensile properties...... of the composite were measured. For composites with a fibre content of 37 % by volume, stiffness is about 20 GPa and failure stress is about 180 MPa. The tensile properties of the composites are analysed with a modified rule of mixtures model, which includes the effect of porosity. The experimental results...

  13. Energy transfer processes in Er-doped crystals

    International Nuclear Information System (INIS)

    Georgescu, Serban; Toma, Octavian

    2005-01-01

    In this paper, the microparameters characteristic to various energy-transfer processes in erbium doped crystals are estimated using the Dexter theory. For all the investigated processes, electric dipole-dipole interaction between donor and acceptor ions is assumed. The spectra appearing in Dexter's expression of the microparameter are simulated as a superposition of Lorentzian lines, knowing the positions of both initial and final Stark levels, and calibrated using the Judd-Ofelt model. This approach can give an estimation of the importance of the energy-transfer processes. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. The Chemical Composition of Grape Fibre

    OpenAIRE

    Jolana Karovičová; Zlatica Kohajdová; Lucia Minarovičová; Veronika Kuchtová

    2015-01-01

    Dietary fibres from cereals are much more used than dietary fibres from fruits; however, dietary fibres from fruits have better quality. In recent years, for economic and environmental reasons, there has been a growing pressure to recover and exploit food wastes. Grape fibre is used to fortify baked goods, because the fibre can lower blood sugar, cut cholesterol and may even prevent colon cancer. Grape pomace is a functional ingredient in bakery goods to increase total phenolic content and di...

  15. Microstructures of erbium modified aluminum-copper alloys

    Energy Technology Data Exchange (ETDEWEB)

    Berghof-Hasselbaecher, Ellen; Schmidt, Gerald; Galetz, Mathias; Schuetze, Michael [DECHEMA-Forschungsinstitut, Frankfurt am Main (Germany); Masset, Patrick J. [Fraunhofer UMSICHT-ATZ Entwicklungszentrum, Sulzbach-Rosenberg (Germany); Zhang, Ligang [Technische Univ. Bergakademie Freiberg (Germany). ZIK Virtuhcon; Liu, Libin; Jin, Zhanpeng [Central South Univ., Changsha, Hunan (China)

    2012-07-01

    Alloying with rare earth metals improves to the mechanical properties and corrosion resistance of aluminium base alloys at high temperatures. The rare earth metal erbium may be used for grain refinement. Within a project of computer-aided alloy development based on the CALPHAD (CALculation of PHAse Diagrams) method various alloys were melted on the Al-rich side of the ternary system Al-Cu-Er under argon atmosphere and their microstructures were characterized in the as-cast state or after long-term isothermal annealing (400 C/960 h) by means of different investigation techniques. As a result, the phases fcc (Al), {tau}{sub 1}-Al{sub 8}Cu{sub 4}Er, {theta}-CuAl{sub 2}, {eta}-CuAl, and Al{sub 3}Er were identified, their compositions and fractions were quantified, and their hardnesses were determined. The experimental obtained microstructures agree very well with the calculated solidification behaviors of the cast alloys. The knowledge gained from this work about the phase compositions and microstructures can also be utilized for the fine optimization of the phase diagram. (orig.)

  16. Hydrogen diffusion along grain boundaries in erbium oxide coatings

    International Nuclear Information System (INIS)

    Mao, Wei; Chikada, Takumi; Suzuki, Akihiro; Terai, Takayuki

    2014-01-01

    Diffusion of interstitial atomic hydrogen in erbium oxide (Er 2 O 3 ) was investigated using density functional theory (DFT) and molecular dynamics (MD) methods. Hydrogen diffusivity in bulk, on (0 0 1) surface, and along Σ13 (4–3–1)/[1 1 1] symmetric tilt grain boundaries (GBs) were evaluated in a temperature range of 673–1073 K, as well as hydrogen diffusion barriers. It was found that H diffusion shows the faster on (0 0 1) surface than along GBs and in bulk. Also, energy barrier of H diffusion in bulk estimated by DFT and MD methods is somewhat higher than that along GBs evaluated in the experiments. This suggests that H diffusion in Er 2 O 3 coatings depends on GBs rather than bulk. In addition, with a correction of GB density, the simulated diffusivity along GBs in MD simulations is in good agreement with the experimental data within one order of magnitude. The discrepancy of H diffusivity between the experiments and the simulations should be reduced by considering H concentration, H diffusion direction, deviations of the initial configuration, vacancy defects, etc

  17. Electroluminescence efficiencies of erbium in silicon-based hosts

    Energy Technology Data Exchange (ETDEWEB)

    Cueff, Sébastien, E-mail: sebastien-cueff@brown.edu, E-mail: christophe.labbe@ensicaen.fr [Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252 CNRS/CEA/Ensicaen/UCBN, Caen 14050 (France); School of Engineering, Brown University, Providence, Rhode Island 02912 (United States); Manel Ramírez, Joan; Berencén, Yonder; Garrido, Blas [MIND-IN2UB, Department Electrònica, Universitat de Barcelona, Martí i Franquès 1, Barcelona 08028 (Spain); Kurvits, Jonathan A.; Zia, Rashid [School of Engineering, Brown University, Providence, Rhode Island 02912 (United States); Department of Physics, Brown University, Providence, Rhode Island 02912 (United States); Rizk, Richard; Labbé, Christophe, E-mail: sebastien-cueff@brown.edu, E-mail: christophe.labbe@ensicaen.fr [Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252 CNRS/CEA/Ensicaen/UCBN, Caen 14050 (France)

    2013-11-04

    We report on room-temperature 1.5 μm electroluminescence from trivalent erbium (Er{sup 3+}) ions embedded in three different CMOS-compatible silicon-based hosts: SiO{sub 2}, Si{sub 3}N{sub 4}, and SiN{sub x}. We show that although the insertion of either nitrogen or excess silicon helps enhance electrical conduction and reduce the onset voltage for electroluminescence, it drastically decreases the external quantum efficiency of Er{sup 3+} ions from 2% in SiO{sub 2} to 0.001% and 0.0004% in SiN{sub x} and Si{sub 3}N{sub 4}, respectively. Furthermore, we present strong evidence that hot carrier injection is significantly more efficient than defect-assisted conduction for the electrical excitation of Er{sup 3+} ions. These results suggest strategies to optimize the engineering of on-chip electrically excited silicon-based nanophotonic light sources.

  18. Highly optimized tunable Er3+-doped single longitudinal mode fiber ring laser, experiment and model

    DEFF Research Database (Denmark)

    Poulsen, Christian; Sejka, Milan

    1993-01-01

    A continuous wave (CW) tunable diode-pumped Er3+-doped fiber ring laser, pumped by diode laser at wavelengths around 1480 nm, is discussed. Wavelength tuning range of 42 nm, maximum slope efficiency of 48% and output power of 14.4 mW have been achieved. Single longitudinal mode lasing...... with a linewidth of 6 kHz has been measured. A fast model of erbium-doped fiber laser was developed and used to optimize output parameters of the laser...

  19. Optical properties of erbium doped antimony based glasses: Promising visible and infrared amplifiers materials

    Czech Academy of Sciences Publication Activity Database

    Hamzaoui, M.; Soltani, M.; Baazouzi, M.; Tioua, B.; Ivanova, Z.G.; Lebullenger, R.; Poulain, M.; Zavadil, Jiří

    2012-01-01

    Roč. 249, č. 11 (2012), s. 2213-2221 ISSN 0370-1972 R&D Projects: GA ČR GAP106/12/2384 Institutional support: RVO:67985882 Keywords : Glasses * Rare earths * Photoluminescence Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.489, year: 2012

  20. Room Temperature Erbium-Doped Yttrium Vanadate (Er:YVO4) Laser and Amplifier

    Science.gov (United States)

    2016-09-01

    10%. We maintained the LDM pump pulse duration at 5 ms, which is much longer than the Er3+ upper laser level (4I13/2) lifetime in YVO4 at RT (3 ms...of 2 ms ranging from 4 to 131 W was used to invert the gain medium. At 1.8 ms into the pump pulse, the 1603-nm seed was turned on for 500 µs. As

  1. Optical, mechanical and fractographic response of transparent alumina ceramics on erbium doping

    Czech Academy of Sciences Publication Activity Database

    Drdlík, D.; Drdlíková, K.; Hadraba, Hynek; Máca, K.

    2017-01-01

    Roč. 37, č. 14 (2017), s. 4265-4270 ISSN 0955-2219 R&D Projects: GA MŠk(CZ) LQ1601; GA ČR(CZ) GA15-06390S Institutional support: RVO:68081723 Keywords : Alumina * Erbia * Fractography * Hardness * Transparency Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 3.411, year: 2016

  2. Erbium and Al2O3 nanocrystals-doped silica optical fibers

    Czech Academy of Sciences Publication Activity Database

    Kašík, Ivan; Podrazký, Ondřej; Mrázek, Jan; Cajzl, Jakub; Aubrecht, Ivo; Proboštová, Jana; Peterka, Pavel; Honzátko, Pavel; Dhar, A.

    2014-01-01

    Roč. 62, č. 4 (2014), s. 641-646 ISSN 0239-7528 Grant - others:GA AV ČR(CZ) M100761202 Institutional support: RVO:67985882 Keywords : optical fibers * nanocrystals * luminescence Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.914, year: 2014

  3. Dispersion and Nonlinearity Characterization of a Mode-Locked Erbium-Doped Fiber Laser

    National Research Council Canada - National Science Library

    Louthain, James

    2001-01-01

    .... These chirped Bragg gratings served as one of the mirrors in the linear fiber laser cavity. Finally, we measured the nonlinearity of five different muhiple quantum well saturable absorbers using a z-scan technique...

  4. Spectroscopic Properties of Erbium Ions Doped in Bismuth Boro-Silicate Glasses

    Science.gov (United States)

    Bhardwaj, Sunil; Shukla, Rajni; Sanghi, Sujata; Agarwal, Ashish; Pal, Inder

    Glasses with composition 20B2O3.(79.5-x)Bi2O3.xSiO2 (10 ≤ x ≤ 40) containing 0.5mol% of Er3+ ions were prepared by melt-quench technique. Optical absorption and fluorescence spectra were recorded at room temperature for all glass samples. Based on the Judd-Offelt theory, spectroscopic properties of Er3+ ions are discussed by changing the host glass compositions. The intensity parameters Ω2, Ω4, and Ω6 are determined by applying least square analysis method. The variation of Ω2 and Ω6 with Bi2O3 content has been attributed to changes in the asymmetry of the ligand field at the rare earth ion site and to the changes in the rare earth oxygen (RE-O) covalency. The variation of Ω4 with Bi2O3 content has been attributed to rigidity of the samples. Using these intensity parameters various radiative properties like spontaneous emission probability, branching ratio, radiative life time and stimulated emission cross-section of various emission lines have been evaluated. An intense green luminescence bands with maximum around 516 nm and 536 nm are assigned to the 2H11/2→ 4I15/2 and 4S3/2→ 4I15/2 transitions respectively has been obtained.

  5. High gain L-band erbium-doped fiber amplifier with two-stage ...

    Indian Academy of Sciences (India)

    One of the key technologies to increase the bandwidth of optical communication systems is to expand ... plexing (WDM) transmission system is very attractive because the system capacity can be doubled by placing .... an important role in the development of practical L-band EDFA from the perspective of economical usage ...

  6. Fundamental design of a distributed erbium-doped fiber amplifier for long-distance transmission

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Bjarklev, Anders Overgaard; Povlsen, Jørn Hedegaard

    1992-01-01

    . Designs based on a bidirectional pumping scheme are evaluated, taking nonlinearities into account. The optimum value of the numerical aperture will be evaluated for cutoff wavelengths where the propagating pump power is single moded. For distances between each pumping station in the region between 10...

  7. Effect of γ-ray irradiation on optical properties of erbium doped bismuth-tellurite glasses

    Science.gov (United States)

    Keshavamurthy, K.; Eraiah, B.

    2018-05-01

    Heavy metal oxide contained glasses are very promising candidates in shielding and photonic materials. In this paper, we studied the effect of γ-ray irradiation on optical properties of Er2O3-Bi2O3-TeO2 glasses through UV-Visible spectrophotometer. After γ-ray exposure, the optical band gap decreases and Urbach energy increases, which is due to creation of defects within the glass network as a result increases the number of non-bridging oxygens.

  8. Direct imaging of optical interference in erbium-doped Al2O3 waveguides

    NARCIS (Netherlands)

    Hoven, van den G.N.; Polman, A.; Dam, van C.; Uffelen, van J.W.M.; Smit, M.K.

    1996-01-01

    Interference of 1.48-mu m light in multimode interference waveguides is made visible by imaging green and infrared upconversion luminescence from Er3+ ions dispersed in the waveguide. A two-dimensional mode density image can be derived from the data and agrees well with mode calculations for this

  9. Suppression of dynamic cross saturation in cascades of overpumped erbium-doped fiber amplifiers

    Czech Academy of Sciences Publication Activity Database

    Karásek, Miroslav; Willems, F. W.

    1998-01-01

    Roč. 10, č. 7 (1998), s. 1036-1038 ISSN 0162-8828 Grant - others:EU COST(XE) OC 241.10 Keywords : optical communication * amplifiers Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.417, year: 1998

  10. Modeling of photonic Crystal Fibres

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Broeng, Jes; Barkou, Stig Eigil

    1999-01-01

    Diferent theoretical models for analysis of photonic crystal fibres are reviewed and compaired. The methods span from simple scalar approaches to full-vectorial models using different mode-field decompositions. The specific advantages of the methods are evaluated.......Diferent theoretical models for analysis of photonic crystal fibres are reviewed and compaired. The methods span from simple scalar approaches to full-vectorial models using different mode-field decompositions. The specific advantages of the methods are evaluated....

  11. Effects of vacuum processing erbium dideuteride/ditritide films deposited on chromium underlays on copper substrates

    International Nuclear Information System (INIS)

    Provo, J.L.

    1978-01-01

    Thin films of erbium dideuteride/ditritide were experimentally produced on chromium underlays deposited on copper substrates. The chromium underlay is required to prevent erbium occluder/copper substrate alloying which inhibits hydriding. Data taken has shown that vacuum processing affects the erbium/chromium/copper interaction. With an in situ process in which underlay/occluder films are vacuum deposited onto copper substrates and hydrided with no air exposure between these steps, data indicates a minimum of 1500A of chromium is required for optimum hydriding. If films are vacuum deposited as above and air-exposed before hydriding, a minimum of 3000A of chromium was shown to be required for equivalent hydriding. Data suggests that the activation step (600 0 C for 1 hour) required for hydriding the film of the second type is responsible for the difference observed. Such underlay thickness parameters are important, with regard to heat transfer considerations in thin hydride targets used for neutron generation

  12. Sensitization of erbium in silicon-rich silica : the effect of annealing temperature and hydrogen passivation

    International Nuclear Information System (INIS)

    Wilkinson, A.R.; Forcales, M.; Elliman, R.G.

    2005-01-01

    This paper reports on the effect of annealing temperature and hydrogen passivation on the excitation cross-section and photoluminescence of erbium in silicon-rich silica. Samples were prepared by co-implantation of Si and Er into SiO 2 followed by a single thermal anneal at temperatures ranging from 800 to 1100 degrees C, and with or without hydrogen passivation performed at 500 degrees C. Using time-resolved photoluminescence, the effective erbium excitation cross-section is shown to increase by a factor 3, while the number of optically active erbium ions decreases by a factor of 4 with increasing annealing temperature. Hydrogen passivation is shown to increase the luminescence intensity and to shorten the luminescence lifetime at 1.54 μm only in the presence of Si nanocrystals. The implications fo these results for realizing a silicon-based optical amplifier are also discussed. (author). 19 refs., 3 figs

  13. Cladding-pumped 70-kW-peak-power 2-ns-pulse Er-doped fiber amplifier

    Science.gov (United States)

    Khudyakov, M. M.; Bubnov, M. M.; Senatorov, A. K.; Lipatov, D. S.; Guryanov, A. N.; Rybaltovsky, A. A.; Butov, O. V.; Kotov, L. V.; Likhachev, M. E.

    2018-02-01

    An all-fiber pulsed erbium laser with pulse width of 2.4 ns working in a MOPA configuration has been created. Cladding pumped double clad erbium doped large mode area fiber was used in the final stage amplifier. Peculiarity of the current work is utilization of custom-made multimode diode wavelength stabilized at 981+/-0.5 nm - wavelength of maximum absorption by Er ions. It allowed us to shorten Er-doped fiber down to 1.7 m and keep a reasonably high pump-to signal conversion efficiency of 8.4%. The record output peak power for all-fiber amplifiers of 84 kW was achieved within 1555.9+/-0.15 nm spectral range.

  14. The Chemical Composition of Grape Fibre

    Directory of Open Access Journals (Sweden)

    Jolana Karovičová

    2015-05-01

    Full Text Available Dietary fibres from cereals are much more used than dietary fibres from fruits; however, dietary fibres from fruits have better quality. In recent years, for economic and environmental reasons, there has been a growing pressure to recover and exploit food wastes. Grape fibre is used to fortify baked goods, because the fibre can lower blood sugar, cut cholesterol and may even prevent colon cancer. Grape pomace is a functional ingredient in bakery goods to increase total phenolic content and dietary fibre in nourishment. The aim of this study was to determine the chemical composition of commercial fibres, obtained from different Grape sources concerning their chemical properties such as moisture, ash, fat, protein, total dietary fibre. The chemical composition of Grape fibre is known to vary depending on the Grape cultivar, growth climates, and processing conditions. The obliged characteristics of the fibre product are: total dietary fibre content above 50%, moisture lower than 9%, low content of lipids, a low energy value and neutral flavour and taste. Grape pomace represents a rich source of various high-value products such as ethanol, tartrates and malates, citric acid, Grape seed oil, hydrocolloids and dietary fibre. Used commercial Grape fibres have as a main characteristic, the high content of total dietary fibre. Amount of total dietary fibre depends on the variety of Grapes. Total dietary fibre content (TDF in our samples of Grape fibre varied from 56.8% to 83.6%. There were also determined low contents of moisture (below 9%. In the samples of Grape fibre were determined higher amount of protein (8.6 - 10.8%, mineral (1.3 - 3.8% and fat (2.8 - 8.6%. This fact opens the possibility of using both initial by-products as ingredients in the food industry, due to the effects associated with the high total dietary fibre content.

  15. Polymorphism of myofibrillar proteins of rabbit skeletal-muscle fibres. An electrophoretic study of single fibres.

    OpenAIRE

    Salviati, G; Betto, R; Danieli Betto, D

    1982-01-01

    Rabbit predominantly fast-twitch-fibre and predominantly slow-twitch-fibre skeletal muscles of the hind limbs, the psoas, the diaphragm and the masseter muscles were fibre-typed by one-dimensional polyacrylamide-gel electrophoresis of the myofibrillar proteins of chemically skinned single fibres. Investigation of the distribution of fast-twitch-fibre and slow-twitch-fibre isoforms of myosin light chains and the type of myosin heavy chains, based on peptide 'maps' published in Cleveland. Fisch...

  16. Experimental and thermodynamic study of the erbium-oxygen-zirconium and gadolinium-oxygen-zirconium systems

    International Nuclear Information System (INIS)

    Jourdan, J.

    2009-11-01

    This work is a contribution to the development of innovative concepts for fuel cladding in pressurized water nuclear reactors. This concept implies the insertion of rare earth (erbium and gadolinium) in the zirconium fuel cladding. The determination of phase equilibria in the systems is essential prior to the implementation of such a promising solution. This study consisted in an experimental determination of the erbium-zirconium phase diagram. For this, we used many different techniques in order to obtain diagram data such as solubility limits, solidus, liquidus or invariant temperatures. These data allowed us to present a new diagram, very different from the previous one available in the literature. We also assessed the diagram using the CALPHAD approach. In the gadolinium-zirconium system, we determined experimentally the solubility limits. Those limits had never been determined before, and the values we obtained showed a very good agreement with the experimental and assessed versions of the diagram. Because these alloys are subjected to oxygen diffusion throughout their life, we focused our attention on the erbium-oxygen-zirconium and gadolinium-oxygen-zirconium systems. The first system has been investigated experimentally. The alloys fabrication has been performed using powder metallurgy. In order to obtain pure raw materials, we fabricated powder from erbium and zirconium bulk metals using hydrogen absorption/desorption. The characterisation of the ternary pellets allowed the determination of two ternary isothermal sections at 800 and 1100 C. For the gadolinium-oxygen-zirconium system, we calculated the phase equilibria at temperatures ranging from 800 to 1100 C, using a homemade database compiled from literature assessments of the oxygen-zirconium, gadolinium-zirconium and gadolinia-zirconia systems. Finally, we determined the mechanical properties, in connexion with the microstructure, of industrial quality alloys in order to identify the influence of

  17. Ternary systems, consist of erbium nitrates, water and nitrates of pyridines, quinolines

    International Nuclear Information System (INIS)

    Starikova, L.I.; Zhuravlev, E.F.; Khalfina, L.R.

    1979-01-01

    At 25 and 50 deg C investigated is solubility of solid phases in ternary water salt systems: erbium nitrate-pyridine nitrate-water; erbium nitrate-quinoline nitrate-water. Formation of congruently soluble compounds of the Er(NO 3 ) 3 x2C 5 H 5 NxHNO 3 , Er(NO 3 ) 3 x2C 9 H 7 NxHNO 3 x4H 2 O composition is established. X-ray phase and thermogravimetric analyses have been carried out

  18. Optical fibre luminescence sensor for real-time LDR brachytherapy dosimetry

    Science.gov (United States)

    Woulfe, P.; O'Keeffe, S.; Sullivan, F. J.

    2018-02-01

    An optical fibre sensor for monitoring low dose radiation is presented. The sensor is based on a scintillation material embedded within the optical fibre core, which emits visible light when exposed to low level ionising radiation. The incident level of ionising radiation can be determined by analysing the optical emission. An optical fibre sensor is developed, based on radioluminescence whereby radiation sensitive scintillation material, terbium doped gadolinium oxysulphide (Gd2O2S:Tb), is embedded in a cavity of 700μm of a 1mm plastic optical fibre. The sensor is designed for in-vivo monitoring of the radiation dose during radio-active seed implantation for low dose rate (LDR) brachytherapy, in prostate cancer treatment, providing radiation oncologists with real-time information of the radiation dose to the target area and/or nearby organs at risk (OARs). The radiation from the brachytherapy seeds causes emission of visible light from the scintillation material through the process of radioluminescence, which penetrates the fibre, propagating along the optical fibre for remote detection using a multi-pixel photon counter. The sensor demonstrates a high sensitivity to 0.397mCi of Iodine125, the radioactive source most commonly used in brachytherapy for treating prostate cancer.

  19. Process monitoring of fibre reinforced composites using optical fibre sensors

    Energy Technology Data Exchange (ETDEWEB)

    Fernando, G.F.; Degamber, B.

    2006-04-15

    The deployment of optical fibre based sensor systems for process monitoring of advanced fibre reinforced organic matrix composites is reviewed. The focus is on thermosetting resins and the various optical and spectroscopy-based techniques that can be used to monitor the processing of these materials. Following brief consideration of the manufacturing methods commonly used in the production of thermoset based composites, a discussion is presented on sensor systems that can be used to facilitate real-time chemical process monitoring. Although the focus is on thermosets, the techniques described can be adapted for chemical monitoring of organic species in general. (author)

  20. Structural, optical and photo thermal properties of Er3+:Y2O3 doped PMMA nanocomposite

    Science.gov (United States)

    Tabanli, Sevcan; Eryurek, Gonul

    2018-02-01

    Thermal decomposition technique was employed to synthesize of phosphors of yttria (Y2O3) doped with erbium (Er3+) ions. After the synthesized procedure, the nano-sized crystalline powders were annealed at 800oC for 24 h. Annealed powders were embedded in poly(methyl methacrylate) (PMMA) by free radical polymerization to fabricate nanocomposite polymer materials. The crystalline structure of the powder and doped PMMA nanocomposite samples were determined using X-ray diffraction technique. Scherrer's equation and the FW1/5/4/5M method were used to determine average crystalline size and grain size distributions, respectively. The spectroscopic properties of the powders and doped PMMA nanocomposites were studied by measuring the upconversion emission spectra under near-infrared laser excitation at room temperature. The laser-induced photo thermal behaviors of Er3+:Y2O3 nano-powders and doped PMMA nanocomposite were investigated using the fluorescence intensity ratio (FIR) technique.

  1. Suppression of concentration quenching of Er-related luminescence in Er-doped GaN

    International Nuclear Information System (INIS)

    Chen Shaoqiang; Tomita, Shigeo; Kudo, Hiroshi; Akimoto, Katsuhiro; Dierre, Benjamin; Lee, Woong; Sekiguchi, Takashi

    2010-01-01

    Erbium-doped GaN with different doping concentrations were grown by ammonia-source molecular beam epitaxy. The intra-4f-shell transitions related green luminescence were observed by both photoluminescence (PL) and cathodoluminescence (CL) measurements. It was found that concentration quenching of Er-related luminescence was observed in PL measurements while not in CL measurements. The different excitation and relaxation processes are suggested as the cause of the concentration quenching characteristics between PL and CL. The strong Er-related CL intensity in highly doped GaN demonstrates that high energy excitation is a promising approach to suppress the concentration quenching in Er-doped GaN.

  2. Carbon fibre material for tomorrow

    International Nuclear Information System (INIS)

    Kartini Noorsal; Mohd Ariff Baharom

    2010-01-01

    As science and technology continue to cross boundaries of known practices, materials and manufacturing techniques and into the frontiers of new materials, environment and applications, the opportunities for research in materials in general will inevitably increase. The unique properties of carbon fibre which combines low weight and high stiffness, makes it in ever greater demand as substitutes for traditional materials. This is due to the rising costs of raw materials and energy and the necessity to reduce carbon dioxide emission. The carbon fibres produced are particularly of high standard in terms of quality and processing characteristics especially when it is designed in structural components in the aerospace and defence industries. This results in a well structured organisation in producing the fibre starting from its raw material to the final composite products. In achieving this effort, research and communication of the progress takes a fundamental role. (author)

  3. LHCb Upgrade: Scintillating Fibre Tracker

    International Nuclear Information System (INIS)

    Tobin, Mark

    2016-01-01

    The LHCb detector will be upgraded during the Long Shutdown 2 (LS2) of the LHC in order to cope with higher instantaneous luminosities and to read out the data at 40 MHz using a trigger-less read-out system. All front-end electronics will be replaced and several sub-detectors must be redesigned to cope with higher occupancy. The current tracking detectors downstream of the LHCb dipole magnet will be replaced by the Scintillating Fibre (SciFi) Tracker. The SciFi Tracker will use scintillating fibres read out by Silicon Photomultipliers (SiPMs). State-of-the-art multi-channel SiPM arrays are being developed to read out the fibres and a custom ASIC will be used to digitise the signals from the SiPMs. The evolution of the design since the Technical Design Report in 2014 and the latest R & D results are presented.

  4. EFFECTS OF POLYTHENE FIBRES ON SELECTED PROPERTIES ...

    African Journals Online (AJOL)

    eobe

    ABSTRACT. The aim of this study is to explore the possibility of using polythene fibres to increase the strength of sandcrete ... Polythene fibres were got from shredded sachet water bags. .... degradable waste is more of a problem than the bio-.

  5. Airplane dopes and doping

    Science.gov (United States)

    Smith, W H

    1919-01-01

    Cellulose acetate and cellulose nitrate are the important constituents of airplane dopes in use at the present time, but planes were treated with other materials in the experimental stages of flying. The above compounds belong to the class of colloids and are of value because they produce a shrinking action on the fabric when drying out of solution, rendering it drum tight. Other colloids possessing the same property have been proposed and tried. In the first stages of the development of dope, however, shrinkage was not considered. The fabric was treated merely to render it waterproof. The first airplanes constructed were covered with cotton fabric stretched as tightly as possible over the winds, fuselage, etc., and flying was possible only in fine weather. The necessity of an airplane which would fly under all weather conditions at once became apparent. Then followed experiments with rubberized fabrics, fabrics treated with glue rendered insoluble by formaldehyde or bichromate, fabrics treated with drying and nondrying oils, shellac, casein, etc. It was found that fabrics treated as above lost their tension in damp weather, and the oil from the motor penetrated the proofing material and weakened the fabric. For the most part the film of material lacked durability. Cellulose nitrate lacquers, however were found to be more satisfactory under varying weather conditions, added less weight to the planes, and were easily applied. On the other hand, they were highly inflammable, and oil from the motor penetrated the film of cellulose nitrate, causing the tension of the fabric to be relaxed.

  6. Fibre Optic Communication Key Devices

    CERN Document Server

    Grote, Norbert

    2012-01-01

    The book gives an in-depth description of the key devices of current and next generation fibre optic communication networks. In particular, the book covers devices such as semiconductor lasers, optical amplifiers, modulators, wavelength filters, and detectors but the relevant properties of optical fibres as well. The presentations include the physical principles underlying the various devices, the technologies used for the realization of the different devices, typical performance characteristics and limitations, and development trends towards more advanced components are also illustrated. Thus the scope of the book spans relevant principles, state-of-the-art implementations, the status of current research and expected future components.

  7. Photonic crystal fibres and effective index approaches

    DEFF Research Database (Denmark)

    Riishede, Jesper; Libori, Stig E. Barkou; Bjarklev, Anders Overgaard

    2001-01-01

    Photonic crystal fibres are investigated with an effective index approach. The effective index of both core and cladding is found to be wavelength dependent. Accurate modelling must respect the rich topology of these fibres.......Photonic crystal fibres are investigated with an effective index approach. The effective index of both core and cladding is found to be wavelength dependent. Accurate modelling must respect the rich topology of these fibres....

  8. Fibre optic networks for safeguards applications

    International Nuclear Information System (INIS)

    Smith, B.G.R.; Chare, P.; Barrier, A.

    1991-01-01

    The Euratom Safeguards Directorate has recently installed a fibre optic network in a new large scale nuclear facility in the European Communities. The selection, installation and commissioning of the fibre optic network is discussed from the viewpoint of network topology, physical testing, trouble shooting and authentication. The future use of fibre optic networks for safeguards applications is discussed

  9. Continuous jute fibre reinforced laminated paper composite

    Indian Academy of Sciences (India)

    Jute fibre; laminated paper composite; plastic bag pollution. Abstract. Plastic bags create a serious environmental problem. The proposed jute fibre reinforced laminated paper composite and reinforcement-fibre free paper laminate may help to combat the war against this pollutant to certain extent. The paper laminate ...

  10. Stress concentrations in an impregnated fibre bundle with random fibre packing

    OpenAIRE

    Swolfs, Y.; Gorbatikh, L.; Romanov, V.; Orlova, S.; Lomov, S. V.; Verpoest, I.

    2013-01-01

    The stress redistribution after a single fibre break is a fundamental issue in longitudinal strength models for unidirectional composites. Current models assume hexagonal or square fibre packings. In the present work, random fibre packings were modelled using 3D finite element analysis and compared to ordered fibre packings. Significant differences in the stress redistribution are found. Compared to square and hexagonal packings, random fibre packings result in smaller stress concentration fa...

  11. Mechanical processing of bast fibres: The occurrence of damage and its effect on fibre structure

    DEFF Research Database (Denmark)

    Hänninen, Tuomas; Thygesen, Anders; Mehmood, Shahid

    2012-01-01

    Currently, separation processes used for natural fibres for composite reinforcing textiles cause a significant amount of damage to the fibres. Microscopic analysis showed that industrially processed flax (Linum usitassimium L.) fibres contained significantly more defects than green or retted ones...... to heterogeneous reactivity. Analogous findings were observed in hemp (Cannabis sativa L.) fibre damaged in the laboratory under controlled conditions, emphasising the need to develop extraction and separation processes that minimise mechanical damage to the fibres....

  12. Linearly polarized intracavity passive Q-switched Yb-doped ...

    Indian Academy of Sciences (India)

    2014-02-14

    Feb 14, 2014 ... ytterbium-doped photonic crystal fibre laser with a Cr4+:YAG crystal ... average output power of 9.4 W with pulse duration of 64 ns and ... applications of nonlinear frequency shifting like frequency doubling and optical paramet-.

  13. Flow diagnostics using fibre optics

    Indian Academy of Sciences (India)

    hypersonic vehicle with a 2-component fibre-optic strain-gauge balance. ... ment suffers a fall in accuracy to uncomfortable levels (more than 5%) and the measurement .... 15 kW motor with an associated thyristor speed-control system.

  14. 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...

  15. Connections on discrete fibre bundles

    International Nuclear Information System (INIS)

    Manton, N.S.; Cambridge Univ.

    1987-01-01

    A new approach to gauge fields on a discrete space-time is proposed, in which the fundamental object is a discrete version of a principal fibre bundle. If the bundle is twisted, the gauge fields are topologically non-trivial automatically. (orig.)

  16. Cool application for Optical Fibres

    CERN Multimedia

    2001-01-01

    In a new first for CERN, optical fibres have been put on test to measure very low temperatures. If these tests prove successful, this new technology could lead to important cost-saving changes in the way the temperatures of superconducting magnets are measured. There was excitement in the air last March when the team led by Walter Scandale and Luc Thévenaz tested very low temperature measurement using optical fibres. This spring in CERN's Cryogenics lab an idea was put to the test as a new kind of low-temperature thermometry using optical fibres was tested down to 2 Kelvin (around 300 degrees below room temperature), and the first results are looking good. Optical fibres are well known for their ability to carry large amounts of data around the world, but it is less well known that they can be used for measuring temperatures. The intuition that they might be able to measure very low temperatures - such as those of the LHC magnets - came to the attention of CERN's Walter Scandale at the Optical Fi...

  17. Laser–fibre vibrometry at 1550 nm

    International Nuclear Information System (INIS)

    Waz, A T; Kaczmarek, P R; Abramski, K M

    2009-01-01

    This paper presents new solutions for laser vibrometry, which are based on fibre vibrometry in the third telecommunication window. The scattered laser beam from a vibrating object is guided by a fibre collimator and coherently detected through heterodyning it with an acousto-optical frequency-shifted reference beam. The concept of measuring vibration parameters from many points of the vibrating object has been inspired by wavelength division multiplexing (WDM) in fibre telecommunications. The N-independent WDM separated 15XX nm fibre-coupled laser diodes (used for optical fibre telecommunications) form a system of sources for multipoint vibration measurement according to the rule 'one wavelength–one point'

  18. Fibre optic cable in the nuclear industry

    International Nuclear Information System (INIS)

    Roberts, Berwyn

    1987-01-01

    The uses of optical fibre cables to transmit light signals include medical applications and telecommunications. In the nuclear industry the applications include process control and monitoring, conventional datacoms, security fencing and sensors. Time division multiplexing is described and currently available fibre optic multipexers are listed and explained. Single and multimode fibres are mentioned. Fibre optics are also used in cryogenics, to monitor the integrity of the storage vessels for cryogenic liquids. The uses of fibre optics at Hartlepool, Heysham I and Torness are mentioned in particular. (UK)

  19. Coupling of erbium dopants to yttrium orthosilicate photonic crystal cavities for on-chip optical quantum memories

    Energy Technology Data Exchange (ETDEWEB)

    Miyazono, Evan; Zhong, Tian; Craiciu, Ioana; Kindem, Jonathan M.; Faraon, Andrei, E-mail: faraon@caltech.edu [T. J. Watson Laboratory of Applied Physics, California Institute of Technology, 1200 E California Blvd, Pasadena, California 91125 (United States)

    2016-01-04

    Erbium dopants in crystals exhibit highly coherent optical transitions well suited for solid-state optical quantum memories operating in the telecom band. Here, we demonstrate coupling of erbium dopant ions in yttrium orthosilicate to a photonic crystal cavity fabricated directly in the host crystal using focused ion beam milling. The coupling leads to reduction of the photoluminescence lifetime and enhancement of the optical depth in microns-long devices, which will enable on-chip quantum memories.

  20. Plant fibre composites - porosity and volumetric interaction

    DEFF Research Database (Denmark)

    Madsen, Bo; Thygesen, Anders; Lilholt, Hans

    2007-01-01

    the combination of a high fibre volume fraction, a low porosity and a high composite density is optimal. Experimental data from the literature on volumetric composition and density of four types of plant fibre composites are used to validate the model. It is demonstrated that the model provides a concept......Plant fibre composites contain typically a relative large amount of porosity, which considerably influences properties and performance of the composites. The large porosity must be integrated in the conversion of weight fractions into volume fractions of the fibre and matrix parts. A model...... is presented to predict the porosity as a function of the fibre weight fractions, and to calculate the related fibre and matrix volume fractions, as well as the density of the composite. The model predicts two cases of composite volumetric interaction separated by a transition fibre weight fraction, at which...

  1. Optical fibre laser velocimetry: a review

    International Nuclear Information System (INIS)

    Charrett, Thomas O H; James, Stephen W; Tatam, Ralph P

    2012-01-01

    The applications of optical fibre technology to laser velocimetry are diverse and often critical to their successful implementation, particularly in harsh environments. Applications range from the use of optical fibres for beam delivery and scattered light collection, aiding the miniaturization of instrument probes, to the use of imaging fibre bundles for imaging the flow field in planar velocimetry systems. Optical fibre techniques have also been used in signal processing, for example fibre frequency shifters, and optical fibre devices such as amplifiers and lasers have been exploited. This paper will review the use of optical fibres in point-wise laser velocimetry techniques such as laser Doppler velocimetry and laser transit anemometry, as well as in planar measurement techniques such as particle imaging velocimetry and planar Doppler velocimetry. (topical review)

  2. Mid-infrared supercontinuum generation to 12.5μm in large NA chalcogenide step-index fibres pumped at 4.5μm

    DEFF Research Database (Denmark)

    Kubat, Irnis; Agger, Christian; Møller, Uffe Visbech

    2014-01-01

    We present numerical modeling of mid-infrared (MIR) supercontinuum generation (SCG) in dispersion-optimized chalcogenide (CHALC) step-index fibres (SIFs) with exceptionally high numerical aperture (NA) around one, pumped with mode-locked praseodymium-doped (Pr3+) chalcogenide fibre lasers. The 4...... for the highest NA considered but required pumping at 4.7kW as well as up to 3m of fibre to compensate for the lower nonlinearities. The amount of power converted into the 8-10 μm band was 7.5 and 8.8mW for the 8 and 10μm fibres, respectively. For the 20μm core fibres up to 46mW was converted....

  3. Optical Properties of Erbium Zinc Tellurite Glass System

    Directory of Open Access Journals (Sweden)

    Sidek Hj. Abdul Aziz

    2015-01-01

    Full Text Available Er3+-doped tellurite glasses with molar compositions of xEr2O3-20ZnO-(80-xTeO2 (x=0, 1, 2, 3, and 4 mole% (EZT have been successfully synthesized by the melt-quenching method. Density and molar volume have been measured. UV-VIS absorption spectra in the wavelength range of 400–800 nm at room temperature has been measured. The band gap for every composition has been calculated. Photoluminescence spectroscopy in the wavelength range of 400–650 nm and at room temperature has been evaluated.

  4. A high-resolution detector based on liquid-core scintillating fibres with readout via an electron-bombarded charge-coupled device

    International Nuclear Information System (INIS)

    Cianfarani, C.; Duane, A.; Fabre, J.P.; Frenkel, A.; Golovkin, S.V.; Gorin, A.M.; Harrison, K.; Kozarenko, E.N.; Kushnirenko, A.E.; Ladygin, E.A.; Martellotti, G.; Medvedkov, A.M.; Nass, P.A.; Obudovski, V.P.; Penso, G.; Petukhov, Yu.P.; Siegmund, W.P.; Tyukov, V.E.; Vasilchenko, V.G.

    1994-01-01

    This paper is a presentation of results from tests in a 5 GeV/c hadron beam of detectors based on liquid-core scintillating fibres, each fibre consisting of a glass capillary filled with organic liquid scintillator. Fibre readout was performed via an Electron-Bombarded Charge-Coupled Device (EBCCD) image tube, a novel instrument that combines the functions of a high-gain, gated image intensifier and a Charge-Coupled Device. Using 1-methylnaphthalene doped with 3 g/l of R45 as liquid scintillator, the attenuation lengths obtained for light propagation over distances greater than 16 cm were 1.5 m in fibres of 20 μm core and 1.0 m in fibres of 16 μm core. For particles that crossed the fibres of 20 μm core at distances of ∼1.8 cm and ∼95 cm from the fibres' readout ends, the recorded hit densities were 5.3 mm -1 and 2.5 mm -1 respectively. Using 1-methylnaphthalene doped with 3.6 g/l of R39 as liquid scintillator and fibres of 75 μm core, the hit density obtained for particles that crossed the fibres at a distance of ∼1.8 cm from their readout ends was 8.5 mm -1 . With a specially designed bundle of tapered fibres, having core diameters that smoothly increase from 16 μm to 75 μm, a spatial precision of 6 μm was measured. (orig.)

  5. Enhanced magnetodielectric and multiferroic properties of Er-doped bismuth ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, A.; Banerjee, M. [Department of Physics, National Institute of Technology, Durgapur 713209 (India); Basu, S., E-mail: soumen.basu@phy.nitdgp.ac.in [Department of Physics, National Institute of Technology, Durgapur 713209 (India); Mukadam, M.D.; Yusuf, S.M. [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Pal, M. [CSIR-Central Glass & Ceramic Research Institute, Kolkata 700032 (India)

    2015-07-15

    An enhancement in multiferroic properties has been achieved for chemically prepared BFO nanoparticles by doping with erbium (Er). XRD along with electron microscopy study reveals the phase purity and nanocrystalline nature of BFO. Enhancement of both the magnetic moment and resistivity is observed by virtue of Er doping. The observed enhanced magnetic moment is considered to be associated with smaller crystallite whereas increase of resistivity may be attributed to a decrease of oxygen vacancies. Doping also display an improvement of leakage behaviour and dielectric constant in nanocrystalline BFO, reflected in well-developed P-E loop. In addition, large enhancement in magnetodielectric coefficient is observed because of Er doping. Therefore, the results provide interesting approaches to improve the multiferroic properties of BFO, which has great implication towards its applications. - Highlights: • Synthesis of pure Er-doped BFO nanoparticles by chemical route. • Large increase in magnetic moment and resistivity due to Er doping. • Er doping produce well developed P-E loop and enhance polarization. • Drastic increase in dielectric constant as well as magnetodielectric coefficient observes because of Er doping.

  6. Real-time synchrotoron radiation X-ray diffraction and abnormal temperature dependence of photoluminescence from erbium silicates on SiO2/Si substrates

    Directory of Open Access Journals (Sweden)

    H. Omi

    2012-03-01

    Full Text Available The erbium silicate formation processes during annealing in Ar gas were monitored by synchrotron radiation grazing incidence X-ray diffraction (GIXD in real time and the optical properties of the silicates were investigated by photoluminescence measurements in spectral and time-resolved domains. The GIXD measurements show that erbium silicates and erbium oxide are formed by interface reactions between silicon oxide and erbium oxides deposited on silicon oxide by reactive sputtering in Ar gas and O2/Ar mixture gas ambiences. The erbium silicates are formed above 1060 °C in Ar gas ambience and above 1010 °C in O2/Ar gas ambience, and erbium silicides are dominantly formed above 1250 °C. The I15/2-I13/2 Er3+ photoluminescence from the erbium oxide and erbium silicate exhibits abnormal temperature dependence, which can be explained by the phonon-assisted resonant absorption of the 532-nm excitation photons into the 2H11/2 levels of Er3+ ions of the erbium compounds.

  7. New radiation-induced effects in optical fibres feasible for dosimetry

    International Nuclear Information System (INIS)

    Tomashuk, A.L.; Golant, K.M.; Dianov, E.M.; Nikolin, I.V.; Zakharkin, I.I.; Stepanov, V.A.

    1999-01-01

    Three new radiation-induced effects in silica optical fibres suitable for dosimetry are proposed: 1) in fibres with a high-OH cladding and a low-OH core, ionizing radiation disrupts the O-H bonds to let hydrogen diffuse into the core. This results in an increase in the OH-group absorption band amplitude, 2) the polymers used to coat optical fibres consist of hydrogen to the extent of about 50 %. Energetic neutrons produce recoil protons in the fibre coating, which can ''stick'' in the core, turn into hydrogen, and enter the glass network in the form of OH-group, and 3) in N-doped silica fibres irradiated with thermal neutrons, the following reaction 7 N 14 ( 0 n 1 , 1 p 1 ) 6 C 14 occurs and produces protons with energy 620 keV. With this energy, propagation length of protons in silica is 7 μm which means that the escape of protons from a 50 μm core is very weak. In fact all 3 effects lead to the irreversible increase in the OH-group absorption bands, which is proportional to the absorbed dose. With the help of these effects, temperature and dose-rate independent measurements of high doses become possible

  8. Fundamentals of fibre-reinforced soil engineering

    CERN Document Server

    Shukla, Sanjay Kumar

    2017-01-01

    This book is intended to serve as a one-stop reference on fibre-reinforced soils. Over the past 30-35 years, the engineering behaviour of randomly distributed/oriented fibre-reinforced soil, also called simply fibre-reinforced soil, has been investigated in detail by researchers and engineers worldwide. Waste fibres (plastic waste fibres, old tyre fibres, etc.) create disposal and environmental problems. Utilization of such fibres in construction can help resolve these concerns. Research studies and some field applications have shown that the fibres can be utilized in large quantities in geotechnical and civil engineering applications in a cost-effective and environmentally friendly manner. This book covers a complete description of fibres, their effects when included within a soil or other similar materials such as the fly ash, and their field applications. It gives a detailed view of fibre-reinforced soil engineering. The book will be useful to students, professional, and researchers alike, and can also ser...

  9. Laser Cooling without Repumping: A Magneto-Optical Trap for Erbium Atoms

    International Nuclear Information System (INIS)

    McClelland, J.J.; Hanssen, J.L.

    2006-01-01

    We report on a novel mechanism that allows for strong laser cooling of atoms that do not have a closed cycling transition. This mechanism is observed in a magneto-optical trap (MOT) for erbium, an atom with a very complex energy level structure with multiple pathways for optical-pumping losses. We observe surprisingly high trap populations of over 10 6 atoms and densities of over 10 11 atoms cm -3 , despite the many potential loss channels. A model based on recycling of metastable and ground state atoms held in the quadrupole magnetic field of the trap explains the high trap population, and agrees well with time-dependent measurements of MOT fluorescence. The demonstration of trapping of a rare-earth atom such as erbium opens a wide range of new possibilities for practical applications and fundamental studies with cold atoms

  10. Modelling of micromachining of human tooth enamel by erbium laser radiation

    Energy Technology Data Exchange (ETDEWEB)

    Belikov, A V; Skrypnik, A V; Shatilova, K V [St. Petersburg National Research University of Information Technologies, Mechanics and Optics, St. Petersburg (Russian Federation)

    2014-08-31

    We consider a 3D cellular model of human tooth enamel and a photomechanical cellular model of enamel ablation by erbium laser radiation, taking into account the structural peculiarities of enamel, energy distribution in the laser beam cross section and attenuation of laser energy in biological tissue. The surface area of the texture in enamel is calculated after its micromachining by erbium laser radiation. The influence of the surface area on the bond strength of enamel with dental filling materials is discussed. A good correlation between the computer simulation of the total work of adhesion and experimentally measured bond strength between the dental filling material and the tooth enamel after its micromachining by means of YAG : Er laser radiation is attained. (laser biophotonics)

  11. Modelling of micromachining of human tooth enamel by erbium laser radiation

    International Nuclear Information System (INIS)

    Belikov, A V; Skrypnik, A V; Shatilova, K V

    2014-01-01

    We consider a 3D cellular model of human tooth enamel and a photomechanical cellular model of enamel ablation by erbium laser radiation, taking into account the structural peculiarities of enamel, energy distribution in the laser beam cross section and attenuation of laser energy in biological tissue. The surface area of the texture in enamel is calculated after its micromachining by erbium laser radiation. The influence of the surface area on the bond strength of enamel with dental filling materials is discussed. A good correlation between the computer simulation of the total work of adhesion and experimentally measured bond strength between the dental filling material and the tooth enamel after its micromachining by means of YAG : Er laser radiation is attained. (laser biophotonics)

  12. Fibre optic communication key devices

    CERN Document Server

    Grote, Norbert

    2017-01-01

    The book gives an in-depth description of key devices of current and next generation fibre optic communication networks. Devices treated include semiconductor lasers, optical amplifiers, modulators, wavelength filters and other passives, detectors, all-optical switches, but relevant properties of optical fibres and network aspects are included as well. The presentations include the physical principles underlying the various devices, technologies used for their realization, typical performance characteristics and limitations, but development trends towards more advanced components are also illustrated. This new edition of a successful book was expanded and updated extensively. The new edition covers among others lasers for optical communication, optical switches, hybrid integration, monolithic integration and silicon photonics. The main focus is on Indium phosphide-based structures but silicon photonics is included as well. The book covers relevant principles, state-of-the-art implementations, status of curren...

  13. CCD technology beyond fibre optics

    International Nuclear Information System (INIS)

    Tuffen, J.

    1988-01-01

    For the past 25 years the accepted method of viewing inside industrial components, or indeed the human body, has been by the use of either flexible or rigid fibre optics. In the last five years however, many developments have enabled television cameras to reduce to a size small enough to allow internal viewing of an object, without prior dismantling. This concept was achieved five years ago, with the Welch Allyn Videoprobe 2000, a charge coupled device. (author)

  14. A discrete fibre dispersion method for excluding fibres under compression in the modelling of fibrous tissues.

    Science.gov (United States)

    Li, Kewei; Ogden, Ray W; Holzapfel, Gerhard A

    2018-01-01

    Recently, micro-sphere-based methods derived from the angular integration approach have been used for excluding fibres under compression in the modelling of soft biological tissues. However, recent studies have revealed that many of the widely used numerical integration schemes over the unit sphere are inaccurate for large deformation problems even without excluding fibres under compression. Thus, in this study, we propose a discrete fibre dispersion model based on a systematic method for discretizing a unit hemisphere into a finite number of elementary areas, such as spherical triangles. Over each elementary area, we define a representative fibre direction and a discrete fibre density. Then, the strain energy of all the fibres distributed over each elementary area is approximated based on the deformation of the representative fibre direction weighted by the corresponding discrete fibre density. A summation of fibre contributions over all elementary areas then yields the resultant fibre strain energy. This treatment allows us to exclude fibres under compression in a discrete manner by evaluating the tension-compression status of the representative fibre directions only. We have implemented this model in a finite-element programme and illustrate it with three representative examples, including simple tension and simple shear of a unit cube, and non-homogeneous uniaxial extension of a rectangular strip. The results of all three examples are consistent and accurate compared with the previously developed continuous fibre dispersion model, and that is achieved with a substantial reduction of computational cost. © 2018 The Author(s).

  15. Micro-fractional ablative skin resurfacing with two novel erbium laser systems.

    Science.gov (United States)

    Dierickx, Christine C; Khatri, Khalil A; Tannous, Zeina S; Childs, James J; Cohen, Richard H; Erofeev, Andrei; Tabatadze, David; Yaroslavsky, Ilya V; Altshuler, Gregory B

    2008-02-01

    Fractional ablation offers the potential benefits of full-surface ablative skin resurfacing while minimizing adverse effects. The purpose of this study was to evaluate the safety, damage profile, and efficacy of erbium fractional lasers. Histology from animal and human skin as well as clinical evaluations were conducted with erbium YAG (2,940 nm) and erbium YSGG (2,790 nm) fractional lasers varying pulse width, microbeam (microb) energy, number of passes, and stacking of pulses. Single-pulse treatment parameters from 1 to 12 mJ per 50-70 microm diameter microbeam and 0.25-5 milliseconds pulse widths produced microcolumns of ablation with border coagulation of up to 100 microm width and 450 microm depth. Stacking of pulses generated deeper microcolumns. Clinical observations and in vivo histology demonstrate rapid re-epithelization and limited adverse side effects. Facial treatments were performed in the periorbital and perioral areas using 1-8 passes of single and stacked pulses. Treatments were well-tolerated and subjects could resume their normal routine in 4 days. A statistically significant reduction in wrinkle scores at 3 months was observed for both periorbital and perioral wrinkles using blinded grading. For periorbital treatments of four passes or more, over 90% had > or =1 score wrinkle reduction (0-9 scale) and 42% had > or =2. For perioral wrinkles, over 50% had substantial improvements (> or =2). The clinical observations and histology findings demonstrate that micro-fractional ablative treatment with 2,790 and 2,940 nm erbium lasers resulted in safe and effective wrinkle reduction with minimal patient downtime. The depth and width of the ablated microcolumns and varying extent of surrounding coagulation can be controlled and used to design new treatment procedures targeted for specific indications and areas such as moderate to severe rhytides and photodamaged skin.

  16. Fluorescence lifetime studies of MeV erbium implanted silica glass

    International Nuclear Information System (INIS)

    Lidgard, A.; Polman, A.; Jacobsen, D.C.; Blonder, G.E.; Kistler, R.; Poate, J.M.; Becker, P.C.

    1991-01-01

    MeV erbium ion implantation into various SiO 2 glasses has been studied with the aim of incorporating the rare-earth dopant as an optically active ion in the silica network. The lifetime of the excited state ranges from 1.6 to 12.8 ms, depending on base material and implantation fluence. These results have positive implications for silica-based integrated optical technology. (Author)

  17. Fluorescence lifetime studies of MeV erbium implanted silica glass

    Energy Technology Data Exchange (ETDEWEB)

    Lidgard, A.; Polman, A.; Jacobsen, D.C.; Blonder, G.E.; Kistler, R.; Poate, J.M.; Becker, P.C. (AT and T Bell Labs., Murray Hill, NJ (USA))

    1991-05-23

    MeV erbium ion implantation into various SiO{sub 2} glasses has been studied with the aim of incorporating the rare-earth dopant as an optically active ion in the silica network. The lifetime of the excited state ranges from 1.6 to 12.8 ms, depending on base material and implantation fluence. These results have positive implications for silica-based integrated optical technology. (Author).

  18. Ion-implantation of erbium into the nanocrystalline diamond thin films

    Czech Academy of Sciences Publication Activity Database

    Nekvindová, P.; Babchenko, Oleg; Cajzl, J.; Kromka, Alexander; Macková, Anna; Malinský, Petr; Oswald, Jiří; Prajzler, Václav; Remeš, Zdeněk; Varga, Marián

    2016-01-01

    Roč. 18, 7-8 (2016), s. 679-684 ISSN 1454-4164 R&D Projects: GA ČR(CZ) GA14-05053S; GA MŠk(CZ) LM2011019 Institutional support: RVO:68378271 ; RVO:61389005 Keywords : nanocrystalline diamond * optical waveguides * erbium * luminescence * ion implantation * CVD Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.449, year: 2016

  19. Properties of epitaxial films of indium phosphides alloyed with erbium in strong electric fields

    International Nuclear Information System (INIS)

    Borisov, V.I.; Dvoryankin, V.F.; Korobkin, V.A.; Kudryashov, A.A.; Lopatin, V.V.; Lyubchenko, V.E.; Telegin, A.A.

    1986-01-01

    Temperature dependences of specific resistance and free charge-carrier mobility at low temperatures for indium phosphide films grown by liquid-phase epitaxial method with erbium additions (0.01-0.1 mass%). The main mechanisms of scattering for different temperature regions: scattering on ionized impurities in the rage from 20 to 40 K and lattice scattering at the temperature above 90 K are determined. The current density dependences on applied electric field strength are presented

  20. Erbium-ion implantation into various crystallographic cuts of Al2O3

    Czech Academy of Sciences Publication Activity Database

    Nekvindová, P.; Macková, Anna; Malinský, Petr; Cajzl, J.; Švecová, B.; Oswald, Jiří; Wilhelm, R. A.

    2015-01-01

    Roč. 365, DEC (2015), s. 89-93 ISSN 0168-583X R&D Projects: GA MŠk(CZ) LM2011019; GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:61389005 ; RVO:68378271 Keywords : Sapphire * Erbium * ion implantation * luminescence Subject RIV: CA - Inorganic Chemistry; BM - Solid Matter Physics ; Magnetism (FZU-D) Impact factor: 1.389, year: 2015

  1. Fatigue Damage Evolution in Fibre Composites for Wind Turbine Blades

    DEFF Research Database (Denmark)

    Jespersen, Kristine Munk

    on the micro-scale in the non-crimp fabric based composites used for wind turbine blades. The results show that fibre fractures in the unidirectional (UD) load carrying fibre bundles initiate from off-axis cracks in the thin supporting backing fibre bundles. With an increasing number of fatigue load cycles......, the UD fibre fractures progress gradually into the thickness direction of the UD fibre bundles, which eventually results in final fracture of the fibre composite. It is also found that the UD fibre fracture regions generally grow larger and initiate earlier at cross-over regions of the backing fibre...... bundles than at single backing fibre bundle regions. Furthermore, UD Fibre fractures are only observed to initiate at locations where the backing fibre bundles are ‘in contact’ with a UD fibre bundle. By observing the damage progression in 3D, it is also clear that the UD fibre fractures initiated...

  2. Growth and characterization of fluoride monocrystalline fibres of the type LiY1-x RExF4 (RE=rare-earths)

    International Nuclear Information System (INIS)

    Espirito Santo, Ana Maria do

    2005-01-01

    In this work we present the growth and characterization of LiF pure and rare-earth doped (Er and Nd) yttrium-lithium tetra-fluoride (LiYF 4 or YLF) by the micropulling- down technique (muPD). The use of this technique is original for the present purpose. A mu-PD prototype in the resistive mode was firstly built to understand the most important operational parameters. A commercial equipment was later installed and specifically modified to grow fluoride fibres. Regular and transparent single-crystalline fibres of LiF (diameter of 0.6 mm and length up to 150 mm) were obtained. LiF crystalline fibres as a potential laser media presented the same spectroscopic properties of bulk crystals. The influence of capillary and crucible shapes, growth atmosphere and start composition stoichiometry on the growth process of YLF fibers were also investigated. In general, the fluorides are very sensitive to moisture contamination. The growth atmosphere plays an important role on the stoichiometry deviation. Since this fluoride melts incongruently, any compositional changes influences the solidification behavior of the material. Additionally, a limited pulling rate is required to the YLF phase formation and to the compositional homogeneity along the fiber. Homogeneous and regular section YLF fibres, with diameters between 0.5 to 0.8 mm and up to 60 mm in length, were obtained in a suitable and reproducible growth process. Er-doped (with nominal concentration of 10 and 40 mol%) and Nd-doped (with nominal concentration of 1.7 mol%) fibres were also successfully grown. Er-doped fibres were crack-free and the dopant concentration was practically uniform along the YLF phase. However, Nd-doped fibres presented a short initial transient in its concentration. The Nd distribution coefficient was evaluated as 0.58 for the YLF fibre. This value is greater than those estimated for YLF bulk crystals grown by normal freezing processes. The optical properties of the YLF:Nd fibres were similar to

  3. Evaluation of safety requirements of erbium laser equipment used in dentistry

    International Nuclear Information System (INIS)

    Braga, Flavio Hamilton

    2002-01-01

    The erbium laser (Er:YAG) has been used in several therapeutic processes. Erbium lasers, however, operate with energies capable to produce lesions in biological tissues. Aiming the safe use, the commercialization of therapeutic laser equipment is controlled in Brazil, where the equipment should comply with quality and safety requirement prescribed in technical regulations. The objective of this work is to evaluate the quality and safety requirements of a commercial therapeutic erbium laser according to Brazilian regulations, and to discuss a risk control program intended to minimize the accidental exposition at dangerous laser radiation levels. It was verified that the analyzed laser can produce lesions in the skin and eyes, when exposed to laser radiation at distances smaller than 80 cm by 10 s or more. In these conditions, the use of protection glasses is recommended to the personnel that have access to the laser operation ambient. It was verified that the user's training and the presence of a target indicator are fundamental to avoid damages in the skin and buccal cavity. It was also verified that the knowledge and the correct use of the equipment safety devices, and the application of technical and administrative measures is efficient to minimize the risk of dangerous expositions to the laser radiation. (author)

  4. Factors That Improve the Impact Responses of Ukam Plant Fibre ...

    African Journals Online (AJOL)

    Natural fibres around us have mechanical properties capable of making them compete effectively with synthetic fibres in the development of fibre reinforced composites. Synthetic fibres (such as glass fibres) and resins (such as polyester resin) have long been used in the development of structural components for car bodies, ...

  5. Doping droops.

    Science.gov (United States)

    Chaturvedi, Aditi; Chaturvedi, Harish; Kalra, Juhi; Kalra, Sudhanshu

    2007-01-01

    Drug abuse is a major concern in the athletic world. The misconception among athletes and their coaches is that when an athlete breaks a record it is due to some "magic ingredient" and not because of training, hard work, mental attitude and championship performance. The personal motivation to win in competitive sports has been intensified by national, political, professional and economic incentives. Under this increased pressure athletes have turned to finding this "magic ingredient". Athlete turns to mechanical (exercise, massage), nutritional (vitamins, minerals), pharmacological (medicines) or gene therapies to have an edge over other players. The World Anti-Doping Agency (WADA) has already asked scientists to help find ways to prevent gene therapy from becoming the newest form of doping. The safety of the life of athletes is compromised with all forms of doping techniques, be it a side effect of a drug or a new technique of gene doping.

  6. Dietary fibre in foods: a review.

    Science.gov (United States)

    Dhingra, Devinder; Michael, Mona; Rajput, Hradesh; Patil, R T

    2012-06-01

    Dietary fibre is that part of plant material in the diet which is resistant to enzymatic digestion which includes cellulose, noncellulosic polysaccharides such as hemicellulose, pectic substances, gums, mucilages and a non-carbohydrate component lignin. The diets rich in fibre such as cereals, nuts, fruits and vegetables have a positive effect on health since their consumption has been related to decreased incidence of several diseases. Dietary fibre can be used in various functional foods like bakery, drinks, beverages and meat products. Influence of different processing treatments (like extrusion-cooking, canning, grinding, boiling, frying) alters the physico- chemical properties of dietary fibre and improves their functionality. Dietary fibre can be determined by different methods, mainly by: enzymic gravimetric and enzymic-chemical methods. This paper presents the recent developments in the extraction, applications and functions of dietary fibre in different food products.

  7. Frost resistance of fibre reinforced concrete structures

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan De Place

    1999-01-01

    Frost resistance of fibre reinforced concrete with 2.5-4.2% air and 6-9% air (% by volume in fresh concrete) casted in the laboratory and in-situ is compared. Steel fibres with hooked ends (ZP, length 30 mm) and polypropylene fibres (PP, CS, length 12 mm) are applied. It is shown that· addition...... of 0.4-1% by volume of fibres cannot replace air entrainment in order to secure a frost resistant concrete; the minimum amount of air needed to make the concrete frost resistant is not changed when adding fibres· the amount of air entrainment must be increased when fibres are added to establish...

  8. Theorem of comparative sensitivity of fibre sensors

    Science.gov (United States)

    Belovolov, M. I.; Paramonov, V. M.; Belovolov, M. M.

    2017-12-01

    We report an analysis of sensitivity of fibre sensors of physical quantities based on different types of interferometers. We formulate and prove the following theorem: under the time-dependent external physical perturbations at nonzero frequencies (i.e., except the static and low-frequency ones) on the sensitive arms of an interferometer in the form of multiturn elements (coils), there exist such lengths L of the measuring arms of the fibre interferometers at which the sensitivity of sensors based on the Sagnac fibre interferometers can be comparable with the sensitivity of sensors based on Michelson, Mach - Zehnder, or Fabry - Perot fibre interferometers, as well as exceed it under similar other conditions (similar-type perturbations, similar arm lengths and single-mode fibre types). The consequences that follow from the theorem, important for practical implementation of arrays of fibre sensors for measurement purposes and the devices with stable metrological properties, are discussed.

  9. Hollow Core Photonic Crystal Fibre Comprising a Fibre Grating in the Cladding and its Applications

    DEFF Research Database (Denmark)

    2010-01-01

    An optical fibre is provided having a fibre cladding around a longitudinally extending optical propagation core. The cladding has a reflection region of a varying refractive index in the longitudinal direction....

  10. [Experimental results of erbium:YAG laser vitrectomy].

    Science.gov (United States)

    Mrochen, M; Petersen, H; Wüllner, C; Seiler, T

    1998-01-01

    Vitrectomy performed by conventional guillotine devices includes the risk of mechanical damage to retina as well as other ocular structures. The present study aims to investigate the efficacy of the Er:YAG laser for vitreous liquefaction. Vitreous liquefaction by means of Er:YAG laser pulses was performed using a special handpiece. The output of an Er:YAG laser operating at 2.94 microns was coupled into a ZrF optical fibre (length 2 m) which ended inside a cavity located at the quartz tip (diameter 320 microns) of the handpiece where tissue ablation took place. The viscosity of the liquefied vitreous was determined by rotation viscosimetry and compared to liquefied vitreous obtained by mechanical vitrectomy. In addition, the aspiration flow (ml/min) was correlated to the repetition/cutting rate of the laser and the cutter. The temperature rise at the handpiece was recorded with a micro thermocouple. The cutting threshold was determined to 5 mJ +/- 3 mJ at a pulse duration of 200 microseconds. The viscosity of the vitreous liquefied with the Er:YAG laser was 31 +/- 10 mPa s which is similar to the results of mechanical vitrectomy (42 +/- 19 mPa s) but significant less than that of normal vitreous (880 +/- 280 mPa s). The aspiration of the laser handpiece in dependence to the repetition rate increases linear up to 2.6 ml/min at 30 Hz. The temperature increase at the handpiece was < 1 K under vitrectomy conditions (aspiration and irrigation) with an averaged laser power of 0.3 W (10 mJ at 30 Hz). The decreased vacuum forces used by the laser vitrectomy system may result in less mechanical stress to the retina as well as intravitreal structures which may be attached to it. An Er:YAG laser vitrectomy system may offer the potential of fewer complications during vitrectomy.

  11. Dietary fibre in foods: a review

    OpenAIRE

    Dhingra, Devinder; Michael, Mona; Rajput, Hradesh; Patil, R. T.

    2011-01-01

    Dietary fibre is that part of plant material in the diet which is resistant to enzymatic digestion which includes cellulose, noncellulosic polysaccharides such as hemicellulose, pectic substances, gums, mucilages and a non-carbohydrate component lignin. The diets rich in fibre such as cereals, nuts, fruits and vegetables have a positive effect on health since their consumption has been related to decreased incidence of several diseases. Dietary fibre can be used in various functional foods li...

  12. Influence of fibre orientation on the performance of steel fibre-reinforced concrete

    OpenAIRE

    Grünewald, Steffen; Laranjeira de Oliveira, Filipe; Walraven, Joost; Aguado de Cea, Antonio; Molins i Borrell, Climent

    2012-01-01

    The performance of fibre-reinforced materials in the hardened state depends on the material behaviour, the production method and influences related to the structure. The position and the orientation of fibres in a structure can differ from the homogenous distribution and the random orientation in a mixer. Due to the flow of the concrete, fibres are able to orient which makes the prediction of the structural behaviour of fibre-reinforced concrete more complex, but it also offers the potential ...

  13. OPTICAL FIBRES AND FIBREOPTIC SENSORS: Polarisation reflectometry of anisotropic optical fibres

    Science.gov (United States)

    Konstantinov, Yurii A.; Kryukov, Igor'I.; Pervadchuk, Vladimir P.; Toroshin, Andrei Yu

    2009-11-01

    Anisotropic, polarisation-maintaining fibres have been studied using a reflectometer and integrated optic polariser. Linearly polarised pulses were launched into the fibre under test at different angles between their plane of polarisation and the main optical axis of the fibre. A special procedure for the correlation analysis of these reflectograms is developed to enhance the reliability of the information about the longitudinal optical uniformity ofanisotropic fibres.

  14. Atomic force microscopy for the determination of refractive index profiles of optical fibres and waveguides: a quantitative study

    International Nuclear Information System (INIS)

    Huntington, S.T.; Mulvaney, P.; Roberts, K.A.

    1997-01-01

    The use of preferential etching and atomic force microscopy to measure refractive index profiles of optical fibres is investigated. Both the etch rate and the position of lateral features are shown to be independent of etch time. An elliptical core fibre has been studied and the resultant profile found to be in qualitative agreement with the preform index profile. It is shown, however, that the ellipticity of the core has changed during the drawing process. The method has been extended to fluorine and germanium doped planar waveguides and the results correlated with the fabrication process

  15. Doped Tl-1212 and Tl-1223 superconductors

    International Nuclear Information System (INIS)

    Eder, M.H.

    2001-09-01

    This work describes the preparation and characterization of thallium-lead-strontium-barium-calcium-(uranium)-copperoxide (Tl-1212, Tl-1223) high-temperature superconductors. The precursors were prepared via nitrate method. After calcination the oxidic powders were mixed with stoichiometric amounts of an Tl 2 O 3 , PbO, Er 2 O 3 and Gd 2 O 3 by milling and afterwards uniaxial compressed. Sintering was carried out in silver foils. X-ray diffractometry and high-resolution microscopy in combination with scanning electron microscopy (including EDAX) were used to study the influence of varying thallium/lead-, strontium/barium-, calcium/rare earth element ratios and the effect of uranium on the phase composition and microstructure of bulk superconductors. Furthermore the influence of the composition on the electrical and magnetical properties was studied. On phase pure Tl-1212 and Tl-1223 superconductors NMR-measurements were done. Small amounts of gadolinium and erbium instead of calcium and excess-uranium have a positive impact on the electrical and magnetical properties of the Tl-1223 superconductors. Higher amounts of these doping elements favor the Tl-1212 phase. Tl-1212 superconductors with varying thallium/lead- strontium/barium- and calcium/gadolinium ratios were prepared phasepure in wide range of doping. Transition temperatures up to 96 K were achieved. It was shown that lead has an oxidation number of +4 and thallium of +3. (author)

  16. Optical fibre radiation damage measurements

    International Nuclear Information System (INIS)

    Ediriweera, S.R.; Kvasnik, F.

    1991-01-01

    The results of studies of changes in the spectroscopic properties of commercial fibers are reported. Analysis of the attenuation spectra of various fibers have confirmed the expected different behavior of Ge-doped and pure silica fibers. However, differences in spectra of fibers made nominally from the same materials but using different processes were also observed. It is therefore concluded that the manufacturing process as well as doping determine the relative abundance of Type I and II color-center defects. The Raman spectra of the fibers were also obtained and analyzed. A strong resonant fluorescence at 650 nm, thought to be due to Type II color-centers, was observed in certain fibers. In general the changes in Raman spectra followed the theoretical expectation, however, the differences between fibers could not be entirely attributed to the doping levels. Again the manufacturing process and the subsequent treatment of fibers is thought to be partially responsible. 12 refs

  17. Fibre optic power meter calibration uncertainties

    CSIR Research Space (South Africa)

    Nel, M

    2010-06-01

    Full Text Available the patch cord, alternatively feeding into the standard or UUT is labelled ‘reference patch cord’. It is preferred to use a patch cord with a ceramic fibre tip (not metal fibre tip) to reduce reflections between the fibre tip and the detector... tightening effect To empirically quantify the effect of connector tightening, two readings are taken at each measurement, which for briefness are labelled "tight" and "un-tight". A "tight" connection is when the fibre connector is tightened...

  18. High-intensity fibre laser design for micro-machining applications

    Science.gov (United States)

    Ortiz-Neria, D. I.; Martinez-Piñón, F.; Hernandez-Escamilla, H.; Alvarez-Chavez, J. A.

    2010-11-01

    This work is focused on the design of a 250W high-intensity continuous-wave fibre optic laser with a 15μm spot size beam and a beam parameter product (BPP) of 1.8 for its use on Laser-assisted Cold Spray process (LCS) in the micro-machining areas. The metal-powder deposition process LCS, is a novel method based on Cold Spray technique (CS) assisted by laser technology. The LCS accelerates metal powders by the use of a high-pressure gas in order to achieve flash welding of particles over substrate. In LCS, the critical velocity of impact is lower with respect with CS while the powder particle is heated before the deposition by a laser beam. Furthermore, LCS does not heat the powder to achieve high temperatures as it happens in plasma processes. This property puts aside cooling problems which normally happen in sintered processes with high oxygen/nitrogen concentration levels. LCS will be used not only in deposition of thin layers. After careful design, proof of concept, experimental data, and prototype development, it should be feasible to perform micro-machining precise work with the use of the highintensity fibre laser presented in this work, and selective deposition of particles, in a similar way to the well-known Direct Metal Laser Sintering process (DMLS). The fibre laser consists on a large-mode area, Yb3+-doped, semi-diffraction limited, 25-m fibre laser cavity, operating in continuous wave regime. The fibre shows an arguably high slope-efficiency with no signs of roll-over. The measured M2 value is 1.8 and doping concentration of 15000ppm. It was made with a slight modification of the traditional MCVD technique. A full optical characterization will be presented.

  19. Abaca fibre reinforced PP composites and comparison with jute and flax fibre PP composites

    Directory of Open Access Journals (Sweden)

    2007-11-01

    Full Text Available Abaca fibre reinforced PP composites were fabricated with different fibre loadings (20, 30, 40, 50wt% and in some cases 35 and 45 wt%. Flax and jute fibre reinforced PP composites were also fabricated with 30 wt% fibre loading. The mechanical properties, odour emission and structure properties were investigated for those composites. Tensile, flexural and Charpy impact strengths were found to increase for fibre loadings up to 40 wt% and then decreased. Falling weight impact tests were also carried out and the same tendency was observed. Owing to the addition of coupling agent (maleated polypropylene -MAH-PP, the tensile, flexural and falling weight impact properties were found to increase in between 30 to 80% for different fibre loadings. When comparing jute and flax fibre composites with abaca fibre composites, jute fibre composites provided best tensile properties but abaca fibre polypropylene composites were shown to provide best notch Charpy and falling weight impact properties. Odours released by flax fibre composites were smaller than jute and abaca fibre composites.

  20. A validation of the fibre orientation and fibre length attrition prediction for long fibre-reinforced thermoplastics

    Science.gov (United States)

    Hopmann, Ch.; Weber, M.; van Haag, J.; Schöngart, M.

    2015-05-01

    To improve the mechanical performance of polymeric parts, fibre reinforcement has established in industrial applications during the last decades. Next to the widely used Short Fibre-reinforced Thermoplastics (SFT) the use of Long Fibre-reinforced Thermoplastics (LFT) is increasingly growing. Especially for non-polar polymeric matrices like polypropylene (PP), longer fibres can significantly improve the mechanical performance. As with every kind of discontinuous fibre reinforcement the fibre orientations (FO) show a high impact on the mechanical properties. On the contrary to SFT where the local fibre length distribution (FLD) can be often neglected, for LFT the FLD show a high impact on the material's properties and has to be taken into account in equal measure to the FOD. Recently numerical models are available in commercial filling simulation software and allow predicting both the local FOD and FLD in LFT parts. The aim of this paper is to compare i.) the FOD results and ii) the FLD results from available orientation- and fibre length attrition-models to those obtained from experimental data. The investigations are conducted by the use of different injection moulded specimens made from long glass fibre reinforced PP. In order to determine the FOD, selected part sections are examined by means of Computed Tomographic (CT) analyses. The fully three dimensional measurement of the FOD is then performed by digital image processing using grey scale correlation. The FLD results are also obtained by using digital image processing after a thermal pyrolytic separation of the polymeric matrix from the fibres. Further the FOD and the FLD are predicted by using a reduced strain closure (RSC) as well as an anisotropic rotary diffusion - reduced strain closure model (ARD-RSC) and Phelps-Tucker fibre length attrition model implemented in the commercial filling software Moldflow, Autodesk Inc., San Rafael, CA, USA.

  1. A validation of the fibre orientation and fibre length attrition prediction for long fibre-reinforced thermoplastics

    International Nuclear Information System (INIS)

    Hopmann, Ch.; Weber, M.; Haag, J. van; Schöngart, M.

    2015-01-01

    To improve the mechanical performance of polymeric parts, fibre reinforcement has established in industrial applications during the last decades. Next to the widely used Short Fibre-reinforced Thermoplastics (SFT) the use of Long Fibre-reinforced Thermoplastics (LFT) is increasingly growing. Especially for non-polar polymeric matrices like polypropylene (PP), longer fibres can significantly improve the mechanical performance. As with every kind of discontinuous fibre reinforcement the fibre orientations (FO) show a high impact on the mechanical properties. On the contrary to SFT where the local fibre length distribution (FLD) can be often neglected, for LFT the FLD show a high impact on the material’s properties and has to be taken into account in equal measure to the FOD. Recently numerical models are available in commercial filling simulation software and allow predicting both the local FOD and FLD in LFT parts. The aim of this paper is to compare i.) the FOD results and ii) the FLD results from available orientation- and fibre length attrition-models to those obtained from experimental data. The investigations are conducted by the use of different injection moulded specimens made from long glass fibre reinforced PP. In order to determine the FOD, selected part sections are examined by means of Computed Tomographic (CT) analyses. The fully three dimensional measurement of the FOD is then performed by digital image processing using grey scale correlation. The FLD results are also obtained by using digital image processing after a thermal pyrolytic separation of the polymeric matrix from the fibres. Further the FOD and the FLD are predicted by using a reduced strain closure (RSC) as well as an anisotropic rotary diffusion - reduced strain closure model (ARD-RSC) and Phelps-Tucker fibre length attrition model implemented in the commercial filling software Moldflow, Autodesk Inc., San Rafael, CA, USA

  2. A validation of the fibre orientation and fibre length attrition prediction for long fibre-reinforced thermoplastics

    Energy Technology Data Exchange (ETDEWEB)

    Hopmann, Ch.; Weber, M.; Haag, J. van; Schöngart, M. [Institute of Plastics Processing (IKV) at RWTH Aachen University, Pontstr. 49, 52062 Aachen (Germany)

    2015-05-22

    To improve the mechanical performance of polymeric parts, fibre reinforcement has established in industrial applications during the last decades. Next to the widely used Short Fibre-reinforced Thermoplastics (SFT) the use of Long Fibre-reinforced Thermoplastics (LFT) is increasingly growing. Especially for non-polar polymeric matrices like polypropylene (PP), longer fibres can significantly improve the mechanical performance. As with every kind of discontinuous fibre reinforcement the fibre orientations (FO) show a high impact on the mechanical properties. On the contrary to SFT where the local fibre length distribution (FLD) can be often neglected, for LFT the FLD show a high impact on the material’s properties and has to be taken into account in equal measure to the FOD. Recently numerical models are available in commercial filling simulation software and allow predicting both the local FOD and FLD in LFT parts. The aim of this paper is to compare i.) the FOD results and ii) the FLD results from available orientation- and fibre length attrition-models to those obtained from experimental data. The investigations are conducted by the use of different injection moulded specimens made from long glass fibre reinforced PP. In order to determine the FOD, selected part sections are examined by means of Computed Tomographic (CT) analyses. The fully three dimensional measurement of the FOD is then performed by digital image processing using grey scale correlation. The FLD results are also obtained by using digital image processing after a thermal pyrolytic separation of the polymeric matrix from the fibres. Further the FOD and the FLD are predicted by using a reduced strain closure (RSC) as well as an anisotropic rotary diffusion - reduced strain closure model (ARD-RSC) and Phelps-Tucker fibre length attrition model implemented in the commercial filling software Moldflow, Autodesk Inc., San Rafael, CA, USA.

  3. Non-Linear Fibres for Widely Tunable Femtosecond Fibre Lasers

    DEFF Research Database (Denmark)

    Pedersen, Martin Erland Vestergaard

    and numerically. For the intermodal four-wave mixing experiment an alternative version of the Generalised Non-Linear Schrödinger Equation is derived, which includes the correct dispersion of the transverse field. It is observed that the alternative version of the Generalised Non-Linear Schrödinger Equation......, as opposed to the commonly used version, is able to reproduce the intermodal four-wave mixing experiment. The relation between the intramodal self-phase modulation and the intramodal Raman effect is determined from experimental measurements on a number of step-index fibres. The Raman fraction is found...

  4. Influence of Impurities on the Luminescence of Er3+ Doped BaTiO3 Nanophosphors

    Directory of Open Access Journals (Sweden)

    G. D. Webler

    2014-01-01

    Full Text Available The influence of the presence of barium carbonate (BaCO3 phase on the luminescence properties of barium titanate nanocrystals (BaTiO3 powders was investigated. Structural and optical characterizations of erbium (Er3+ doped BaTiO3 synthesized by the sol-emulsion-gel were performed. Using Fourier transform infrared spectroscopy and X-ray powder diffraction, we identified the presence of impurities related to BaCO3 and quantified its fraction. It was observed that the presence of BaCO3 phase, even at low levels, depletes significantly the infrared-to-visible upconverted luminescence efficiency of the produced nanopowders.

  5. Thermoluminescence response of Ge-, Al- and Nd- doped optical fibers by 6 MeV - electron and 6 MeV - photon irradiations

    International Nuclear Information System (INIS)

    Hossain, I.; Moburak, A. A.; Saeed, M.A.; Wagiran, H.; Hida, N.; Yaakob, H.N.

    2015-01-01

    In this paper, we report the prediction of thermoluminescence responses of Neodymium-doped SiO 2 optical fibre with various dose ranges from 0.5 Gy to 4.0 Gy by 6 MeV - electron irradiations without requirement for experimental measurements. A technique has been developed to calculate prediction of 6 MeV - electron response of Neodymium-doped SiO 2 optical fibre by observing the measured TL response of 6 MV - photon and the ratio of known measured photon/electron yield ratio distribution for Ge-doped, Al-doped optical fibre and standard TLD 100 dosimeter. The samples were kept in gelatin capsule an irradiated with 6 MV - photon at the dose range from 0.5 Gy to 4.0 Gy. Siemens model Primus 3368 linear accelerator located at Hospital Sultan Ismail, Johor Bahru has been used to deliver the photon beam to the samples. We found the average response ratio of 6 MV - photon and 6 MeV - electron in Ge-doped, Al-doped optical fibre and standard TLD-100 dosimeter are 0.83(3). Observing the measured value of 6 MV - photon irradiation this average ratio is useful to find the prediction of thermoluminescence responses by 6 MeV - electron irradiation of Neodymium-doped SiO 2 optical fibre by the requirement for experimental measurements with various dose ranges from 0.5 Gy to 4.0 Gy by 6 MV - photon irradiations.

  6. Blast Resistance of Slurry Infiltrated Fibre Concrete with Waste Steel Fibres from Tires

    Directory of Open Access Journals (Sweden)

    Drdlová Martina

    2018-01-01

    Full Text Available The utilization of waste steel fibres (coming from the recycling process of the old tires in production of blast resistant cement based panels was assessed. Waste fibres were incorporated in slurry infiltrated fibre concrete (SIFCON, which is a special type of ultra-highperformance fibre reinforced concrete with high fibre content. The technological feasibility (i.e. suitability of the waste fibres for SIFCON technology was assessed using homogeneity test. Test specimens were prepared with three volume fractions (5; 7.5 and 10 % by vol. of waste unclassified fibres. SIFCON with industrial steel fibres (10% by vol. and ultra-highperformance fibre concrete with industrial fibres were also cast and tested for comparison purposes. Quasi-static mechanical properties were determined. Real blast tests were performed on the slab specimens (500x500x40 mm according to the modified methodology M-T0-VTU0 10/09. Damage of the slab, the change of the ultrasound wave velocity propagation in the slab specimen before and after the blast load in certain measurement points, the weight of fragments and their damage potential were evaluated and compared. Realized tests confirmed the possibility of using the waste fibres for SIFCON technology. The obtained results indicate, that the usage of waste fibres does not significantly reduce the values of SIFCON flexural and compressive strength at quasi-static load - the values were comparable to the specimens with industrially produced fibres. With increasing fibre content, the mechanical parameters are increasing as well. Using of the waste fibres reduces fragmentation of SIFCON at blast load due to the fibre size parameters. Using of low diameter fibres means more fibres in the matrix and thus better homogeneity of the whole composite with less unreinforced areas. Regarding the blast tests, the specimen with waste steel fibres showed the best resistance and outperformed also the specimen with commercial fibres. Using of

  7. Investigation on effect of fibre hybridization and orientation on ...

    Indian Academy of Sciences (India)

    2017-07-25

    Jul 25, 2017 ... for fibres to assess their efficiency. The first ... alternative to flax spun yarns. Bledzki et al ... Natural fibre composite are renewable, light in weight with ..... absorbs more energy due to hybridization of abaca and neem fibres.

  8. Surface treated polypropylene (PP) fibres for reinforced concrete

    Energy Technology Data Exchange (ETDEWEB)

    López-Buendía, Angel M., E-mail: buendia@uv.es [AIDICO Technological Institute of Construction, Benjamin Franklin 17, 46380 Paterna, Valencia (Spain); Romero-Sánchez, María Dolores [AIDICO Technological Institute of Construction, Marble Technical Unit, Camí de Castella 4, 03660 Novelda. Alicante (Spain); Climent, Verónica [Lafarge Cementos, Polígono Sepes, Isaac Newton s/n, 46500 Sagunto, Valencia (Spain); Guillem, Celia [AIDICO Technological Institute of Construction, Marble Technical Unit, Camí de Castella 4, 03660 Novelda. Alicante (Spain)

    2013-12-15

    Surface treatments on a polypropylene (PP) fibre have contributed to the improvement of fibre/concrete adhesion in fibre-reinforced concrete. The treatments to the PP fibre were characterized by contact angle measurements, ATR-IR and XPS to analyse chemical alterations. The surface topography and fibre/concrete interaction were analysed by several microscopic techniques, namely optical petrographic, and scanning electron microscopy. Treatment modified the surface chemistry and topography of the fibre by introducing sodium moieties and created additional fibre surface roughness. Modifications in the fibre surface led to an increase in the adhesion properties between the treated fibres and concrete and an improvement in the mechanical properties of the fibre-reinforced concrete composite as compared to the concrete containing untreated PP fibres. Compatibility with the concrete and increased roughness and mineral surface was also improved by nucleated portlandite and ettringite mineral association anchored on the alkaline PP fibre surface, which is induced during treatment.

  9. Evaluation of optical fibres as gamma radiation dosimeter

    International Nuclear Information System (INIS)

    Bohra, Dinesh; Chaudhary, H.S.; Panwar, Lalit; Vaijapurkar, S.G.; Bhatnagar, P.K.; Dasgupta, K.

    2005-01-01

    Semiconductor base gamma and neutron sensors are the fastest and popular dosimeters and are in competition with Thermoluminescence (TL) and Radio photoluminescence (RPL) dosimeters. All over the world armed forces require a dosimeter which records cumulative doses of ionizing radiations from mcGy to 10 Gy and is readable repeatedly without loss of dose information. TL dosimeters do not meet the criteria and RPL dosimeter meet the expectations and are in use by armed forces. Technologists have used laser as an excitation source to stimulate the glass and have achieved success in recording gamma doses of occupational/accidental span (mcGy to 10 Gy). However synthesizing RPL glass batches with exactly same characteristics predoses is a difficult task. Silicon base phosphorous doped step index multimode optical fibre can be made in a significant quantity and large number of dosimeters from it can be achieved with uniform predose. The radiation induced transmission loss gives a measure of gamma dose which is cumulative, readable repeatedly without loss of information. Assorted composition, core dia optical fibres have been synthesized and evaluated for dose linearity, dose rate independence, fading, length optimization. Here in is described some results of recent experiments and sensitivities achieved. (author)

  10. EXPERIMENTAL STUDY ON LIGHT TRANSMITTING CONCRETE BY USING OPTICAL FIBRE

    OpenAIRE

    S. Suganya; S. Minu Gopika

    2017-01-01

    Light transmitting concrete is one of the fibre reinforced concrete which is mainly used for aesthetic application by incorporating the optical fibres in concrete. Optical fibres help to transmit the light through the fibres and the end-light type of fibre is used to increase the aesthetic appearance of the concrete which is like a transparent concrete. Fibres are arranged in different layers, to increase the load carrying capacity and also the pattern can be created to make the concrete deco...

  11. Scintillating fibre tracking neutron detector

    International Nuclear Information System (INIS)

    Karlsson, Joakim.

    1995-04-01

    A detector for measurements of collimated fluxes of neutrons in the energy range 2-20 MeV is proposed. It utilizes (n.p) elastic scattering in scintillating optical fibres placed in successive orthogonal layers perpendicular to the neutron flux. A test module has been designed, constructed and tested with respect to separation of neutron and gamma events. The pulse height measurements show the feasibility to discriminate between neutron, gamma and background events. Application to measurements of fusion neutrons is considered. 18 refs, 22 figs, 4 tabs

  12. France's State of the Art Distributed Optical Fibre Sensors Qualified for the Monitoring of the French Underground Repository for High Level and Intermediate Level Long Lived Radioactive Wastes.

    Science.gov (United States)

    Delepine-Lesoille, Sylvie; Girard, Sylvain; Landolt, Marcel; Bertrand, Johan; Planes, Isabelle; Boukenter, Aziz; Marin, Emmanuel; Humbert, Georges; Leparmentier, Stéphanie; Auguste, Jean-Louis; Ouerdane, Youcef

    2017-06-13

    This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo's severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA) responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution.

  13. Winding of fibre composites; Vikling af fiberkompositter

    Energy Technology Data Exchange (ETDEWEB)

    Lystrup, Aage

    2006-01-01

    Within the project 'Storage of hydrogen in advanced high pressure vessels' under the PSO-R AND D 2005 program one of the tasks is to describe the technology, which is used for manufacturing of fibre reinforced pressure vessels. Fibre reinforced pressure vessels for high pressures are manufactured by winding structural load bearing fibres around a mandrel or an internal liner. There are two different types of cylindrical pressure vessels: 1) Cylinders with thick metal liner, where only the cylindrical part is over wrapped with hoop windings, and 2) cylinders with a thin metal or polymer liner, where both the cylindrical part and the end domes are over wrapped with more layers with different fibre orientations (helical and hoop windings). This report describes the fundamental principles for filament winding of fibre reinforced polymer composites. After a short introduction to the advanced fibre composites, their properties and semi-raw materials used for fibre composites, the focus is on the process parameters, which have influence on the material quality of filament wound components. The report is both covering winding of fibre reinforced thermo-setting polymers as well as thermoplastic polymers, and there are references to vendors of filament winding machines, accessory equipment and computer software for design and manufacturing of filament wound components. (au)

  14. Step index fibre using laser interferometer

    Indian Academy of Sciences (India)

    2014-03-04

    Mar 4, 2014 ... We propose the following model to describe the cladded fibre placed inside a liquid wedge interferometer. For simplicity, we assume square interferometer plates of dimensions 2a,. 2b and refractive index μL. The fibre radius is rf and the core radius is rc with skin and core indices μs, μc respectively. Hence ...

  15. Fibre digestion in the hyra;r

    African Journals Online (AJOL)

    dried samples by calorimeter combustion. The fibre con- tent was determined by the method of Van Soest (1964) us- ing a Fibretec 1020 hot extraction apparatus. Two-way analysis of variance was used to test for differences between the two most important fibre digesting gut regions, the sac- culation and caeca. Results.

  16. Mohair, cashmere and other animal hair fibres

    CSIR Research Space (South Africa)

    Hunter, L

    2012-11-01

    Full Text Available Although luxury animal fibres, excluding silk, represent far less than 0.1% of global fibre production, they play a very significant role in the luxury, high value-added end of the market, notably the apparel market, being renowned for their special...

  17. Mohair, cashmere and other animal hair fibres

    CSIR Research Space (South Africa)

    Hunter, L

    2012-11-01

    Full Text Available and mostly unique features, such as comfort and softness. This chapter covers the production, properties, processing and end-uses of the various luxury animal fibres, with the exclusion of silk, with the main focus on the down (undercoat) fibres of those...

  18. Insertion of optic fibre for CMS

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    The MicroJET system uses high pressure to carefully put the optical fibres into their protective tubes. These fibres are vital for rapid data transfer, but are also very delicate and, if damanged, may not work at the required efficiency. Similiar methods are used to install cables for the telecommunications industry.

  19. Deformation quantization of principal fibre bundles

    International Nuclear Information System (INIS)

    Weiss, S.

    2007-01-01

    Deformation quantization is an algebraic but still geometrical way to define noncommutative spacetimes. In order to investigate corresponding gauge theories on such spaces, the geometrical formulation in terms of principal fibre bundles yields the appropriate framework. In this talk I will explain what should be understood by a deformation quantization of principal fibre bundles and how associated vector bundles arise in this context. (author)

  20. Microstructural characterization of stone wool fibre network

    DEFF Research Database (Denmark)

    Chapelle, Lucie; Brøndsted, Povl; Kusano, Yukihiro

    2014-01-01

    Understanding the mechanical properties of fibrous network as complex as stone wool materials requires a relevant description of their microstructure and architecture. In this study, different methods have been proposed to characterize the fibre orientation, diameter and length of fibres as well...