The Experts below are selected from a list of 33033 Experts worldwide ranked by ideXlab platform
Changxi Yang - One of the best experts on this subject based on the ideXlab platform.
-
Tailoring birefringence and polarization coupling in Photonic Crystal Fibers
Photorefractive Fiber and Crystal Devices: Materials Optical Properties and Applications X, 2004Co-Authors: Changxi Yang, Lin ZhangAbstract:We report on the birefringence of Photonic Crystal Fibers as functions of fiber structure parameters and incident wavelength. It is found that the sign of the fiber birefringence can be changed by controlling the incident wavelength. The guided-mode coupling properties of the dual-core Photonic Crystal Fibers are highly engineerable by tailoring the birefringence. New types of polarization splitters based on the Photonic Crystal Fibers are presented.
-
Photonic Crystal Fibers with squeezed hexagonal lattice.
Optics express, 2004Co-Authors: Lin Zhang, Changxi YangAbstract:We study the birefringence and polarization coupling in the index-guiding Photonic Crystal Fibers (PCFs) with squeezed hexagonal Crystal lattice. The sign of form birefringence in such Photonic Crystal Fibers can be changed as the wavelength changes, which is reported for the first time to our knowledge. A PCF-based polarization splitter with squeezed hexagonal lattice is proposed to achieve excellent extinction ratio and a simpler structure than those reported previously.
-
Polarization splitter based on Photonic Crystal Fibers
Optics express, 2003Co-Authors: Lin Zhang, Changxi YangAbstract:We report a new kind of polarization splitter based on dual-core Photonic Crystal Fibers. The polarization splitter has a symmetric directional coupler configuration. Each core exhibits high birefringence, which gives rise to an adequate difference in the coupling lengths for the two orthogonal polarizations. A 1.7-mm-long splitter is obtained with the splitting ratio better than -11 dB and a bandwidth of 40 nm. The relationship between the length of the polarization splitter and the diameter of the air hole in the middle of the two cores is discussed.
Masanori Koshiba - One of the best experts on this subject based on the ideXlab platform.
-
chromatic dispersion profile optimization of dual concentric core Photonic Crystal Fibers for broadband dispersion compensation
Optics Express, 2006Co-Authors: Takeshi Fujisawa, Kunimasa Saitoh, Keisuke Wada, Masanori KoshibaAbstract:Chromatic dispersion profile of dual-concentric-core Photonic Crystal Fibers is optimized for broadband dispersion compensation of single mode Fibers (SMFs) by using genetic algorithm incorporated with full-vector finite-element method. From the numerical results presented here, it is found that by increasing the distance between central core and outer ring core, larger negative dispersion coefficient and better dispersion slope compensation are possible. There is a tradeoff between the magnitude of negative dispersion coefficient and dispersion slope compensation due to the concave dispersion profile of dual-concentric-core Photonic Crystal Fibers. In spite of the tradeoff, dual-concentric-core Photonic Crystal Fibers having larger negative dispersion coefficient as well as compensating for dispersion slope of SMFs in the entire C band with large effective area can be designed.
-
numerical modeling of Photonic Crystal Fibers
Journal of Lightwave Technology, 2005Co-Authors: Kunimasa Saitoh, Masanori KoshibaAbstract:Recent progress on numerical modeling methods for Photonic Crystal Fibers (PCFs) such as the effective index approach, basis-function expansion approach, and numerical approach is described. An index-guiding PCF with an array of air holes surrounding the silica core region has special characteristics compared with conventional single-mode Fibers (SMFs). Using a full modal vector model, the fundamental characteristics of PCFs such as cutoff wavelength, confinement loss, modal birefringence, and chromatic dispersion are numerically investigated.
-
Numerical Investigation of Raman Amplification Properties in Photonic Crystal Fibers
Optical Amplifiers and Their Applications, 2005Co-Authors: Shailendra K. Varshney, Kunimasa Saitoh, Masanori KoshibaAbstract:A full-vectorial finite-element method is used to investigate Raman amplification properties of Photonic Crystal Fibers. Raman gain of 9 dB is obtained in 4-km length of PCF with a high optical signal-to-noise ratio.
-
Polarization splitter in three-core Photonic Crystal Fibers.
Optics express, 2004Co-Authors: Kunimasa Saitoh, Yuichiro Sato, Masanori KoshibaAbstract:A novel design of polarization splitter in three-core Photonic Crystal Fibers (PCFs) has been proposed. The three-core PCF consists of two given identical cores with two-fold symmetry separated by a core with high birefringence. The polarization splitter is based on the phenomenon of resonant tunneling. Numerical simulations with a full vectorial beam propagation method demonstrate that it is possible to obtain a 1.9-mm-long splitter with the extinction ratio better than -20 dB and a bandwidth of 37 nm.
Alexandre Kudlinski - One of the best experts on this subject based on the ideXlab platform.
-
Control of surface Brillouin scattering in Photonic Crystal Fibers
2016Co-Authors: Joel Cabrel Nougnihi, Jeancharles Beugnot, Thibaut Sylvestre, Vincent Laude, Kien Huy, Alexandre KudlinskiAbstract:We report the firstexperimentalobservationof surface Brillouin scattering in Photonic Crystal Fibers(PCFs)arisingfrom interaction between light and surface acoustic waves (SAWs).Wealsoshow thatthis new type of lightscatteringis highly sensitive to the PCFair-hole microstructure, thus providing a passiveand efficient way to controlit.Our observations areconfirmed throughnumerical simulations ofthe elastodynamics equation
-
Enhanced soliton self-frequency shift and CW supercontinuum generation in GeO2 -doped core Photonic Crystal Fibers
Journal of the Optical Society of America B, 2011Co-Authors: Benoît Barviau, Gilles Melin, Olivier Vanvincq, Arnaud Mussot, Yves Quiquempois, Alexandre KudlinskiAbstract:We investigate the impact of germanium oxide ( GeO2 ) doping on the linear and nonlinear properties of Photonic Crystal Fibers. We propose some design rules allowing a strong enhancement of the Raman and Kerr nonlinearities with little impact on the fiber dispersive properties. It is experimentally and numerically demonstrated that using GeO2 -doped core Photonic Crystal Fibers allows a significant enhancement of the soliton self-frequency shift as compared to pure silica Photonic Crystal Fibers with comparable dispersion. We found that the high nonlinear coefficient (due to a good mode confinement) obtained in the GeO2 -doped core fiber plays a more important role on the soliton self-frequency shift enhancement than the intrinsic Raman gain.
-
dispersion engineered Photonic Crystal Fibers for cw pumped supercontinuum sources
Journal of Lightwave Technology, 2009Co-Authors: Alexandre Kudlinski, Geraud Bouwmans, M Douay, Majid Taki, Arnaud MussotAbstract:We report recent advances on the spectral control of continuous-wave-pumped supercontinuum sources. We show that the generated infrared SC spectrum can be tailored by using Photonic Crystal Fibers with two zero-dispersion wavelengths. The dynamics of the spectral broadening is studied, and we show that slightly different nonlinear mechanisms occur as the zero-dispersion wavelengths are brought closer to each other. We also report the generation of a visible continuous-wave-pumped supercontinuum by using dispersion engineered Photonic Crystal Fibers in which the zero-dispersion wavelength slightly decreases as a function of length over 200 m. The resulting supercontinuum source spans from 650 nm to 1380 nm with an average output power of 19.5 W. The nonlinear mechanisms producing this spectacular effect are carefully investigated with support of numerical simulations. We show that the generation of visible wavelengths is due to the trapping of dispersive waves by powerful red-shifting solitons.
Thibaut Sylvestre - One of the best experts on this subject based on the ideXlab platform.
-
Control of surface Brillouin scattering in Photonic Crystal Fibers
2016Co-Authors: Joel Cabrel Nougnihi, Jeancharles Beugnot, Thibaut Sylvestre, Vincent Laude, Kien Huy, Alexandre KudlinskiAbstract:We report the firstexperimentalobservationof surface Brillouin scattering in Photonic Crystal Fibers(PCFs)arisingfrom interaction between light and surface acoustic waves (SAWs).Wealsoshow thatthis new type of lightscatteringis highly sensitive to the PCFair-hole microstructure, thus providing a passiveand efficient way to controlit.Our observations areconfirmed throughnumerical simulations ofthe elastodynamics equation
-
Surface Brillouin scattering in Photonic Crystal Fibers
Optics Letters, 2016Co-Authors: Joel Cabrel Tchahame Nougnihi, Jeancharles Beugnot, Vincent Laude, Kien Phan Huy, A Kudlinski, Thibaut SylvestreAbstract:We report, to the best of our knowledge, the first experimental observation of surface Brillouin scattering in silica-based Photonic Crystal Fibers, arising from the interaction between guided light and surface acoustic waves. This was achieved using small-core and high air-filling fraction microstructured Fibers that enable a strong opto-acoustic coupling near the air holes while mitigating the acoustic leakages in the microstructured cladding. It is further shown that this new type of light scattering is highly sensitive to the fiber air-hole microstructure, thus providing a passive and efficient way to control it. Our observations are confirmed through numerical simulations of the elastodynamics equation.
-
guided acoustic wave brillouin scattering in Photonic Crystal Fibers
Optics Letters, 2007Co-Authors: Jeancharles Beugnot, Thibaut Sylvestre, Herve Maillotte, Gilles Melin, Vincent LaudeAbstract:We experimentally investigate guided acoustic wave Brillouin scattering in several Photonic Crystal Fibers by use of the so-called fiber loop mirror technique and show a completely different dynamics with respect to standard all-silica Fibers. In addition to the suppression of most acoustic phonons, we show that forward Brillouin scattering in Photonic Crystal Fibers is substantially enhanced only for the fundamental acoustic phonon because of efficient transverse acousto-optic field overlap. The results of our numerical simulations reveal that this high-frequency phonon is indeed trapped within the fiber core by the air-hole microstructure, in good agreement with experimental measurements.
Lin Zhang - One of the best experts on this subject based on the ideXlab platform.
-
Tailoring birefringence and polarization coupling in Photonic Crystal Fibers
Photorefractive Fiber and Crystal Devices: Materials Optical Properties and Applications X, 2004Co-Authors: Changxi Yang, Lin ZhangAbstract:We report on the birefringence of Photonic Crystal Fibers as functions of fiber structure parameters and incident wavelength. It is found that the sign of the fiber birefringence can be changed by controlling the incident wavelength. The guided-mode coupling properties of the dual-core Photonic Crystal Fibers are highly engineerable by tailoring the birefringence. New types of polarization splitters based on the Photonic Crystal Fibers are presented.
-
Photonic Crystal Fibers with squeezed hexagonal lattice.
Optics express, 2004Co-Authors: Lin Zhang, Changxi YangAbstract:We study the birefringence and polarization coupling in the index-guiding Photonic Crystal Fibers (PCFs) with squeezed hexagonal Crystal lattice. The sign of form birefringence in such Photonic Crystal Fibers can be changed as the wavelength changes, which is reported for the first time to our knowledge. A PCF-based polarization splitter with squeezed hexagonal lattice is proposed to achieve excellent extinction ratio and a simpler structure than those reported previously.
-
Polarization splitter based on Photonic Crystal Fibers
Optics express, 2003Co-Authors: Lin Zhang, Changxi YangAbstract:We report a new kind of polarization splitter based on dual-core Photonic Crystal Fibers. The polarization splitter has a symmetric directional coupler configuration. Each core exhibits high birefringence, which gives rise to an adequate difference in the coupling lengths for the two orthogonal polarizations. A 1.7-mm-long splitter is obtained with the splitting ratio better than -11 dB and a bandwidth of 40 nm. The relationship between the length of the polarization splitter and the diameter of the air hole in the middle of the two cores is discussed.