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Influence of Waveguide Properties on Wave Prototypes Likely to Accompany the Dynamics of Four-Wave Mixing in Optical Fibers

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Journal of Applied Mathematics and Physics 2024年第7期12卷 2601-2633页

作者： Jean Roger Bogning Marcelle Nina Zambo Abou’ou Christian Regis Ngouo Tchinda Mathurin Fomekong Oriel Loh Ndichia Stallone Mezezem Songna François Béceau Pelap Department of Physics Higher Teacher Training College University of Bamenda Bamenda Cameroon African Optical Fiber Family Bafoussam Cameroon Department of Physics Faculty of Science University of Bamenda Bamenda Cameroon Department of Physics Faculty of Science University of Yaound I Yaound Cameroon Africain en Technologie de lInformation et de la Tlcommunication The University of Yaound I Yaound Cameroon Unit de Recherche de Mcanique et de Modlisation des Systmes Physiques (UR-2MSP) Facult des Sciences Universit de Dschang Dschang Cameroun

In this article, we study the impacts of nonlinearity and dispersion on signals likely to propagate in the context of the dynamics of four-wave mixing. Thus, we use an indirect resolution technique based on the use of the iB-function to first decouple the nonlinear partial differential equations that govern the propagation dynamics in this case, and subsequently solve them to propose some prototype solutions. These analytical solutions have been obtained;we check the impact of nonlinearity and dispersion. The interest of this work lies not only in the resolution of the partial differential equations that govern the dynamics of wave propagation in this case since these equations not at all easy to integrate analytically and their analytical solutions are very rare, in other words, we propose analytically the solutions of the nonlinear coupled partial differential equations which govern the dynamics of four-wave mixing in optical fibers. Beyond the physical interest of this work, there is also an appreciable mathematical interest.

关键词： Optical Fiber Four Waves Mixing Implicit Bogning Function Coupled nonlinear Partial Differential Equations nonlinear coefficient Dispersive coefficient Waveguide Properties

ESTIMATE ACCURACY OF nonlinear coefficientS OF SQUEEZEFILM DAMPER USING STATE VARIABLE FILTER METHOD

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Chinese Journal of Mechanical Engineering 1998年第3期11卷 13-19页

作者： Zhang, Youyun Roberts, J.B. Xian Jiaotong Univ Xian China

The estimate model for a nonlinear system of squeeze film damper (SFD) is *** method of state variable filter (SVF) is used to estimate the coefficients of *** factors which are critical to the estimate accuracy are ... 详细信息

关键词： nonlinear coefficient Squeeze film State variable filter Parameter estimate

Design on a highly birefringent and nonlinear photonic crystal fiber in the C waveband

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Chinese Physics B 2014年第4期23卷 310-313页

作者：李端明周桂耀夏长明王超苑金辉 Laboratory of Nanophotonic Functional Materials and Devices South China Normal University State Key Laboratory of Metastable Materials Science and Technology Yanshan University

In this paper, a novel photonic crystal fiber （PCF） with high birefringence and nonlinearity is designed. The charac- teristics of birefringence, dispersion and nonlinearity are studied by using the full-vector finite element method （FVFEM）. The numerical results show that the phase birefringence and nonlinear coefficient of PCF can be up to 4.51× 10-3 and 32.8972 ***-1 at 1.55 μm, respectively. The proposed PCF could be found to have important applications in the polarization-dependent nonlinear optics such as the pulse compress and reshaping in the C waveband.

关键词： high birefringence nonlinear coefficient zero dispersion wavelength full-vector finite elementmethod

Effect of Ge–GeO_2 co-doping on non-ohmic behaviour of TiO_2–V_2O_5–Y_2O_3 varistor ceramics

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Journal of Semiconductors 2015年第7期36卷 39-44页

作者：康昆勇甘国友严继康易建宏张家敏杜景红赵文超荣雪全 Faculty of Materials Science and Engineering Kunming University of Science and Technology Key Laboratory of Advance Materials of Yunnan Province Key Laboratory of Advance Materials of Precious-Nonferrous Metals Ministry of Education

An investigation was made into the effect of doping with the elemental crystal Ge or/and GeO2 on the TiO2-V2O5-Y2O3 varistor ceramics. The result shows that as the doping contents of V2O5 and Y2O3 are 0.5 tool%, respectively, co-doping with 0.3 mol% Ge and 0.9 mol% GeO2 makes the highest α value （α = 12.8）, the lowest breakdown voltage Vlmg （VlmA = 15.8 V/ram） and the highest grain boundary barrier ФB （ФB = 1.48 eV）, which is remarkably superior to the TiO2-V2Os-Y203 varistor ceramics undoped with Ge and GeO2 and mono-doped with Ge or GeO2. The TiO2-V2Os-YEO3-Ge-GeO2 ceramic has the prospect of becoming a novel varistor ceramic with excellent electrical properties.

关键词： TiO2 varistor co-doping nonlinear coefficient breakdown voltage Ge and GeO2

Influence of soaking time on nonlinear electrical behavior and dielectric properties of TiO_2-based varistor ceramics

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Journal of Central South University 2009年第6期16卷 897-901页

作者：孟凡明鲁飞肖磊孙兆奇 School of Physics and Materials Science Anhui University State Key Laboratory of Materials Modification by Laser Ion and Electron BeamsDalian University of Technology Anhui Key Laboratory of Information Materials and Devices Anhui University

The influence of soaking time on the nonlinear electrical behavior and dielectric properties of TiO2-based varistor ceramics was investigated. Based on single sintering process, six disk samples of （Sr, Bi, Si, Ta）-doped TiO2-based varistor ceramics were fabricated by sintering at 1 250 ℃ for 0.5-5.0 h. The samples were characterized by X-ray diffraction, voltage-current characteristics, energy spectra, metallographs, breakdown voltages, and apparent dielectric constant. It is found that the breakdown electrical field intensity at a current density of 10 mA/cma decreases from 5.5 to 4.1 V/mm first and then increases to 7.0 V/mm, the nonlinear coefficient increases from 2.39 to 2.62 first and then decreases to 2.42, and the apparent dielectric constant increases from 98 200 to 1l5 049 first and then decreases to 73 865 with the soaking time increasing from 0.5 to 5.0 h. These indicate that the optimal soaking time is 2.0-3.0 h considering both nonlinear electrical behavior and dielectric properties.

关键词： TiO2 varistor ceramics breakdown voltage nonlinear coefficient dielectric constant soaking time

Effect of sintering temperature on microstructure and nonlinear electrical characteristics of ZnO varistor

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Journal of Advanced Dielectrics 2018年第2期8卷 67-71页

作者： Ahmed Bouchekhlal Farida Hobar Microsystems and Instrumentation Laboratory University of Constantine 25017 Algeria

The nonlinear properties of ZBMCCS-based varistors,which are composed of ZnO-Bi_(2)O_(3)-MnO_(2)-Cr_(2)O_(3)-Sb_(2)O_(3)-Co_(3)O_(4) and SiO_(2) are studied inrelation to sintering temperature,in the range of 1280–1350℃.The samples are investigated for grain morphology by using scanning electron microscope(SEM).These samples were examined by using X-ray diffraction patterns(XRD)and DC electrical measurements.X-ray diffraction analysis of the samples show the presence of ZnO,Zn_(2)SiO_(4) willemite phase and Co_(2.33)Sb_(0.67)O_(4) spinel *** average grain size of ZnO increased as the sintering temperature increased from 2.57 to 6.84*** the examined temperature range,the breakdown field decreased from 2992 to 127 V/cm with the increase of sintering *** system gives a relatively high nonlinearity coefficientα=33.61(at a sintering temperature of 1280℃)with a low leakage current of 0.21 mA/cm^(2).

关键词： ZnO varistor ceramics microstructure nonlinear coefficient sintering temperature

Influence of Annealing Atmosphere on Varistor Property of TiO2-Nb2O5-SrCO3Ceramics

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Materials Sciences and Applications 2021年第11期12卷 461-474页

作者： Kunyong Kang Haodong Zhu Gang Zhu Shuduan Deng Functional and Wood-Based Ceramics Laboratory Southwest Forestry University Kunming China School of Materials Science and Engineering Southwest Forestry University Kunming China

Varistor ceramics are typical electronic ceramics, which are widely used in circuits of overvoltage protection, high voltage stabilization and high energy surge absorption. TiO2 varistor ceramics has the advantages of low varistor voltage and good dielectric properties, but their low nonlinearity limited the application. The influence of annealing on the varistor properties of TiO2-Nb2O5-SrCO3 ceramics was investigated in this paper. TiO2-Nb2O5-SrCO3 varistor ceramics were prepared by the traditional method of ball grinding-forming-sintering and they were annealed in oxygen and nitrogen, respectively. The nonlinear coefficient α and the breakdown voltage EB of the samples were tested using the varistor dc parameter meter. The microstructure of samples was analyzed by XRD, SEM, STEM-EDAX and SAEDP. The results show that during annealing, Sr2+ ions with a larger radius obtain the kinetic energy and are segregated to grain boundaries, which increases the acceptor density of the grain boundaries and improves α. Annealing in an oxygen atmosphere, the enrichment of oxygen at grain boundaries is also helpful to increase the density of acceptor states and the height of the potential barrier, so as to further increase α. Meanwhile, annealing makes crystalline grains grow properly, which results in even grain size, reduces the porosity and increases the density of grains. So EB tends to reduce. As the doping concentration of Nb2O5 and SrCO3 is 0.15 mol%, respectively, and sintering temperature is 1300°C, TiO2-Nb2O5-SrCO3 varistor ceramics annealed in oxygen for 3 h at 750°C achieved the highest nonlinear coefficient α = 8.9 and t

关键词： TiO2 nonlinear coefficient Breakdown Voltage Annealing Atmosphere

Dielectric and varistor properties of rare-earth-doped ZnO and CaCu_(3)Ti_(4)O_(12) composite ceramics

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Journal of Advanced Dielectrics 2013年第1期3卷 19-22页

作者： Huafei Lu Yuanhua Lin Jiancong Yuan Cewen Nan Kexin Chen State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084P.R.China

To investigate the multi-functional ceramics with both high permitivity and large nonlinear cofficient,we have prepared rare-earth Tb-and-Co doped ZnO and TO_(2)rich CaCu_(3)Ti_(4)O_(12)(TCCTO)powders by chemical co-precipitation and sol-gel methods re-spectively,and then obtained the TCCTO/ZnO composite ceramics,sintered at 1100℃for 3h in *** the composite ceramics of the microstructure and phase composition indicated that the composite ceramics were composed of the main phases of ZnO and CaCu_(3)Ti_(4)O_(12)(CCTO).Our results revealed that the TCCTO/ZnO composite ceramics showed both high dielectric and good nonlinear electrical *** composite ceramic of TCCTO:ZnO=0.3 exhibited a high dielectric constant of~210(1 kHz)with a nonlinear cofficient of~*** dielectric behavior of TCCTO/ZnO composite could be explained by the mixture *** the high dielectric permittivity and tunable varistor behaviors,the composite ceramics has a potential application for the higher voltage transportation devices.

关键词： Varistors CCTO nonlinear coefficient dielectrics