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Chinese Physics B 2011年第5期20卷 294-299页

作者：苑金辉桑新柱余重秀忻向军申向伟张锦龙周桂耀李曙光侯蓝田 Key Laboratory of Information Photonics and Optical Communications(BUPT) of Ministry of Education Institute of Optical Communication and OptoelectronicsBeijing University of Posts and Telecommunications Institute of Infrared Optical Fibers and Sensors College of Information Science and EngineeringYanshan University

By coupling a train of femtosecond pulses with 100 fs pulse width at a repetition rate of 76 MHz generated by a mode-locked Ti： sapphire laser into the fundamental mode of photonic crystal fibre （PCF） with central holes fabricated through extracting air from the central hole, the broad and ultra-flattened supercontinuum （SC） in the visible wavelengths is generated. When the fundamental mode experiences an anomalous dispersion regime, three phases in the SC generation process are primarily presented. The SC generation （SCG） in the wavelength range from 470 nm to 805 nm does not emerge significant ripples due to a higher pump peak power and the corresponding mode fields at different wavelengths are observed using Bragg gratings. The relative intensity fluctuations of output spectrum in the wavelength ranges of 530 nm to 640 nm and 543 nm to 590 nm are only 0.028 and 0.0071, respectively.

关键词： photonic crystal fibre (PCF) fundamental mode broad and ultra-flattened supercontinuum visible wavelengths

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Cavity fundamental mode and beam interaction in CEPC main ring

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Radiation Detection Technology and Methods 2018年第1期2卷 113-121页

作者： Dianjun Gong Jie Gao Jiyuan Zhai Dou Wang Institute of High Energy Physics BeijingChina University of Chinese Academy of Sciences 100049 BeijingChina

Background CEPC is a 100-kilometer-long electron-position collider,aiming to produce Higgs,W and *** ring(DR)is the baseline design of its main ring,and advanced partial double ring(APDR)is the alternative *** The purpose of this paper is to study the beam loading effects and the corresponding longitudinal beam dynamics of CEPC DR and *** The phase shift of the bunches modulated by the bunch gap is calculated with the approximation formulas and simulated with the *** these methods are compared,and the application conditions of them are also *** addition,the longitudinal coupled-bunch instability in CEPC main ring is calculated by analytical *** In CEPC DR high-lumi Z,the phase shift can be reduced to 0.51 deg(°).Besides,the total number of unstable longitudinal modes is 15 in CEPC DR high-lumi Z when no feedback system is *** The phase shift of the bunches in CEPC can be reduced to an acceptable value if the optimal filling pattern is *** CEPC APDR,the RF parameters are calculated and the beam loading effects are tolerable.

关键词： CEPC Main ring fundamental mode Beam loading Phase shift CBI

Numerical Solution of The fundamental mode of Photonic Crystal Fibers

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Numerical Solution of The Fundamental Mode of Photonic Cryst...

A dark hollow beam from a selectively liquid-filled photonic crystal fibre

2012管理创新、智能科技与经济发展研讨会

作者： Peiying CHEN 1,Lanzhu AN 2,Suqin FENG 3,Haixu SONG 4 123 Physics Department,Xingtai University,Xingtai City,Hebei,PR China 054001 4 Xingtai Contemporary Vocational School,Xingtai City,PR China,054001

The modes for optical fibers and photonic crystal fibers are analyzed by employing the Finite Difference method,which is used to solve the eigenvalue *** the critical V parameter the relative core size of the core for single mode is *** varying the pitch,rectangular air hole width and applying a scale version wave equation with propagation rate equations solvers,the field distribution of the fundamental mode of photonic crystal fibers have been simulated.

关键词： Photonic Crystal Fibers(Pcfs) fundamental mode Wavelength Wave Equations.

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Chinese Physics B 2010年第4期19卷 339-344页

作者：张美艳李曙光姚艳艳付博张磊 Key Laboratory of Metastable Materials Science and Technology College of ScienceYanshan University

This paper reports that, based on the electromagnetic scattering theory of the multipole method, a high-quality hollow beam is produced through a selectively liquid-filled photonic crystal fibre. Instead of a doughnut shape, a typical hollow beam is produced by other methods; the mode-field images of the hollow-beam photonic crystal fibre satisfy sixth-order rotation symmetry, according to the symmetry of the photonic crystal fibre （PCF） structure. A dark spot size of the liquid-filled photonic crystal fibre-generated hollow beam can be tuned by inserting liquid into the cladding region and varying the photonic crystal fibre structure parameters. The liquid-filled PCF makes a convenient and flexible tool for the guiding and trapping of atoms and the creation of all-fibre optical tweezers.

关键词： liquid-filled photonic crystal fibre fundamental mode dark hollow beam

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Effect of Plasma Density on Proton Acceleration in a Rectangular Waveguide

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Plasma Science and Technology 2004年第5期6卷 2456-2458页

作者： Hitendra K.Malik Department of Physics Indian Institute of Technology DelhiNew Delhi-110016Indianalytical studies are made for the proton acceleration during its motion in thefields of the fundamental mode excited by a high-intensity microwave in a rectangular waveguidewhen the proton is injected along the propagating direction of the mode. The trajectory of theproton is calculated and the expressions are obtained for the energy gain and acceleration gradienttogether with the effects of plasma density microwave frequency and waveguide width. Energygain of 181 keV is attained by a 50 keV proton in a 0.015m×0.020 m evacuated waveguide when0.5×10~(10)W/m~2 microwave intensity is used. However this gain increases to 1387 keV whenthe waveguide is filled with a plasma having a density of 1.0×10~(19) m~(-3). Higher accelerationgradients are achieved when the proton is injected with a higher initial energy and also when themicrowave intensity increases. The effects of the microwave frequency and width of the waveguideare found to decrease the acceleration gradient.

Analytical studies are made for the proton acceleration during its motion inthe fields of the fundamental mode excited by a high-intensity microwave in a rectangular waveguide,when the proton is injected along the propagating direction of the mode. The trajectory of theproton is calculated and the expressions are obtained for the energy gain and acceleration gradienttogether with the effects of plasma density, microwave frequency and waveguide width. Energy gain of181 keV is attained by a 50 keV proton in a 0.015m x 0.020 m evacuated waveguide when 0.5 x 10^(10)W/m^2 microwave intensity is used. However, this gain increases to 1387 keV when the waveguide isfilled with a plasma having a density of 1.0 x 10^(19) m^(-3). Higher acceleration gradients areachieved when the proton is injected with a higher initial energy and also when the microwaveintensity increases. The effects of the microwave frequency and width of the waveguide are found todecrease the acceleration gradient.

关键词： proton acceleration microwave fundamental mode

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波导CO2激光器的非匹配光腔

厦门大学学报(自然科学版) 1987年第4期 425-429页

作者：周世昌厦门大学物理学系

本文报道了波导CO2激光器的一种选择横模的方法,该器件采用了大孔径波导和近场非匹配凹面镜,可得较高输出功率的基模激光.

关键词： Waveguide Laser Non-matching resonator fundamental mode