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Photonic Sensors 2018年第2期8卷 188-192页

作者： Xiaofei JIA College of Electronic and Information Engineering Ankang University Ankang 725000 China

Starting from the basic equations describing the evolution of the carriers and photons inside a semiconductor optical amplifier （SOA）, the equation governing pulse propagation in the SOA is derived. By employing homotopy analysis method （HAM）, a series solution for the output pulse by the SOA is obtained, which can effectively characterize the temporal features of the nonlinear process during the pulse propagation inside the SOA. Moreover, the analytical solution is compared with numerical simulations with a good agreement. The theoretical results will benefit the future analysis of other problems related to the pulse propagation in the SOA.

关键词： Semiconductor optical amplifier pulse propagation homotopy analysis method series solution

Simulation of Chirped pulse propagation in Silicon Nanowires: Shape and Spectrum Analysis

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Optics and Photonics Journal 2016年第8期6卷 53-61页

作者： Hassan Pakarzadeh Zeinab Delirian Mostafa Taghizadeh Department of Physics Shiraz University of Technology Shiraz Iran Atomic and Molecular Group Faculty of Physics Yazd University Yazd Iran

In this paper, we simulate the propagation of chirped pulses in silicon nanowires by solving the nonlinear Schrodinger equation (NLSE) using the split-step Fourier (SSF) method. The simulations are performed both for the pulse shape (time domain) and for the pulse spectrum (frequency domain), and various linear and nonlinear effects changing the shape and the spectrum of the pulse are analyzed. Owing to the high nonlinear coefficient and a very small effective-mode area, the required length for observing nonlinear effects in nanowires is much shorter than that of conventional optical fibers. The impacts of loss, nonlinear effects, second- and third-order dispersion coefficients and the chirp parameter on pulse propagation along the nanowire are investigated. The results show that the sign and the value of the chirp parameter have important role in pulse propagation so that in the anomalous dispersion regime, the compression occurs for the up- chirped pulses, whereas the broadening takes place for the down-chirped pulses. The opposite situation happens for up- and down-chirped pulses propagating in the normal dispersion regime.

关键词： Silicon Nanowire Nonlinear Schrödinger Equation Chirp pulse propagation

A Study on pulse propagation on Double Side PCB

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A Study on Pulse Propagation on Double Side PCB

The Effect of the Width of the Incident pulse to the Dielectric Transition Layer in the Scattering of an Electromagnetic pulse–a Qubit Lattice Algorithm Simulation

The Fourth Asia-Pacific Conference on Environmental Electromagnetics

作者： Atsuo Mutoh Shuichi Nitta Kouta Hasegawa Tsuneo Tsukagoshi Tokyo Fuji University 3-8-1 Takadano-baba Shinjuku Tokyo 169-0075Japan Salesian Polytechnic 4-6-8 Oyamagaoka Machida Tokyo 194-0215Japan Salesian Polytechnic 4-6-8 Oyamagaoka Machida Tokyo 194-0215Japan NEC Co. Ltd. 1120 Shimokusawa SagamiharaKanagawa 229-1198Japan

＜正＞This paper clarifies the differential mode pulse propagation characteristics on the parallel plates consisting of DC power supply plane and its return plane, from the viewpoint of series resonance of parallel plates, experimentally and by PSPICE simulation. It is concluded that the practical pulse propagation characteristics are dominated by the characteristics of not only the parallel plates but also the wirings connected to the parallel plates.

关键词： pulse propagation parallel plates resonance ESD PSPICE simulation

来源： cnki会议评论

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Communications in Computational Physics 2023年第1期33卷 22-38页

作者： George Vahala Linda Vahala Abhay K.Ram Min Soe Department of Physics William&MaryWilliamsburgVA23185USA Department of Electrical&Computer Engineering Old Dominion UniversityNorfolkVA 12319USA Plasma Science and Fusion Center MITCambridgeMA 02139USA Department of Mathematics and Physical Sciences Rogers State UniversityClaremoreOK 74017USA

The effect of the thickness of the dielectric boundary layer that connects amaterial of refractive index n1 to another of index n2 is considered for the propagation of an electromagnetic pulse.A qubit lattice algorithm(QLA),which consists of a specially chosen non-commuting sequence of collision and streaming operators acting on a basis set of qubits,is theoretically determined that recovers theMaxwell equations to second-order in a small parameterǫ.For very thin but continuous boundary layer the scattering properties of the pulse mimics that found from the Fresnel discontinuous jump conditions for a plane wave-except that the transmission to incident amplitudes are augmented by a factor of√n2/*** the boundary layer becomes thicker one finds deviations away from the discontinuous Fresnel conditions and eventually one approaches the expectedWKB *** there is found a small but unusual dip in part of the transmitted pulse that persists in ***,the QLA simulations still recover the solutions to Maxwell equations even when this parameterǫ→*** examining the pulse propagation in medium n1,ǫcorresponds to the dimensionless speed of the pulse(in lattice units).

关键词： Unitary algorithms qubits Maxwell equations pulse propagation

propagation of Solitary pulses in Optical Fibers with Both Self-Steepening and Quintic Nonlinear Effects

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Communications in Theoretical Physics 2014年第6期61卷 735-741页

作者：李金花 C.Rogers K.W.Chow K.S.Chiang School of Physics and Optoelectronic Engineering Nanjing University of Information Science and Technology Australian Research Council Centre of Excellence for Mathematics & Statistics of Complex Systems School of Mathematics The University of New South Wales Department of Mechanical Engineering University of Hong Kong Department of Electronic Engineering City University of Hong Kong

pulse dynamics and stability in optical fibers in the presence of both self-steepening and quintic nonlinear effects are analyzed. Propagating profiles of the quintic derivative nonlinear Schr¨odinger model are isolated via two invariants of motion. The resulting canonical equation admits exact periodic propagating patterns in terms of the Jacobi elliptic functions, and solitary pulses are recovered in the long wave limit, i.e. degenerate cases of periodic profiles where each pulse is widely separated from the adjacent ones. Two families of such exact wave profiles are identified. The first one has a precise constraint concerning the magnitude of self-steepening and quintic nonlinear effects, while the second one permits more freedom. The reduction to the well established temporal soliton in an optical fiber waveguide in the absence of self-steepening and quintic nonlinearity is demonstrated explicitly. Numerical simulations are performed to identify regimes of parameter values where robust propagation patterns exist.

关键词： cubic-quintie nonlinear Schrodinger equation self-steepening pulse propagation

Spatiotemporal evolution of continuous-wave field and dark soliton formation in a microcavity with normal dispersion

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Chinese Physics B 2017年第7期26卷 167-172页

作者：胡晓鸿张伟刘元山冯野张文富王擂然王屹山赵卫 State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center of Extreme Optics Shanxi University

Stable dark soliton and dark pulse formation in normally dispersive and red-detuned microcavities are investigated by numerically solving the normalized Lugiato-Lefever equation. The soliton essence is proved by fitting the calculated field intensity profile with the analytical formula of a dark soliton. Meanwhile, we find that a dark soliton can be generated either from the nonlinear evolution of an optical shock wave or narrowing of a locally broad dark pulse with smoother fronts. Explicit analytical expression is obtained to describe the oscillatory fronts of the optical shock wave. Furthermore,from the calculation results, we show that for smaller frequency detunings, e.g., α 3, in addition to the dark soliton formation, a single dark pulse with an oscillatory dip can also arise and propagate stably in the microcavity under proper pump detuning and pump strength combination. The existence region together with various field intensity profiles and the corresponding spectra of single dark pulse are demonstrated.

关键词： pulse propagation temporal solitons microcavities nonlinear optics

Precise control of micro-rod resonator free spectral range via iterative laser annealing

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Chinese Optics Letters 2021年第7期19卷 77-81页

作者： Qin Wen Wenwen Cui Yong Geng Heng Zhou Kun Qiu Key Laboratory of Optical Fiber Sensing and Communication Networks School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731China

We demonstrate a novel method to control the free spectral range(FSR) of silica micro-rod resonators *** method is accomplished by iteratively applying laser annealing on the already-fabricated micro-rod *** and repeatable increasing of resonator FSR is demonstrated, and the best resolution is smaller than 5 MHz, while the resonator quality-factor is only slightly affected by the iterative annealing *** the fabricated micro-rod resonators, single dissipative Kerr soliton microcombs are generated, and soliton repetition frequencies are tuned precisely by the iterative annealing *** demonstrated method can be used for dual-comb spectroscopy and coherent optical communications.

关键词： microcavities nonlinear optics pulse propagation temporal solitons

Stability and a fast calculation method of travel speed of pulse peak in convergence zone

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1274-1282页

作者： REN Yun ZHANG RenHe WANG Jun GUO YongGang Luo WenYu State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

A long-range sound propagation experiment was conducted in the West Pacific Ocean in summer *** signals received by a towed array indicate that the travel speed of pulse peak(TSPP)in the convergence zones is ***,an equivalent sound speed can be used at all ranges in the convergence zones.A fast calculation method based on the beam-displace-ment ray-mode(BDRM)theory and convergence zone theory is proposed to calculate this equivalent sound *** computation speed of this proposed method is over 1000 times faster than that of the conventional calculation method based on the normal mode theory,with the computation error less than 0.4%compared with the experimental ***,the effect of frequency and sound speed profile on the TSPP is studied with the conventional and fast calculation methods,showing that the TSPP is almost independent of the frequency and sound speed profile in the ocean surface layer.

关键词： travel speed pulse peak pulse propagation BDRM theory turning point convergence zone

Heat Transport of Non-Local Effect with Modulated SMBI on HL-2A

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Chinese Physics Letters 2009年第3期26卷 163-165页

作者：孙红娟丁玄同姚良骅冯北滨刘泽田商亚东李伟李雪泓段旭如杨青巍 Southwestern Institute of Physics PO Box 432 Chengdu 610041

Modulated supersonic molecular beam （SMB） injection is introduced to study transport features of non-local transport phenomenon on HL-2A. Repetitive non-local effect induced by modulated SMBI allows Fourier trans-formation of the temperature perturbation, yielding detailed investigation of the pulse propagation. Fourier analysis provides evidence for existence of internal transport barriers. Meanwhile, experimental progress of nonlocal effect was made in the HL-2A Tokamak in 200Z The core electron temperature Te rise increases from 18% to more than 40% and the duration of the Te rise could be prolonged by changing the conditions of SMB injection.

关键词： TOKAMAK PLASMAS Plasmas Heat transport pulse propagation transport Server Message Block Fourier Transform Tokamak devices

Theoretical analysis on waveform structures of pulse propagating in shallow water with an ideal thermocline

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Chinese Journal of Acoustics 1995年第2期14卷 133-143页

作者： ZHU Ye ZHANG Renhe and JIN Guoliang(State Key Loboratory of Acoustics. Institute of Acoustics. Academia Sinica. Beijing 100080)

In this paper, waveforms of band-limited signals are calculated under the assumptionof ideal thermocline by using the ray-mode theory with beam displacement (RMB). Comparison between the RMB approach and MOATL codes shows that the RMB approach is a fast and accurate one and the run time by the RMB approach is reduced by at least two orders of magnitude. Results reveal that the beam displacement plays a key role in waveform calculation under the condition of thermocline, and the validity on the formula of mode attenuation coefficient with beam displacement is further proved. The -dependencies of waveforms of pulse signals on source-receiver depths, transmission range, signal frequency, and bottom parameters are discussed.

关键词： pulse propagation Multipath structures Beam displacement