Propagation dynamics of relativistic electromagnetic solitary wave as well as modulational instability in plasmas

作     者：Rong-An Tang Tiao-Fang Liu Xue-Ren Hong Ji-Ming Gao Rui-Jin Cheng You-Lian Zheng Ju-Kui Xue 唐荣安;刘调芳;洪学仁;高吉明;程瑞锦;郑有莲;薛具奎

作者机构：Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu ProvinceCollege of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2021年第30卷第1期

页      面：332-344页

核心收录：

学科分类：07[理学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 070204[理学-等离子体物理] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11765017,11865014,11847304,and 11764039) the Scientific Research Project of Gansu Higher Education,China(Grant No.2019B-034) the Science and Technology Project of Guizhou Province,China(Grant No.QiankeheLH-20177008) 

主　　题：electromagnetic solitary wave particle-in-cell(PIC)simulation modulational instability Langmuir oscillation 

摘      要：By one-dimensional particle-in-cell(PIC) simulations, the propagation and stability of relativistic electromagnetic(EM) solitary waves as well as modulational instability of plane EM waves are studied in uniform cold electron-ion *** investigation not only confirms the solitary wave motion characteristics and modulational instability theory, but more importantly, gives the following findings. For a simulation with the plasma density 10^(23) m^(-3) and the dimensionless vector potential amplitude 0.18, it is found that the EM solitary wave can stably propagate when the carrier wave frequency is smaller than 3.83 times of the plasma frequency. While for the carrier wave frequency larger than that, it can excite a very weak Langmuir oscillation, which is an order of magnitude smaller than the transverse electron momentum and may in turn modulate the EM solitary wave and cause the modulational instability, so that the solitary wave begins to deform after a long enough distance propagation. The stable propagation distance before an obvious observation of instability increases(decreases) with the increase of the carrier wave frequency(vector potential amplitude). The study on the plane EM wave shows that a modulational instability may occur and its wavenumber is approximately equal to the modulational wavenumber by Langmuir oscillation and is independent of the carrier wave frequency and the vector potential *** reveals the role of the Langmuir oscillation excitation in the inducement of modulational instability and also proves the modulational instability of EM solitary wave.