等离子体随机分布对THz波传输特性的影响  

Effect of random distribution of plasma on transmission characteristics of THz waves

作　　者：张洁[1] 杨光华 ZHANG Jie;YANG Guang-hua(College of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070,Gansu,China)

机构地区：[1]西北师范大学物理与电子工程学院,甘肃兰州730070

出　　处：《西北师范大学学报（自然科学版）》2022年第4期58-65,共8页Journal of Northwest Normal University(Natural Science)

基　　金：甘肃省科技计划资助项目(20JR10RA080)。

摘　　要：高超声速飞行器再入过程中在其周围会产生非均匀的等离子体鞘套流场,同时在飞行器飞行姿态调整,流场分界层湍流、层流相互转换以及再入过程中由于强烈摩擦产生的高温等因素的影响下,使得产生的鞘套具备了一定的随机特性.文中通过改变磁化角度和外加磁场强度、等离子体电子密度、电子密度相对变化幅度以及碰撞频率等参数,提出了基于等离子体随机分布的散射矩阵法来研究THz波传播的相关特性的方法.结果表明,THz波的极化方向不同,其透射率的变化趋势也不同;左极化波在随机分布等离子体中的透射率要优于右极化波;通过调控合适的物理量,可改变THz波在具有随机特性等离子体中的透射特性.该研究结果对于缓解高超声速飞行器与地面之间的通信“黑障”问题具有一定的参考价值.During the reentry process of the hypersonic vehicle,a non-uniform plasma sheath flow field will be generated around it.At the same time,during the flight attitude adjustment of the aircraft,the turbulent flow in the boundary layer of the flow field,the laminar flow mutual conversion and the high temperature due to strong friction during the reentry process.Under the influence of other factors,the resulting sheath has certain random characteristics.In this paper,a scattering matrix method based on the random distribution of plasma is proposed to study the relevant characteristics of THz wave propagation by changing the magnetization angle and the strength of the external magnetic field,the plasma electron density,the relative change strength of the electron density and the collision frequency.The final results show that the polarization direction of THz wave is different,and the change trend of its transmittance is also different.The transmittance of left-polarized wave in randomly distributed plasma is better than that of right-polarized wave.By manipulating appropriate physical quantities,the transmission characteristics of THz waves in plasmas with random properties can be changed.The research results have certain reference value for alleviating the“black barrier”problem of communication between hypersonic aircraft and the ground.

关 键 词：非均匀磁化等离子体 随机特性 磁化角度 散射矩阵法 

分 类 号：O53[理学—等离子体物理]