﻿ 激光拉丝形状对太赫兹能量空间分布影响的研究
 光学仪器  2020, Vol. 42 Issue (6): 54-58 PDF

Research on the influence of the shape of the laser plasma on terahertz energy spatial distribution
XU Bowei
School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
Abstract: In order to understand and explain the influence factors of terahertz energy spatial distribution from the physical mechanism, the influence of the shape of the laser plasma on terahertz energy spatial distribution was studied. By using a cylindrical lens instead of a spherical lens to focus laser, a plasma sheet is produced, and the terahertz energy spatial distribution generated by the plasma sheet is collected. The results show that the shape of the plasma itself not only directly affects the spatial distribution of terahertz energy, but also affects the influence of pump laser’s polarization changing to the spatial distribution of terahertz energy.
Key words: terahertz    spatial energy distribution    cylindrical lens    plasma sheet

You等[17]在研究中发现，在双色场拉丝条件下，远场太赫兹能量在空间整体基本呈对称的圆环状分布。虽然不同频率分量的太赫兹在同一探测平面上能量空间分布的圆环大小不同（高频太赫兹波能量分布圆环直径小，低频太赫兹波能量分布圆环直径大），但是整体始终呈现为对称的圆环状分布。而如果在此条件下改变泵浦光的偏振，太赫兹能量的空间分布基本不产生变化。

1 实验原理

 图 1 实验装置 Figure 1 Experiment setup

 图 2 四分之三象限太赫兹波挡板示意图 Figure 2 Three-quarter quadrant THz wave baffle.
2 实验结果及分析

 图 3 用球面透镜拉丝时太赫兹能量的空间分布 Figure 3 The spatial distribution of terahertz energy when using a spherical lens to generate terahertz

 图 4 片状拉丝为水平方向时太赫兹能量的空间分布 Figure 4 The spatial distribution of terahertz energy with horizontal plasma sheet

3 结　论

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