周期量级圆偏振激光脉冲在空气中成丝产生太赫兹辐射的研究

项目名称： 周期量级圆偏振激光脉冲在空气中成丝产生太赫兹辐射的研究

项目编号： No.61308022

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 宋立伟

作者单位： 中国科学院上海光学精密机械研究所

项目金额： 24万元

中文摘要： 本项目旨在研究周期量级圆偏振激光脉冲在空气中成丝所辐射出太赫兹波的波形、振幅、偏振状态等性质及其与驱动激光载波-包络相位的关系。首先，在理论上，根据光电流模型和传播方程，在给定的激光条件下,分析成丝过程中太赫兹辐射的强度和偏振状态并得出各参数与激光载波-包络相位的关系。然后，重点进行实验方面的工作：1、对周期量级圆偏振激光脉冲在空气中成丝辐射的太赫兹波进行参数测量，包括能量、波形、偏振状态等，并对比长脉冲和线偏振激光驱动的情形；2、改变激光的载波-包络相位，测量太赫兹波的偏振方向、波形、振幅的变化，与理论分析相互印证。本项目的意义在于：一方面，通过驱动激光参数的改变，实现对成丝辐射的太赫兹波的波形和偏振方向的控制，丰富了对激光成丝过程的认识，并有很大的应用价值；另一方面，通过太赫兹波偏振方向的测量推算出驱动激光的载波-包络相位，这对阿秒科学研究具有重要意义。

中文关键词： 太赫兹波；少周期激光；偏振；载波-包络相位；

英文摘要： The purpose of this project is to study the characters of terahertz emission from air plasma produced by few-cycle circularly polarized laser pulses, such as waveform, amplitude and polarization. And relationship between the characters and the carrier-envelope phase of driving laser will be also dicussed.Firstly, according to the photocurrent model and the propagation equation,the amplitude and polarization of terahertz emission from the filament will be caculated under given laser status, and their dependance on carrier-envelope will be obtained.Then, we'll lay the amphasis on experimental research: 1) Parameter measurement of tearhertz emission from air plasma produced by few-cycle circularly polarized laser pulses, including intensity, waveform, and polarization. And comparison to the condition of driving by multi-cycle and linearly polarization pulses. 2) Measurement of the terahertz parameters under various carrier-envelope phases, and comparing with theoretical analysis.The significance of the project is obviously. On one side, the waveform and polarization of terahertz generated from air plasma will be controllable by adjusting the parameters of driving laser. This will enrich our knowledge about laser driving plasma and will have a great application value.On the other side, the carrier-envelpe phase of d

英文关键词： terahertz pulses；few-cycle laser；polarization；carrier-envelope phase；