多色飞秒激光场产生高能量超宽带太赫兹辐射的研究进展  

Research Progress on Intense and Broadband Terahertz Radiation Generation with Multi⁃Color Laser Field

作　　者：卢晨晖 庄龙振 张志文 刘则甫 刘一 Lu Chenhui;Zhuang Longzhen;Zhang Zhiwen;Liu Zefu;Liu Yi(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海工程技术大学机械与汽车工程学院,上海201620 [2]上海理工大学光电信息与计算机工程学院,上海200093

出　　处：《中国激光》2023年第17期81-95,共15页Chinese Journal of Lasers

基　　金：国家自然科学基金(12034013)。

摘　　要：飞秒激光聚焦在空气中能够产生高能量超宽带的太赫兹辐射,这种强场太赫兹辐射在物态操控、太赫兹通信、生物医学成像等领域具有重要的应用价值。采用双色乃至多色激光场是提高气体等离子体中太赫兹辐射强度的关键路径之一。本文回顾了多色场驱动空气等离子体太赫兹辐射源的发展历程,按照单色场、双色场到三色场的发展脉络,从实验方案、理论原理、优化探索三方面综述了国内外多色飞秒光场驱动气体等离子体太赫兹辐射的研究现状和最新成果,并对该方向的未来发展进行了展望。Significance The terahertz(THz)radiation spectrum,lying between the infrared and microwave regimes,encompasses a wide range of energy levels of lattice vibrations and molecular rotations in matter.Hence,THz radiation has potential applications in fields including matter manipulation,nondestructive testing,and biomedical imaging.However,a key challenge hindering the application of THz radiation is the need to further improve its energy and intensity.Therefore,exploring techniques for producing high-energy THz radiation remains a major focus and hot topic.One method for generating intense THz radiation involves the nonlinear interaction between high-energy,ultrafast laser pulses and gases,resulting in a remarkably wide bandwidth of approximately 200 THz.This exceeds other commonly used THz radiation sources,such as optical-conductive antennas or optical rectification crystals,which are usually limited to a bandwidth below 5 THz.Furthermore,air-based THz sources offer advantages over solid-state sources,including immunity to laser damage and renewable properties,making them a pivotal for generating powerful and wide-ranging THz radiation.An early study involving air plasma-based THz sources employed a one-color femtosecond laser pulse(usually with a wavelength near 800 nm from a Ti∶Sapphire laser)for THz generation.A two-color scheme,combining the fundamental laser field and its second harmonic,has also been intensively studied over the past 20 years.For the two-color scheme,it was revealed that the asymmetry of the two-color optical field plays a crucial role in generating high-intensity THz radiation.Nevertheless,the asymmetry of the optical field provided by the two-color field remains limited.Hence,there is a strong incentive to utilize multi-color laser fields to optimize the conversion efficiency of THz radiation,while also enabling manipulation of its properties.Progress This paper provides a comprehensive review of THz generation techniques based on air plasma,with an emphasis on the evolution from one-col

关 键 词：非线性光学 太赫兹技术 强场太赫兹辐射源 多色飞秒激光场 激光与等离子体相互作用 

分 类 号：O437[机械工程—光学工程]