太赫兹时域光谱(THz-TDS)技术是一种使用相干探测的频谱分析手段。THz-TDS系统集太赫兹波发射器与探测器于一体,通过相干探测,可以同时获取太赫兹脉冲的电场强度和相位信息,广泛用于生物、材料、安检等领域。超快激光成丝产生太赫兹波是当前产生宽频谱、高强度太赫兹辐射的一个重要途径。文章详细介绍了超快激光成丝辐射太赫兹波的主流物理机制以及增强、调控太赫兹波的主要方法,阐述了基于激光成丝的THz-TDS系统的探测原理和探测手段。

Terahertz time-domain spectroscopy (THz-TDS) uses coherent detection method for spectrum analysis. The THz-TDS system integrates terahertz emitter and detector, which can simultaneously acquire the field intensity and phase information of terahertz pulses and be widely used in biology, materials, security, and other fields. The THz pulse induced by the ultrafast laser filament is an important way to generate wide-spectrum and high-intensity THz radiation. In this paper, the physical mechanisms of ultrafast laser filament radiated THz waves and the methods of enhancing and regulating THz waves are introduced in detail. The detection principle and methods of the THz-TDS system based on laser filamentation are described.