太赫兹波辐射源的研究进展

Research Progress of Terahertz Wave Radiation Source

电磁波谱中的太赫兹波段拥有许多比传统光源更独特的性质,在生物、材料、安检和通信等领域有着非常重要的研究价值,而高功率和高效率的太赫兹辐射源则是太赫兹技术转化为实际生产力的一个重要因素和前提条件。文章分别从以气体、固体和液体作为激发介质的角度,总结了激光与不同激发介质相互作用产生太赫兹波的研究进展。对气体介质中常用的四波混频、有质动力、切伦科夫和光电流模型的物理机制以及固体介质中的光电导和光整流模型的物理机制进行了详细撰述,并对影响这几种激发介质产生出太赫兹波的因素进行了分析与总结。最后,对液体激发介质产生出太赫兹辐射源的方法进行了展望。

Terahertz band in electromagnetic spectrum has many properties than traditional light source,which has very important research value in biology,material,security,communication and other fields.The high power and high efficiency terahertz radiation source is an important factor and prerequisite for the transformation of terahertz technology into actual productivity.In this paper,the research progress of terahertz wave generated by laser interacting with different excitation media is summarized from the perspective of gas,solid and liquid as excitation media.The physical mechanism of four-wave mixing,mass-dynamic,cherenkov and photocurrent models commonly used in gas media,as well as the physical mechanism of photoconductance and photorectification models in solid media are described in detail,and the factors affecting the generation of terahertz waves by these excitation media are analyzed and summarized.Finally,the methods of producing terahertz radiation source by liquid excited medium are prospected.