超快激光成丝产生太赫兹波的研究

研究了超快激光脉冲成丝辐射太赫兹(Terahertz, THz)波.考虑到THz 波在安全检查和国防建设等方面具有十分重要的意义, 文中总结了超快激光成丝产生太赫兹波的物理机制和控制技术, 并对各种相关理论和技术进行了分析.文章从理论模型、偏振特性和远场角分布情况等方面来介绍物理机制, 并探讨为满足应用需求的控制技术, 主要包括强度、偏振和波形控制.研究表明, 超快激光成丝辐射太赫兹波的产生方式、理论模型和控制形式均有多种, 其中理论模型主要包括四波混频模型和光电流模型, 强度控制技术主要包括双色场泵浦和在光丝通道两侧施加偏压.

Study of terahertz radiation from filamentation induced by ultrafast laser pulses

Terahertz (THz) radiation from femtosecond photo-induced gas plasmas was explored. Given that THz wave is of great importance in safety inspection and national defense, it was summarized and analyzed that physical mechanism, which covers theory model, polarization characteristic and angle distribution of far field, and control technologies consisting of control of THz intensity, polarization and waveform to meet application requirements was discussed. It shows that there are many ways to generate, explain and control THz radiation from laser-induced plasmas. Among them theory models mainly include four wave mixing model and photocurrent model, and high energy of THz emission could be radiated from two-color femtosecond laser-induced filament in air or generated in laser-induced air plasma on the external electric field.