可产生任意偏振方向太赫兹波的光电导太赫兹辐射源

A Photoconductive Terahertz Radiation Source Generating Terahertz Waves with Arbitrary Polarization Direction

基于太赫兹时域光谱(THz-TDS)系统,使用两个相互垂直的光电导天线构建了1×2 GaAs光电导太赫兹源阵列.通过调控各个阵元的偏置电压,对其辐射太赫兹波的偏振方向进行研究.结果表明:在已实现光电导发射天线阵列的高效合成以及可同时检测脉冲太赫兹波的振幅、相位及偏振态的探测天线的基础上,通过调控各个阵元的偏置电压分别改变了平行和垂直两个阵元辐射太赫兹波的强度;经过1×2 GaAs光电导太赫兹源阵列在远场的同步合成,可产生不同偏振方向的脉冲太赫兹波,实现了以全电控的方式产生任意偏振方向太赫兹波的光电导太赫兹辐射源.

Based on terahertz time domain spectral(THz-TDS)system,we use two mutually perpendicular photoconductive antennas construct a 1×2 GaAs photoconductive terahertz source array.Its radiation terahertz wave polarization direction is studied by adjusting the bias voltage of each array element.The results indicate that,on the basis of the efficient synthesis of photoconductive emission antenna arrays and the detection antenna that can simultaneously detect the amplitude,phase and polarization state of pulsed terahertz waves,the intensity of terahertz waves radiated by two parallel and vertical elements are changed by adjusting the bias voltage of each array element.After 1×2 GaAs photoconductive terahertz source array synchronously synthesized in the far field,pulse terahertz waves with different polarization directions are generated,realizing a photoconductive terahertz radiation source that can generate terahertz waves with arbitrary polarization direction in a fully electrically controlled manner.