偏振方向对THz电光探测影响的理论研究

Effect of polarization of THz pulse and probe pulse on THz electro-optic detection

采用线性电光效应耦合波理论,系统地研究了用无中心反演对称性的立方晶系晶体作为探测晶体时,terahertz(THz)辐射信号和探测光的偏振方向对电光探测的影响.研究结果发现,THz辐射和探测光的偏振方向都对电光探测影响很大,沿(110)方向传播时可以获得最大的探测灵敏度,最适合THz的横场探测.计算研究的部分结果与已有的实验结果相一致,可为电光探测器的设计提供有用的指导.

We studied the effect of polarization of terahertz pulse and probe beam on terahertz detection in optically isotropic detection crystals using wave coupling theory of linear electro-optic effect. The study results show that the effect is remarkable, and the detection can get its largest sensitivity when the probe beam propagates along （110） direction which is most suitable for terahertz detection. Some of the study results are in good agreement with the previously published experimental results. So our study is helpful for the design of electro-optic detectors.