椭圆偏振太赫兹辐射偏振态的单发测量

Single-Shot Detection of Polarization State for Elliptically Polarized Terahertz Radiation

利用超强超短激光光源中激光-等离子体的相互作用,能够产生毫焦耳量级高能量的太赫兹辐射,而这种条件下产生的太赫兹辐射通常是单发的。针对该类型太赫兹辐射提出一种单发测量方案:将太赫兹波分束,用两套独立校准的啁啾脉冲光谱编码探测装置,分别同时测量太赫兹电场在水平和竖直方向上的分量,最终得到太赫兹电场的偏振态。基于所提方案进行了实验验证,用单发测量原理得到了太赫兹辐射的偏振态。实验测得的椭偏度与模型分析吻合,验证了所提单发测量方案的可行性,为单发椭偏太赫兹辐射偏振态的测量研究提供了新思路。

Powerful terahertz(THz) radiation is generated by the interaction between laser and plasma of a super short laser source;such THz radiation is usually single-shot. Herein, we propose a single-shot measurement strategy that involves splitting the THz beam, measuring the THz radiation in the horizontal and vertical directions using two independent spectral detection systems with chirped pulses, and finally obtaining the polarization state. We perform a proof experiment based on this strategy and measure an elliptically polarized THz waveform via the single-shot method. Experimental results agree well with the model analysis, verifying the feasibility of our strategy in addition to providing a new plan for single-shot detection of the polarization state of elliptically polarized THz radiation.