基于气体特征吸收谱线的太赫兹时域光谱仪频率校准

摘要

提出一种基于气体特征吸收谱线的太赫兹时域光谱仪(THz-TDS)的频率校准方法.通过将THz-TDS测量结果与CO在THz波段的特征吸收谱线标准数据进行比较,对THz-TDS光学延时线运动速度控制不精确造成的光谱测量线性误差进行了修正,从而实现了THz-TDS的频率校准,修正后的THz-TDS频率测量平均误差为3.1 GHz.%We presented a technique for frequency calibration of terahertz time-domain spectrometers (THz-TDS) using absorption lines of carbon monoxide (CO). By comparing the peak positions of absorption lines between measured results and standard data, the linearity error caused by the optical delay line was modified so as to achieve the frequency calibration. After modifying, the mean error of the peak positions measured by our THz-TDS was 3. 1 GHz. The results show that CO is suitable for frequency calibration of THz-TDS.