为了探究甲醇气体在太赫兹波段的共振特性,利用太赫兹时域光谱对甲醇气体进行了测量,得到了其时域波形,观测到了自由感应衰变这一现象。根据朗博比尔定律对气体吸收谱的计算得到转动谱线间隔,并对自由感应衰变这一现象进行了深入的解释,这些结果对于太赫兹波段的气体检测、分析和识别具有参考价值。

In order to investigate the resonance characteristics of gaseous methanol in the terahertz region,gaseous methanol was measured by using the terahertz time-domain spectroscopy.The time-domain waveform and the free induction decay phenomenon were observed.By calculating the gas absorption spectra with Beer-Lambert law,we obtained the interval of rotational lines of methanol.The phenomenon of the free induction decay was explained in depth from these results.The results have reference value for the detection,analysis and identification of gas in the terahertz region.