Millimeter Wave Spectroscopy by Snchrotron Radiation

在分子科学研究所(冈崎)的电子储存环设施UVSOR上使用电子加速器(SR)作为非常明亮的光源进行了毫米波光谱研究。首先，对专门用于远红外光谱的光学系统进行了改进，使其可以用于毫米波光谱。利用改进后的光学系统与随机共振相结合，测量了Ge晶体的毫米波吸收光谱。发现了吸收带，峰值位于5 cm^&lt；-1。从光谱强度对温度的依赖关系来看，吸收带是由Ge的双声子差过程引起的。通过目前的研究，首次证明SR是一种在高于2.5 cm；-1的毫米波能量范围内非常有用的光源。如果我们只对毫米波光子采用更灵敏的探测器，如液体He^3冷却气压计，那么SR的毫米波光谱将可以在整个毫米波范围内使用。

Millimeter wave spectroscopic study was done by using secnrotron dadiation (SR) at the UVSOR, the electron storage ring facilities of the Institute for Molecular Science (Okazaki), as a very bright light source.First of all, the optical system which has been dedicated to the far infrared spectroscopy was modified so that it became available for the millimeter wave spectroscopy. Using the revised optical system combined with the SR, a millimeter wave absorption spectrum of Ge crystal was measured. Absorption band with a peak at 5cm^<-1> was found. From the temperature dependence of the spectral intensity, the absorption band was found to be due to the two phonon difference process of Ge. By the present research, the SR was first proved to be a very useful light source in the millimeter wave energy region higher than 2.5cm^<-1>.If we adopt a more sensitive detector only to a millimeter wave photon like a liquid He^3-cooled barometer, then millimeter wave spectroscopy by the SR will become available in a whole millimeter wave region.