Development of an UHV-infrared microscope and its application to solid state physics

研制了一种工作在红外至近红外波段的超高真空红外显微镜。“在特高压”一词的含义是红外显微镜的所有功能都安装在特高压室中，并通过远程控制在室外完全工作。一般来说，红外显微镜需要我们根据红外到近红外的光谱区域，频繁地更换不同种类的合适的光学窗口。在UHV显微镜中，我们只使用一个薄的金刚石窗，它在整个波长区域几乎是透明的，以便将显微镜的内部与外界隔绝。然后，我们不需要改变光学窗口，因为显微镜的所有硬件都安装在一个特高压室。利用新型红外显微镜，我们进行了以下实验：高压下冰中质子构型有序-无序相变的红外光谱研究。在高达8 gpa的高压红外反射测量中，我们发现了一些新的吸收峰。CuIr_2Se_4是一种有趣的材料，在5 GPa左右的高压下，它表现出从金属到绝缘体的物理性质的交叉。我们在高达10 GPa的高压下进行了红外光谱显微镜测量，发现与电子相变相对应的电子态发生了明显的变化。红外光谱显微测量表明gdru_4p_ <12>是其中一种填充的方钨矿化合物，在22K以下呈反铁磁有序。GdRu_4P_<12>需要红外光谱显微镜测量，因为它在样品的不同局部位置表现出不同的物理性质。我们进行了反射测量，并明确了由于磁有序引起的光谱变化。

We have developed a new type of infrared microscope in ultra high vacuum (UHV), which works in the infrared to near infrared regions. The meaning of the term "in UHV" is that the all function of infrared microscope is installed in the UHV chamber and it works fully in operation by remote control out of the chamber. In general, infrared microscope requires us to change frequently the different kinds of suitable optical windows according to the spectroscopic regions in the infrared to near infrared. In a UHV microscope, we use only a thin diamond window, which is almost transparent in the whole wavelength region in order to seal the inner part of the microscope from the outside. Then, we don't need do any change of the optical window because all hardware of the microscope is installed in a UHV chamber. By use of new type of infrared microscope, we performed following subjects ;1.Study on the infrared spectrum due to the order-disorder phase transition of proton configuration in ice under high pressure.We found some new absorption peaks in the infrared reflection measurement under high pressure up to 8 GPa.2.Study on a change in the electronic state of CuIr_2Se_4 at high pressureCuIr_2Se_4 is known as an interesting material, which shows the crossover in physical properties from metal to insulator under high pressure around 5 GPa. We performed the infrared spectromicropscopic measurement under high pressure up to 10 GPa and found a clear change in the electronic state corresponding to the electronic phase transition.3.Infrared spectromicropscopic measurementGdRu_4P_<12> is one of the filled skutterudite compounds and shows an antiferromagnetic ordering below 22K. GdRu_4P_<12> requires an infrared spectromicropscopic measurement because it shows different physical properties at different local positions of the sample. We performed reflection measurement and clear change in the spectra due to the magnetic ordering.