CREATION OF NOVEL F-ELECTRON STATE BY HIGH PRESSURE AND ITS DIRECT OBSERVATION BY INFRARED SPECTROSCOPY

本研究项目的目的是利用红外光谱技术研究高压下在所谓的重费米子化合物中实现的电导-F电子杂化电子态。为了对安装在压力发生室（金刚石砧室）中的小样品进行困难的红外光谱分析，在SPRING-8的束线BL 43 IR上使用了高亮度同步辐射作为红外源。本文研究了YbA_3、YbS、Yb、CeRu_4Sb_3等氟电子化合物在高压下红外光谱的演化<12><12>。我们已经观察到它们的红外光谱随着外部压力的变化而发生很大的变化。我们用C-F杂化带模型解释了掺杂引起的光谱变化。我们希望在今后的工作中能进一步扩展对高压下F电子系统的研究。除了压力研究外，我们还继续了F电子系统在环境压力下的工作。我们观察到许多Ce和Yb化合物的光学电导的普遍关系。这是值得注意的，因为这样一个普遍的关系只知道他们的国家财产，被称为角胁-伍兹关系

THE AIM OF THIS RESEARCH PROJECT HAS BEEN THE STUDY OF THE CONDUCTION-F ELECTRON HYBRIDIZED ELECTRONIC STATE, REALIZED IN THE SO-CALLED HEAVY FERMION COMPOUNDS, UNDER HIGH PRESSURE USING INFRARED SPECTROSCOPY TECHNIQUE. TO CARRY OUT THE DIFFICULT INFRARED SPECTROSCOPY OF SMALL SAMPLES MOUNTED IN A PRESSURE GENERTING CELL (DIAMOND ANVIL CELL), A HIGH BRILLIANCE SYNCHROTRON RADIATION WAS USED AS AN INFRARED SOURCE AT THE BEAM LINE BL43IR OF SPRING-8. WE HAVE STUDIED THE EVOLUTION OF INFRARED SPECTRA UNDER HIGH PRESSURE FOR SUCH F ELECIRON COMPOUNDS AS YbA_<12>, YbS, ELEMENTAL Yb, AND CeRu_4Sb_<12> SO FAR. WE HAVE OBSERVED LARGE CHANGES IN THEIR INFRARED SPECTRA AS A FUNCTION OF EXTERNAL PRESSURE. WE HAVE INTERPRETED THE PRESSURE-INDUCED SPECTRAL CHANGES USING THE SO-CALLED C-F HYBRIDIZED BAND MODEL. WE PLAN TO FURTHER EXTEND OUR STUDIES OF F ELECTRON SYSTEMS UNDER HIGH PRESSURE IN THE FUTURE. IN ADDITION TO THE PRESSURE STUDIES, WE HAVE ALSO CONTINUED OUR WORK OF F ELECTRON SYSTEMS AT AMBIENT PRESSURE. WE HAVE OBSERVED A UNIVERSAL RELATION REGARDING THE OPTICAL CONDUCTIVITY OF MANY Ce AND Yb COMPOUNDS. THIS IS REMARKABLE SINCE SUCH A UNIVERSAL RELATION HAD BEEN KNOWN ONLY FOR THEIR GROUND STATE PROPETIES, KNOWN AS KADOWAKI-WOODS RELATION