Infrared studies of f electron systems under high pressure using synchrotron radiation

Infrared spectroscopic studies of various rare-earth compounds (f electron systems) have been made under high pressure, in order to probe their interesting electronic structures induced by pressure. High pressures have been generated with the use of diamond anvil cells (DAC's). To precisely perform IR reflectivity measurements of single crystal samples mounted in a DAC, the synchrotron radiation at SPring-8 has been used as a highly bright IR source. In this manuscript, the basic concept of the high pressure IR experiment using synchrotron radiation is introduced, and an example of obtained data for YbS and their physical interpretation are briefly discussed.