Discontinuous Transition from a Real Bound State to Virtual Bound State in a Mixed-Valence State of SmS

作者：Imura Keiichiro^*; Kanematsu Shinkichi; Matsubayashi Kazuyuki; Suzuki Hiroyuki S; Deguchi Kazuhiko; Sato Noriaki K

来源：Journal of the Physical Society of Japan, 2011, 80(11): 113704.

DOI：10.1143/JPSJ.80.113704

• SmS
• mixed-valence system
• valence transition
• high-pressure experiments

Golden SmS is a paramagnetic, mixed-valence system with a pseudogap. With increasing pressure across a critical pressure P-c, the system undergoes a discontinuous transition into a metallic, anti-ferromagnetically ordered state. By using a combination of thermodynamic, transport, and magnetic measurements, we show that the pseudogap results from the formation of a local bound state with spin singlet. We further argue that the transition P-c is regarded as a transition from an insulating electron-hole gas to a Kondo metal, i.e., from a spatially bound state to a Kondo virtually bound state between 4f and conduction electrons.

• 出版日期2011-11