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arXiv · 1412.7879

Topological properties and the dynamical crossover from mixed-valence to Kondo-lattice behavior in golden phase of SmS

Chang-Jong Kang·Hong Chul Choi·Kyoo Kim·B. I. Min
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Abstract

We have investigated temperature-dependent behaviors of electronic structure and resistivity in a mixed-valent golden phase of SmS, based on the dynamical mean-field theory band structure calculations. Upon cooling, the coherent Sm 4$f$ bands are formed to produce the hybridization induced pseudogap near the Fermi level, and accordingly the topology of Fermi surface is changed to exhibit a Lifshitz-like transition. The surface states emerging in the bulk gap region are found to be not topologically protected states but just typical Rashba spin-polarized states, indicating that SmS is not a topological Kondo semimetal. From the analysis of anomalous resistivity behavior in SmS, we have identified universal energy scales, which characterize the Kondo/mixed-valent semimetallic systems.

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Chang-Jong Kang, Hong Chul Choi, Kyoo Kim, B. I. Min. 2014-12-26. Topological properties and the dynamical crossover from mixed-valence to Kondo-lattice behavior in golden phase of SmS. https://doi.org/10.1103/physrevlett.114.166404

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