We report the temperature dependence of the Yb valence in the geometrically frustrated compound
The temperaturedependent evolution of the Kondo lattice is a longstanding topic of theoretical and experimental investigation and yet it lacks a truly microscopic description of the relation of the basic fc hybridization processes to the fundamental temperature scales of Kondo screening and Fermiliquid lattice coherence. Here, the temperature dependence of fc hybridized band dispersions and Fermienergy f spectral weight in the Kondo lattice system CeCoIn_{5}is investigated using fresonant angleresolved photoemission spectroscopy (ARPES) with sufficient detail to allow direct comparison to firstprinciples dynamical meanfield theory (DMFT) calculations containing full realism of crystalline electricfield states. The ARPES results, for two orthogonal (001) and (100) cleaved surfaces and three different fc hybridization configurations, with additional microscopic insight provided by DMFT, reveal f participation in the Fermi surface at temperatures much higher than the lattice coherence temperature,
 Award ID(s):
 1810310
 NSFPAR ID:
 10190686
 Publisher / Repository:
 Proceedings of the National Academy of Sciences
 Date Published:
 Journal Name:
 Proceedings of the National Academy of Sciences
 Volume:
 117
 Issue:
 38
 ISSN:
 00278424
 Page Range / eLocation ID:
 p. 2346723476
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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