Intermediate valence state in YbB 4 revealed by resonant x-ray emission spectroscopy
Abstract

We report the temperature dependence of the Yb valence in the geometrically frustrated compound$YbB4$from 12 to 300 K using resonant x-ray emission spectroscopy at the Yb$Lα1$transition. We find that the Yb valence,v, is hybridized between thev = 2 andv = 3 valence states, increasing from$v=2.61±0.01$at 12 K to$v=2.67±0.01$at 300 K, confirming that$YbB4$is a Kondo system in the intermediate valence regime. This result indicates that the Kondo interaction in$YbB4$is substantial, and is likely to be the reason why$YbB4$does not order magnetically at low temperature, rather than this being an effect of geometric frustration. Furthermore, the zero-point valence of the system is extracted from our data and compared with other Kondo lattice systems. The zero-point valence seems to be weakly dependent on the Kondo temperature scale, but not on the valence change temperature scaleTv.

Authors:
; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10368030
Journal Name:
Journal of Physics: Condensed Matter
Volume:
34
Issue:
34
Page Range or eLocation-ID:
Article No. 345601
ISSN:
0953-8984
Publisher:
IOP Publishing
National Science Foundation
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