Intermediate valence state in YbB4 revealed by resonant x-ray emission spectroscopy. (24th August 2022)

• Record Type: Journal Article
• Authors: Frontini, Felix; Lebert, Blair W; Cho, K K; Song, M S; Cho, B K; Pollock, Christopher J; Kim, Young-June
• Is Part Of: Journal of physics. Volume 34:Number 34(2022)
• Publication Date: 2022-08-24
• Subjects: Kondo physics -- intermediate valence -- frustrated magnetism -- x-ray spectroscopy; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac7629
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We report the temperature dependence of the Yb valence in the geometrically frustrated compound Y b B 4 from 12 to 300 K using resonant x-ray emission spectroscopy at the Yb L α 1 transition. We find that the Yb valence, v, is hybridized between the v = 2 and v = 3 valence states, increasing from v = 2.61 ± 0.01 at 12 K to v = 2.67 ± 0.01 at 300 K, confirming that Y b B 4 is a Kondo system in the intermediate valence regime. This result indicates that the Kondo interaction in Y b B 4 is substantial, and is likely to be the reason why Y b B 4 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 scale T v .