Synchrotron X-ray spectroscopy study on the valence state and magnetization in α-YbAl1-xFexB4 (x = 0.115) at low temperatures and high magnetic fields

International Conference on Strongly Correlated Electron Systems 2014

Terashima, T.^1 ; Matsuda, Y.H.^1 ; Kuga, K.^1 ; Suzuki, S.^1 ; Matsumoto, Y.^1 ; Nakatsuji, S.^1 ; Kondo, A.^1 ; Kindo, K.^1 ; Kawamura, N.^2 ; Mizumaki, M.^2 ; Inami, T.^3

Institute for Solid State Physics (ISSP), University of Tokyo, Kashiwa

277-8581, Japan^1

SPring-8/JASRI, 1-1-1 Kouto, Sayo, Hyogo

679-5198, Japan^2

Japan Atomic Energy Agency, Sayo, Hyogo

679-5148, Japan^3

关键词: High magnetic fields;    Isostructural polymorphs;    Magnetization curves;    Mixed valence state;    Quantum criticality;    Rare earth intermetallic compounds;    Valence fluctuations;    Valence transitions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/592/1/012020/pdf
DOI  :  10.1088/1742-6596/592/1/012020

来源: IOP

【 摘 要 】

Valence fluctuation phenomena in rare-earth intermetallic compounds have attracted attention because the quantum criticality of the valence transition has been proposed theoretically. Recently, it was found that β-YbAlB4shows quantum criticality without tuning and has a strong mixed-valence state. In this study, we measured the magnetization curve and X-ray magnetoabsorption in α-YbAl1-xFexB4(x= 0.115), which is a locally isostructural polymorph of β-YbAlB4. The magnetization and X-ray experiments were performed in fields up to 55 and 40 T, respectively. A small increase in the Yb valence was observed at fields where the magnetization curve exhibited a change in slope.