XMCD measurements under pressure confirm ferromagnetism in YbCu2Si2 but find none in YbRh2Si2

International Conference on Strongly Correlated Electron Systems 2014

Ramos, S.M.^1,4 ; Hering, E.N.^1,4 ; Lapertot, G.^1 ; Wilhelm, F.^2 ; Rogalev, A.^2 ; Baudelet, F.^3 ; Braithwaite, D.^1,4

University Grenoble Alpes, INAC-SPSMS, Grenoble

F-38000, France^1

European Synchrotron Radiation Facility (ESRF), CS40220, Grenoble Cedex 9

38043, France^2

Synchrotron SOLEIL, LOrme des Merisiers, St Aubin BP48, Gif-sur-Yvette cedex

91192, France^3

CEA, INAC-SPSMS, Grenoble

F-38000, France^4

关键词: High pressure;    Low pressures;    Magnetic orders;    Ordered phase;    YbRh2Si2;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/592/1/012015/pdf
DOI  :  10.1088/1742-6596/592/1/012015

来源: IOP

【 摘 要 】

YbCu2Si2and YbRh2Si2have a similar phase diagram above 8GPa. While YbCu2Si2is a well-known valence fluctuating compound that orders probably ferromagnetically above Pc=8GPa, in YbRh2Si2the nature of the magnetic order at high pressure remains unclear. However, the fact that ferromagnetic (FM) fluctuations are found at low pressure leads to a robust speculation that the high pressure order could be FM. In this work, we have investigated the magnetic order induced by pressure in both compounds, by means of XMCD spectroscopy. Our measurements have confirmed the ferromagnetism in YbCu2Si2through a clear saturation in the magnetization for pressures above Pc. On the other hand, the XMCD signal for YbRh2Si2remains weak even at 25 GPa, pointing out a clear difference between the high pressure ordered phase of these compounds, and suggesting that FM order is unlikely if not completely excluded.