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arXiv · 0807.3970

Magnetic-Field Dependence of the YbRh2Si2 Fermi Surface

P. M. C. Rourke·A. McCollam·G. Lapertot·G. Knebel·J. Flouquet·S. R. Julian
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Abstract

Magnetic-field-induced changes of the Fermi surface play a central role in theories of the exotic quantum criticality of YbRh2Si2. We have carried out de Haas-van Alphen measurements in the magnetic-field range 8 T <= H <= 16 T, and directly observe field dependence of the extremal Fermi surface areas. Our data support the theory that a low-field "large" Fermi surface, including the Yb 4f quasihole, is increasingly spin split until a majority-spin branch undergoes a Lifshitz transition and disappears at H0 ~ 10 T, without requiring 4f localization at H0.

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P. M. C. Rourke, A. McCollam, G. Lapertot, G. Knebel, J. Flouquet, S. R. Julian. 2009-02-03. Magnetic-Field Dependence of the YbRh2Si2 Fermi Surface. https://doi.org/10.1103/physrevlett.101.237205

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