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arXiv · 0807.3726

The high-field Fermi surface of YbRh2Si2

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

We present quantum oscillation measurements of YbRh2Si2 at magnetic fields above the Kondo-suppression scale H0 ~ 10 T. Comparison with electronic structure calculations is complicated because the "small" Fermi surface, where the Yb 4f-quasi-hole is not contributing to the Fermi volume, and "large" Fermi surface, where the Yb 4f-quasi-hole is contributing to the Fermi volume, are related by a rigid Fermi energy shift. This means that spin-split branches of the large Fermi surface can look like unsplit branches of the small surface, and vice-versa. Thus, although the high-field angle dependence of the experimentally-measured oscillation frequencies most resembles the electronic structure prediction for the small Fermi surface, this may instead be a branch of the spin-split large Fermi surface.

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P. M. C. Rourke, A. McCollam, G. Lapertot, G. Knebel, J. Flouquet, S. R. Julian. 2008-07-23. The high-field Fermi surface of YbRh2Si2. https://doi.org/10.1088/1742-6596/150/4/042165

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