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arXiv · 0803.0352

Strong spin-orbit coupling effects on the Fermi surface of Sr2RuO4 and Sr2RhO4

Abstract

We present a first-principle study of spin-orbit coupling effects on the Fermi surface of Sr2RuO4 and Sr2RhO4. For nearly degenerate bands, spin-orbit coupling leads to a dramatic change of the Fermi surface with respect to non-relativistic calculations; as evidenced by the comparison with experiments on Sr2RhO4, it cannot be disregarded. For Sr2RuO4, the Fermi surface modifications are more subtle but equally dramatic in the detail: spin-orbit coupling induces a strong momentum dependence, normal to the RuO2 planes, for both orbital and spin character of the low-energy electronic states. These findings have profound implications for the understanding of unconventional superconductivity in Sr2RuO4.

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M. W. Haverkort, I. S. Elfimov, L. H. Tjeng, G. A. Sawatzky, A. Damascelli. 2008-03-03. Strong spin-orbit coupling effects on the Fermi surface of Sr2RuO4 and Sr2RhO4. https://doi.org/10.1103/physrevlett.101.026406

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