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arXiv · 1805.02949

Effects of Lifshitz transitions in ferromagnetic superconductors: the case of URhGe

Yury Sherkunov·Andrey V. Chubukov·Joseph J. Betouras
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Abstract

In ferromagnetic superconductors, like URhGe, superconductivity co-exists with magnetism near zero field, but then re-appears again in a finite field range, where the system also displays mass enhancement in the normal state. We present theoretical understanding of this non-monotonic behavior. We explore the multi-band nature of URhGe and associate re-entrant superconductivity and mass enhancement with the finite field Lifshitz transition in one of the bands. We found good agreement between our theory and a number of experimental results for URhGe, such as weakly first order reentrant transition, the dependence of superconducting $T_c$ on a magnetic field, and the field dependence of the effective mass, the specific heat and the resistivity in the normal state. Our theory can be applied to other ferromagnetic multi-band superconductors.

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Yury Sherkunov, Andrey V. Chubukov, Joseph J. Betouras. 2018-05-08. Effects of Lifshitz transitions in ferromagnetic superconductors: the case of URhGe. https://doi.org/10.1103/physrevlett.121.097001

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