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arXiv · 0808.2500

Field Re-entrant Superconductivity Induced by the Enhancement of Effective Mass in URhGe

Atsushi Miyake·Dai Aoki·Jacques Flouquet
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Abstract

High quality single crystals of a ferromagnetic superconductor URhGe were successfully grown. The electrical resistivity was measured for the field along b-axis in the orthorhombic crystal structure in order to study precisely its field re-entrant superconductivity which occurs in the vicinity of the field $H_{\rm R}$, where the easy magnetization switches from $c$ to b-axis. The field re-entrant superconductivity of URhGe is analyzed with special focus on its dependence with the value of residual resistivity $ρ_0$ and the coefficient $A$ of $T^2$ term of the resistivity. The experimental results are well explained by a crude model related with the field dependence of the effective mass $m^\ast$, where the corresponding critical temperature $T_{\mathrm{sc}}(m^\ast)$ and the upper critical field $H_{\rm c2}$ are strongly enhanced. Discussion is made on the interplay between magnetic and superconducting phase diagram as well as the link between $T_{\mathrm{sc}}$ and $A$ in other heavy fermion superconductors.

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Atsushi Miyake, Dai Aoki, Jacques Flouquet. 2008-08-18. Field Re-entrant Superconductivity Induced by the Enhancement of Effective Mass in URhGe. https://doi.org/10.1143/jpsj.77.094709

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