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arXiv · 0904.0532

Muon spin rotation and relaxation in the superconducting ferromagnet UCoGe

A. de Visser·N. T. Huy·A. Gasparini·D. E. de Nijs·D. Andreica·C. Baines·A. Amato
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Abstract

We report zero-field muon spin rotation and relaxation measurements on the superconducting ferromagnet UCoGe. Weak itinerant ferromagnetic order is detected by a spontaneous muon spin precession frequency below the Curie temperature $T_C = 3$ K. The $\mu^+$ precession frequency persists below the bulk superconducting transition temperature $T_{sc} = 0.5$ K, where it measures a local magnetic field $B_{loc} = 0.015$ T. The amplitude of the $\mu$SR signal provides unambiguous proof for ferromagnetism present in the whole sample volume. We conclude ferromagnetism coexists with superconductivity on the microscopic scale.

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A. de Visser, N. T. Huy, A. Gasparini, D. E. de Nijs, D. Andreica, C. Baines, A. Amato. 2009-04-03. Muon spin rotation and relaxation in the superconducting ferromagnet UCoGe. https://doi.org/10.1103/physrevlett.102.167003

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