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arXiv · 1211.1326

High-field moment polarization in the ferromagnetic superconductor UCoGe

W. Knafo·T. D. Matsuda·D. Aoki·F. Hardy·G. W. Scheerer·G. Ballon·M. Nardone·A. Zitouni·C. Meingast·J. Flouquet
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Abstract

We report magnetization and magnetoresistivity measurements on the isostructural ferromagnetic superconductors UCoGe and URhGe in magnetic fields up to 60 T and temperatures from 1.5 to 80 K. At low-temperature, a moment polarization in UCoGe in a field $μ_0\mathbf{H}\parallel\mathbf{b}$ of around 50 T leads to well-defined anomalies in both magnetization and magnetoresistivity. These anomalies vanish in temperatures higher than 30-40 K, where maxima in the magnetic susceptibility and the field-induced variation of the magnetoresistivity are found. A comparison is made between UCoGe and URhGe, where a moment reorientation in a magnetic field $μ_0\mathbf{H}\parallel\mathbf{b}$ of 12 T leads to field-induced reentrant superconductivity.

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W. Knafo, T. D. Matsuda, D. Aoki, F. Hardy, G. W. Scheerer, G. Ballon, M. Nardone, A. Zitouni, C. Meingast, J. Flouquet. 2012-11-12. High-field moment polarization in the ferromagnetic superconductor UCoGe. https://doi.org/10.1103/physrevb.86.184416

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