1211.1326 (W. Knafo et al.)

High-field moment polarization in the ferromagnetic superconductor
UCoGe; similarities with the URhGe-case    [PDF]

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

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 $\mu_0\mathbf{H}\parallel\mathbf{b}$ 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 $\mu_0\mathbf{H}\parallel\mathbf{b}$ of 12 T leads to field-induced reentrant superconductivity.

View original: http://arxiv.org/abs/1211.1326