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 HR, 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 ρ0 and the coefficient A of T2 term of the resistivity. The experimental results are well explained by a crude model related with the field dependence of the effective mass m*, where the corresponding critical temperature T sc(m*) and the upper critical field Hc2 are strongly enhanced. Discussion is made on the interplay between magnetic and superconducting phase diagram as well as the link between Tsc and A in other heavy fermion superconductors.
- Effective mass
- Ferromagnetic superconductor
- Field re-entrant superconductivity