sup 73^Ge-Nuclear Magnetic Resonance/Nuclear Quadrupole Resonance Investigation of Magnetic Properties of URhGe

We report on the ...Ge-nuclear magnetic resonance (NMR)/nuclear quadrupole resonance (NQR) results for the ferromagnetic (FM) superconductor URhGe. The magnitude and direction of the internal field, H..., and the parameters of the electric field gradient at the Ge site were determined experimentally. By using powdered polycrystalline samples oriented by different methods, the field dependences of NMR shift and nuclear spin relaxation rates for H... || c (easy axis) and H... || b were obtained. From the NMR shifts for H... || b, we confirmed a gradual suppression of the Curie temperature and observed a phase separation near the spin reorientation. The observation of the phase separation gives microscopic evidence that the spin reorientation under H... || b is of first order at low temperatures. The nuclear spin-lattice relaxation rate 1/T... indicates that the magnetic fluctuations are suppressed for H... || c, whereas the fluctuations remain strongly for H... || b. The enhancements of both 1/T1T and the nuclear spin-spin relaxation rate 1/T... for H... || b toward the spin reorientation field suggest that the field-induced superconductivity in URhGe emerges under the magnetic fluctuations along the b- and c-axes. (ProQuest: ... denotes formulae/symbols omitted.)