NMR study of ferromagnetic superconductor URhGe under uniaxial stress

Tokunaga, Yo  ; Aoki, Dai*; Braithwaite, D.*; Knebel, G.*; Brison, J.-P.*; Pourret, A.*; Lapertot, G.*; Niu, Q.*; Valiska, M.*; Flouquet, J.*; Sakai, Hironori   ; Kambe, Shinsaku  

Recently, uniaxial stress has been found to be a remarkable tool for tuning the pairing strength in a ferromagnetic superconductor URhGe. A relatively small uniaxial stress applied along the crystal axis changes the superconducting (SC) phase diagram significantly, merging the low-field SC and reentrant SC domes, with a large enhancement of . The increases both at zero field and under a field, reaching 1 K, more than twice higher than at ambient pressure. This enhancement of SC has been shown to be directly related to a change of the magnetic dimensionality, moving the system away from the Ising-type limit, which results in the rapid decrease of the . In this study, by means of zero-field Ge NMR in the ferromagnetic state, we have investigated the effects of uniaxial stress on the electronic state of URhGe.