Anisotropic spin fluctuations and superconductivity in "115" heavy fermion compounds; Co NMR study in PuCoGa

Baek, S.-H.*; Sakai, Hironori; Bauer, E. D.*; Mitchell, J. N.*; Kennison, J. A.*; Ronning, F.*; Thompson, J. D.*

Physical Review Letters, 105(21), p.217002_1 - 217002_4, 2010/11

https://doi.org/10.1103/PhysRevLett.105.217002

We report results of Co nuclear magnetic resonance measurements on a single crystal of superconducting PuCoGa in its normal state. The nuclear spin-lattice relaxation rates and the Knight shifts as a function of temperature reveal an anisotropy of spin fluctuations with finite wave vector . By comparison with the isostructural members, we conclude that antiferromagnetic -type anisotropy of spin fluctuations plays an important role in mediating superconductivity in these heavy fermion materials.