Diagnosis of quantum criticality by nuclear spin-echo decay method

Kambe, Shinsaku  ; Sakai, Hironori   ; Tokunaga, Yo  ; Chudo, Hiroyuki ; Walstedt, R. E.*

In order to diagnose the quantum critical behaviour in heavy fermion systems, the Gaussian spin-spin relaxation time determined by NMR spin-echo decay measurements is found to be useful. Combined with the spin-lattice relaxation time , an exponent of quantity is predicted to be sensitive to the type of quantum criticality. In fact in heavy fermion USn near the quantum critical point, is found to be constant as expected for the -SDW magnetic instability.