Y-89 NMR PROBE OF ZN INDUCED LOCAL MOMENTS IN YBA2(CU1-YZNY)3O6+X

We report the observation of resolved Y-89 NMR lines due to Zn nearest neighbors (nn) in YBa2(Cu1-yZny)3O6.64. Comparison of the Curie dependence of their frequency shifts with susceptibility data allows us to conclude that the Zn induced local moments reside on the nn Cu orbitals and to explain the absence of resolvable nn lines for x = 1. Analysis of the magnitude of the long-range spin-density oscillations monitored by the Y-89 NMR width indicates that the reduction of T(c) might be connected with magnetic effects. For x=0.64, the low T increase of the spin-lattice relaxation rate of Y-89 nuclei near Zn is shown to be governed by the local moment dynamic susceptibility.