Static and dynamic Cu NMR tensors ofYBa2Cu3O7−δ

Abstract

The authors report single-crystal Cu NMR data for $\mathrm{Y}{\mathrm{Ba}}_2{\mathrm{Cu}}_3{\mathrm{O}}_{7-\delta }$ ($T_c=90\mathrm{}$ K). The shift tensor $K_{\alpha \alpha }$ ($\alpha =a, b, c$), the electric-field-gradient tensor ${\nu }_{\alpha \alpha }$, and the spin-lattice-relaxation-rate tensor are reported for Cu atoms in the planes and chains. The authors show that a model in which both chain and plane Cu are approximated as ${\mathrm{Cu}}^{2+}$ ions with a net spin account for the field-gradient tensor and the shift tensor at both chain and plane sites, and for the relaxation rate at the plane sites.