Abstract
Experimental details are given for NMR and NQR measurements of nuclear-spin-lattice relaxation rates for the planar copper and oxygen sites in . Enrichment of samples with , alignment of powder samples, elimination of artifacts in relaxation-rate measurements, and the unusual aspects of weak magnetic-field experiments used to overcome an observed magnetic-field dependence in the rates are described. The role of fluxoids in the magnetic-field dependence of the relaxation rates is discussed. The relaxation rate data are shown to be inconsistent with a spin-singlet, orbital s-wave pairing state with an isotropic energy gap.
- Received 25 July 1994
DOI:https://doi.org/10.1103/PhysRevB.50.13645
©1994 American Physical Society