Nuclear magnetic resonance in dilute magnetic alloys and superconductors

Abstract

The longitudinal and transverse spin-lattice relaxation rates for paramagnetic ion-nuclei in dilute Kondo systems are calculated. It is shown that observation of the Kondo anomalies in the NMR parameters is facilitated by either high temperatures (kT ≫ ω-s$/, the resonance frequency for localized moments) or low temperatures (kT ≪ ω-s$/). The longitudinal spin-lattice relaxation of paramagnetic ion-nuclei in 'dirty' type II superconductors is investigated. The influence of the order parameter fluctuations on relaxation of paramagnetic ion-nuclei in type II superconductors is studied at temperatures slightly above the transition temperature Tc.