ESR OF A MAGNETIC PROBE IN THE NEIGHBORHOOD OF AN ANDERSON IMPURITY

Abstract

The renormalization group formalism was applied to calculate the spin lattice relaxation rate [Formula: see text] of a magnetic probe located in the neighborhood of a spin degenerate Anderson impurity. In the Kondo regime, [Formula: see text] as a function of the temperature T presents a peak at the Kondo temperature TK. For T≪TK, the system behaves as a heavy Fermi liquid, with an enhanced density of states, which increases with the decrease in the Kondo temperature; [Formula: see text] is a universal function of T/ΓK up to temperatures of the order of 100 ΓK, where ΓK is the Kondo width for temperatures lower than TK. The spin relaxation rate [Formula: see text] is proportional to the product of the magnetic susceptibility and temperature χT. Moreover, in the peak, [Formula: see text] at the Kondo temperature decreases with the increase in the distance between the Anderson impurity and the magnetic probe.