Persistent currents in mesoscopic rings: A stochastic model

Abstract

A stochastic model, proposed first by Landauer and Buttiker to explain the phenomenon of persistent currents in submicrometer normal metal rings, is developed quantitatively by determining the relevant relaxation time scales. The current excited by a periodically modulated magnetic field threading the ring is computed as the sum of two clear-cut components: a persistent current and a driven current. The latter component provides a notable example of astochastic resonance mechanism in solid-state physics.