Journal of Statistical Physics, Vol. 70, Nos, 1/2, 1993. p. 247-256.
A stochastic model, proposed first by Landauer and Biittiker 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 a stochastic resonance mechanism in solid-state physics.