Weak Disorder Strongly Improves the Selective Enhancement of Diffusion in a Tilted Periodic Potential

by Ralf Eichhorn (Nordita)

Thursday 30 Oct 2008, 15:15 → 16:15 Europe/Stockholm

122:026

The diffusion of an overdamped Brownian particle in a tilted periodic potential is known to exhibit a pronounced enhancement over the free thermal diffusion within a small interval of tilt-values. We show that weak disorder in the form of small, time-independent deviations from a strictly spatially periodic potential may further boost this diffusion peak by orders of magnitude. Our general theoretical predictions are in excellent agreement with experimental observations of a colloidal particle moving in a light-induced periodic potential.