title: Diffusion in tilted periodic potentials: Enhancement, universality, and scaling.
abstract: An exact analytical expression for the effective diffusion coefficient of an overdamped Brownian particle in a tilted periodic potential is derived for arbitrary potentials and arbitrary strengths of the thermal noise. Near the critical tilt (threshold of deterministic running solutions) a scaling behavior for weak thermal noise is revealed and various universality classes are identified. In comparison with the bare (potential-free) thermal diffusion, the effective diffusion coefficient in a critically tilted periodic potential may be, in principle, arbitrarily enhanced. For a realistic experimental setup, an enhancement by 14 orders of magnitude is predicted so that thermal diffusion should be observable on a macroscopic scale at room temperature.
authors.affiliation: Institut für Physik, Universität Augsburg, Universitätsstrasse 1, D-86135 Augsburg, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Reimann
authors.forename: C
authors.initials: C
authors.lastname: Van den Broeck
authors.forename: H
authors.initials: H
authors.lastname: Linke
authors.forename: P
authors.initials: P
authors.lastname: Hänggi
authors.forename: J M
authors.initials: JM
authors.lastname: Rubi
authors.forename: A
authors.initials: A
authors.lastname: Pérez-Madrid