Transverse rectification of disorder-induced fluctuations in a driven system

ALEJANDRO B. KOLTON

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

The American Physical Society

Lugar: USA; Año: 2007 vol. 75 p. 20201 - 20205

0163-1829

We study numerically the overdamped motion of particles driven in a two-dimensional ratchet potential. In the proposed design, of the so-called geometrical-ratchet type, the mean velocity of a single particle in response to a constant force has a transverse component that can be induced by the presence of thermal or other unbiased fluctuations. We find that additional quenched disorder can strongly enhance the transverse drift at low temperatures, in spite of reducing the transverse mobility. We show that, under general conditions, the rectified transverse velocity of a driven particle fluid is equivalent to the response of a one-dimensional flashing ratchet working at a drive-dependent effective temperature, defined through generalized Einstein relations.