Chiral Brownian Motor and Refrigerator

Martijn van den Broek, Universiteit Hasselt, Belgium

A microscopically exact analytic discussion is presented for a rotational Brownian motor of arbitrary shape driven by thermal fluctuations from two separate heath baths. The moments of the angular velocity are calculated. The role of thermal non-equilibrium and chiral asymmetry are discussed. Invoking Onsager symmetry, the same configuration can be used to transfer heat from one reservoir to another upon application of an external torque, turning the Brownian motor into a Brownian refrigerator. The orders of magnitude of these effects for a real physical realization are estimated.