DIFFUSION CURRENT FOR A SYSTEM IN A PERIODIC POTENTIAL DRIVEN BY MULTIPLICATIVE COLORED NOISE

The steady current for an overdamped ratchetlike system with a multipl icative exponentially correlated colored noise is obtained by solving an appropriate two-variable Fokker-Planck equation in terms of the mat rix continued-fraction method. We compare the present results with the established ones in two cases: for weak additive colored noise and a multiplicative white noise source. The dependences of the current on t he shape of the potential, the correlation time and the strength of th e noise are discussed.