Brownian ratchets driven by flashing noise strength

The stochastic transport driven by flashing multi-noise sources in a ratche t is studied. The stationary current versus the noise strength and the colo red noise correlated time T is obtained. At a fixed flip rate and strength of the colored noises, the novel phenomenon of the current reversal occurs as T reaches a certain value. More than one reversal point exists when a fl ashing colored noise source and a flashing white noise source are simultane ously taken into account.