THE CURRENT CHARACTERISTICS OF TWO-STATE FLASHING RATCHETS COMPOSED OF TWO ASYMMETRIC POTENTIALS

The transport of Brownian particles in two-state flashing ratchets composed of two asymmetric potentials with the same period is investigated. The analytic expression of a probability current is derived by using the power series expansion method and used to generate the curve characteristics of the current varying with other parameters. The effects of the asymmetric parameters and heights of two potentials and the transition rates between two states on the probability current are discussed in detail. The influence of other parameters on the behaviors of the current is also analyzed. It is found that the current is affected by not only the asymmetric parameters and heights of two potentials but also the transition rates between two states. It is also found that the heights of two potentials may change the magnitude as well as the direction of the current when the transition rates between two states are not the same. It is expected that the results obtained here may be observed in some physical and biological systems.