Effect of correlated noises on Brownian motor

The Brownian motor operating between two correlated Gaussian white noises was investigated. The expressions of the current and the energy conversion efficiency of the Brownian motor were analytically derived by exploiting adiabatic approximation. The results indicates that: (i) Regulating the correlation strength λ   between the two noises and the ratio D2/D1D2/D1 of the two noise intensities can change the rotational direction of the motor; (ii) For the smaller D2/D1D2/D1, an optimal λ can make the positive current and the efficiency be maximal, and for the smaller λ  , an optimal D2/D1D2/D1 also let the positive current be maximal. The results were explained from a viewpoint of modified potentials. The study is of important significance in the aspect of controlling the operation of the Brownian motor.