Effect of external periodic regulations on Brownian motor

Abstract

Effect of external periodic regulations on a symmetric Brownian motor performing between two temperature sources was investigated. By means of numerical calculations, we found that: (i) The regulations can control magnitude and direction of the motor’s current to a large degree. As one of the motor’s compartments is regulated, the motor’s current can be both inversed and maximized, dependent on amplitude and frequency of the periodic driving force. If two periodic driving forces with identical amplitudes and frequencies are employed to regulate respectively two compartments of the Brownian motor, the current’s magnitude and direction will make periodic oscillations with phase difference between them. In addition, the external periodic regulation can also change direction of thermal rectifier of the system as a switch. (ii) Optimal regulating parameters of the external periodic forces can enhance pronouncedly conversion efficiency of energy of the Brownian motor.