Particle Transport in a Confined Ratchet Driven by the Colored Noise

Abstract

In this paper, we study particle transport in a confined ratchet which is constructed by combining a periodic channel with a ratchet potential under colored Gaussian noise excitation. Due to the interaction of colored noise and confined ratchet, particles host remarkably different properties in the transporting process. By means of the second-order stochastic Runge-Kutta algorithm, effects of the system parameters, including the noise intensity, colored noise correlation time and ratchet potential parameters are investigated by calculating particle current. The results reveal that the colored noise correlation time can lead to an increase of particle current. The increase of noise intensity along the horizontal or vertical direction can accelerate the particle transport in the corresponding direction but slow down the particle transport when there are the same noise intensities in both directions. For potential parameters, an increase of the slope parameter results into an increase of particle currents. The interactions of potential parameters and correlation time can induce complex particle transport phenomena, i.e. particle current increases with the increase of the potential depth parameter for a smaller asymmetric parameter and non-zero correlation time, while the tendency changes for a larger asymmetric parameter. Accordingly, suitable system parameters can be chosen to accelerate the particle transport and used to design new devices for particle transport in microscale.