Dichotomous noise-induced negative mass and mobility of inertial Brownian particle

Abstract

We consider an inertial Brownian particle moving in a symmetric periodic potential which is subjected to an unbiased time-periodic force combined with a constant static force and the fluctuant generated by a dichotomous noise. For the deterministic case, there are multiple current reversals as the mass increases, which would imply the phenomena of negative mass and mobility. A physical explanation of these phenomena is derived from basins of attraction. For the case of an additional random mass, the results show that the system may be very sensitive to a small change of the strength of dichotomous noise. An increase of the strength of dichotomous noise leads not only to significant decrease of the intervals of negative mass but also to shrinking the regions of negative mobility or even vanishing it. The probability distribution of the Brownian particle’ velocity is used to interpret the underlying mechanisms. We also study diffusion corresponding to these mobilities in the system. It is found that the negative mass and mobility can strengthen the diffusion. Our findings may extensively exist in physical, chemical, and material fields, which provides a way to manipulate the mobility of Brownian particle by altering the strength of dichotomous noise.