Synchronized first-passages in a double-well system driven by an asymmetric periodic field

Abstract

We perform a Langevin dynamic numerical simulation of a double-well potential system subjected to an asymmetric sawtooth type external time varying field and white noise forces. The hysteresis loss calculated from the first-passage time distribution obtained shows an asymmetric behaviour with respect to the asymmetry in the field sweep. The hysteresis loss in our model being a measure of the synchronized passages from one well to the other, indicates asymmetric “correlated” passages in the two opposing directions when driven by a temporally asymmetric external field in the presence of white noise (fluctuating) forces. The implication of our results for the phenomenon of a predominantly unidirectional motion of a Brownian particle in a symmetric periodic (non-ratchet-like) potential is discussed.