Temperature and friction-induced tunable current reversal, anomalous mobility and diffusions

We numerically investigate the transport properties and dynamic relaxation of a classical inertia Brownian particle in a biased periodic potential under the action of friction and thermal fluctuations. The both fluctuations may be related to friction, thus they may be correlated with each other. We mainly focus on how particle’s transport and dynamic relaxation are affected by fluctuations and the correlation between them. It is unexpected that the combinations of them can tune transport of the particle, including current reversal, and anomalous mobility and diffusions. These results are explained via the stationary probability distributions, which suggest that the bias of the potential can lead to a transition between unimodal and bimodal stationary probability distributions of particle’s velocity. To understand the physical mechanism of these findings, we present dynamic relaxations, namely, the transient probability distributions of velocity and position. These distributions suggest that the motion of the particle is not only related to systematic parameters, but also sensitive to the initial conditions. Our findings may be potentially helpful for research on various transport of the particle and on similar circuits, such as particle separation, Josephson junctions, the phase-locked loops, etc.