Anomalous diffusion and enhancement of diffusion in a vibrational motor

The diffusion properties of a vibrational motor, in which an additional time-dependent driving brings the system out of equilibrium and the other time-periodic driving fills the role usually played by noise, are investigated. Within the tailored parameter regime, the diffusion coefficient evolving after a considerably long time develops a sharp peak closely related to the inflection points of the mean velocity upon an increase of the damping constant. The diffusion peak here depends on the super diffusion motion of the particle. Also, negative velocity (for a positive bias) depending on the subdiffusive motion, i.e. dispersionless transport in the asymptotic long time limit, is obtained. Moreover, an enhancement of diffusion phenomenon can be observed. These results may be helpful for separating particles under some conditions by adjusting the external forces applied.