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arXiv · 1806.08250

Current reversal in interacting colloids under time-periodic drive

Shubhashis Rana·Sanchari Goswami·Sakuntala Chatterjee·Punyabrata Pradhan
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Abstract

Using molecular dynamics simulations, we study particle-transport in a system of interacting colloidal particles on a ring, where the system is driven by a time-dependent external potential, moving along the ring. We consider two driving protocols: (i) the external potential barrier moves with a uniform velocity $v$ along the ring, and (ii) it moves in discrete jumps with jump-length $l$ and waiting time $τ$ with an effective velocity $v=l/τ$. The time-averaged (dc) particle current, which always remains positive in case (i), interestingly reverses its direction in case (ii) upon tuning the particle-number density $ρ_0$ and the effective barrier velocity $v$. We also find a scaling form for the current in terms of number density, barrier velocity, barrier height and temperature of the system.

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Shubhashis Rana, Sanchari Goswami, Sakuntala Chatterjee, Punyabrata Pradhan. 2018-12-05. Current reversal in interacting colloids under time-periodic drive. https://doi.org/10.1103/physreve.98.052142

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