Dimensional coupling induced current reversal in two-dimensional driven lattices

TL;DR

This paper demonstrates that in two-dimensional ac-driven lattices, the particle transport direction can be dynamically reversed by altering the lattice structure perpendicular to the driving force, due to dimensional coupling effects.

Contribution

It introduces a novel mechanism where lattice structure changes induce current reversal via dimensional coupling, applicable to cold atom optical lattices.

Findings

Current reversal depends on lattice structure modifications.

Dimensional coupling enables exploration of new phase space regions.

Timescale of reversals is governed by coupling strength.

Abstract

We show that the direction of directed particle transport in a two dimensional ac-driven lattice can be dynamically reversed by changing the structure of the lattice in the direction perpendicular to the applied driving force. These structural changes introduce dimensional coupling effects, the strength of which governs the timescale of the current reversals. The underlying mechanism is based on the fact that dimensional coupling allows the particles to explore regions of phase space which are inaccessible otherwise. The experimental realization for cold atoms in ac-driven optical lattices is discussed.