Statistically Locked-in Transport Through Periodic Potential Landscapes

TL;DR

This paper investigates how particles move through periodic landscapes, revealing a complex hierarchy of trajectories that are statistically, but not deterministically, locked-in, and introduces a model capturing this behavior.

Contribution

It presents a new idealized model that explains the statistical locking-in phenomena observed in experiments with particles in modulated landscapes.

Findings

Particles exhibit a hierarchy of commensurate trajectories.

Trajectories are statistically locked-in rather than strictly deterministic.

The model captures both the structure and randomness of observed states.

Abstract

Classical particles driven through periodically modulated potential energy landscapes are predicted to follow a Devil's staircase hierarchy of commensurate trajectories depending on the orientation of the driving force. Recent experiments on colloidal spheres flowing through arrays of optical traps do indeed reveal such a hierarchy,but not with the predicted structure. The microscopic trajectories, moreover,appear to be random, with commensurability emerging only in a statistical sense. We introduce an idealized model for periodically modulated transport in the presence of randomness that captures both the structure and statistics of such statistically locked-in states.