Pushing run-and-tumble particles through a rugged channel

TL;DR

This paper studies run-and-tumble particles in rugged channels, revealing non-monotonic current behavior, the impact of activity on current maximization, and providing an effective theoretical model.

Contribution

It introduces a new analysis of run-and-tumble particles in complex channels, highlighting nontrivial current behaviors and developing an effective theoretical description.

Findings

Current is non-monotonic with external field.

Activity increases maximal current and delays current decay.

Zero-field density profiles are nontrivial for asymmetric obstacles.

Abstract

We analyze the case of run-and-tumble particles pushed through a rugged channel both in the continuum and on the lattice. The current characteristic is non-monotone in the external field with (1) the appearance of a current and nontrivial density profile even at zero field for asymmetric obstacles, (2) the current decreasing with persistence at small field and increasing with persistence at large field. Activity in terms of self-propulsion increases the maximal current and postpones dying. We give an effective theoretical description with wider validity.