Reaction Delays Boost, Rectify, and Reverse Motility in Activity Landscapes

2026/08/04 by Constantin Rein, Klaus Kroy, Viktor Holubec
Physics and Astronomy · #cond-mat.soft #physics.bio-ph

paper · pdf

5 pages, 2 figures

arxiv created 2026/08/04 · arxiv updated 2026/08/05

Abstract

Local detailed balance restricts transport by self-propulsion in static activity landscapes. We show that a delayed speed adaptation (``delayed motility/kinesis'') generically breaks this symme try, inducing directed transport in asymmetric periodic motility profiles and enhancing diffusion in symmetric ones. Both effects occur for run-and-tumble, active Brownian, and inertial active particles, without requiring potential interactions, walls, imposed gradients, higher dimensions, or translational diffusion. Their magnitudes, and even current reversals, are conveniently tuned via the delay time, which establishes delayed motility as a versatile generic and experimentally accessible mechanism for autonomous self-steering and transport control in motile-active-matter circuity.

Citations

• Density modulations in active colloidal systems through orthogonal propulsion control and sensory delays
• Delayed Active Swimmer in a Velocity Landscape
• Engineering sensorial delay to control phototaxis and emergent collective behaviors
• Light-induced self-assembly of active rectification devices
• When are active Brownian particles and run-and-tumble particles equivalent? Consequences for motility-induced phase separation