Collective Hall current in chiral active fluids: Coupling of phase and mass transport through traveling bands

• 成果类型: Article
• 署名作者: Siebers, Frank; Bebon, Robin; Jayaram, Ashreya; Speck, Thomas
• 署名单位: Johannes Gutenberg University of Mainz; University of Stuttgart
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-10671
• DOI: 10.1073/pnas.2320256121
• 发表日期: 2024-07-02
• 关键词: motion; chemotaxis; DYNAMICS

摘要

Active fluids composed of constituents that are constantly driven away from thermal equilibrium can support spontaneous currents and can be engineered to have unconventional transport properties. Here, we report the emergence of (meta)stable traveling bands in computer simulations of aligning circle swimmers. These bands are different from polar flocks and, through coupling phase with mass transport, induce a bulk particle current with a component perpendicular to the propagation direction, thus giving rise to a collective Hall (or Magnus) effect. Traveling bands require sufficiently small orbits and undergo a discontinuous transition into a synchronized state with transient polar clusters for large orbital radii. Within a minimal hydrodynamic theory, we show that the bands can be understood as nondispersive soliton solutions fully accounting for the numerically observed properties.