Year: 2025
Type: article
Abstract: Systems driven far from equilibrium may exhibit anomalous density fluctuations: active matter with orientational order displays giant density fluctuations at a large scale, while systems of interacting particles close to an absorbing phase transition may exhibit hyperuniformity, suppressing large-scale density fluctuations. We show that these seemingly incompatible phenomena can coexist in nematically ordered active systems, provided activity is conditioned to particle contacts. We characterize this unusual state of matter and unravel the underlying mechanisms simultaneously, leading to spatially enhanced (on large length scales) and suppressed (on intermediate length scales) density fluctuations. Our work highlights the potential for a rich phenomenology in active matter systems in which the particles' activity is triggered by their local environment, and calls for a broader exploration of absorbing phase transitions in orientationally ordered particle systems.
Source: Physical review. E
DOI: 10.1103/m6bl-dqsd
Authors: Sara Dal Cengio, Romain Mari, Eric Bertin
Language: English
Topic: Micro and Nano Robotics
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: Agence Nationale de la Recherche
OpenAlex ID: W4415166125