2026-06-29T15:20:42Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/1349512026-04-23T00:08:34Zcom_20.500.14352_14col_20.500.14352_15

Re-entrant percolation in active Brownian hard disks Evans, David Martín Roca, José Harmer, Nathan J. Valeriani, Chantal Miller, Mark A. 539.1 Equation-of-state Continuum percolation Phase-behavior Particles Aggregation Threshold System Física nuclear 2207 Física Atómica y Nuclear © 2023. The Author(s). UCM predoctoral contract (CT15/23) Non-equilibrium clustering and percolation are investigated in an archetypal model of two-dimensional active matter using dynamic simulations of self-propelled Brownian repulsive particles. We concentrate on the single-phase region up to moderate levels of activity, before motility-induced phase separation (MIPS) sets in. Weak activity promotes cluster formation and lowers the percolation threshold. However, driving the system further out of equilibrium partly reverses this effect, resulting in a minimum in the critical density for the formation of system-spanning clusters and introducing re-entrant percolation as a function of activity in the pre-MIPS regime. This non-monotonic behaviour arises from competition between activity-induced effective attraction (which eventually leads to MIPS) and activity-driven cluster breakup. Using an adapted iterative Boltzmann inversion method, we derive effective potentials to map weakly active cases onto a passive (equilibrium) model with conservative attraction, which can be characterised by Monte Carlo simulations. While the active and passive systems have practically identical radial distribution functions, we find decisive differences in higher-order structural correlations, to which the percolation threshold is highly sensitive. For sufficiently strong activity, no passive pairwise potential can reproduce the radial distribution function of the active system. European Commission Durham University Ministerio de Ciencia, Innovación y Universidades (España) Universidad Complutense de Madrid Depto. de Estructura de la Materia, Física Térmica y Electrónica Fac. de Ciencias Físicas TRUE pub 2026-04-22T08:31:45Z 2026-04-22T08:31:45Z 2024 journal article VoR https://hdl.handle.net/20.500.14352/134951 1744-683X 10.1039/d4sm00975d 1744-6848 eng info:eu-repo/grantAgreement/EC/H2020/730897/EU/Transnational Access Programme for a Pan-European Network of HPC Research Infrastructures and Laboratories for scientific computing/HPC-EUROPA3 info:eu-repo/grantAgreement/UKRI/EPSRC/EP/S023631/1/UK/EPSRC Centre for Doctoral Training in Soft Matter for Formulation and Industrial Innovation (SOFI2)/SOFI2 info:eu-repo/grantAgreement/ISCIII/Plan Estatal de Investigación Científica, Técnica y de Innovación 2021-2023/IHRC22%2F00002/ES/Bacterial biofilm disruption mediated by active colloids/ info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2021-2023/PID2022-140407NB-C21/ES/AUTOORGANIZACION Y DINAMICA EN SISTEMAS DE PARTICULAS ACTIVAS Y ACTUADAS INTERACTUANTES: SIMULACIONES Y EXPERIMENTOS/ Evans, David, et al. «Re-Entrant Percolation in Active Brownian Hard Disks». Soft Matter, vol. 20, n.o 37, 2024, pp. 7484-92. DOI.org (Crossref), https://doi.org/10.1039/D4SM00975D. Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ open access application/pdf