TY - JOUR

T1 - Coarsening and clustering in run-and-tumble dynamics with short-range exclusion

AU - Sepúlveda, Néstor

AU - Soto, Rodrigo

N1 - Publisher Copyright:
© 2016 American Physical Society.

PY - 2016/8/9

Y1 - 2016/8/9

N2 - The emergence of clustering and coarsening in crowded ensembles of self-propelled agents is studied using a lattice model in one dimension. The persistent exclusion process, where particles move at directions that change randomly at a low tumble rate α, is extended allowing sites to be occupied by more than one particle, with a maximum nmax per site. Three phases are distinguished. For nmax=1 a gas of clusters form, with sizes distributed exponentially and no coarsening takes place. For nmax≥3 and small values of α, coarsening takes place and few large clusters appear, with a large fraction of the total number of particles in them. In the same range of nmax but for larger values of α, a gas phase where a negligible fraction of particles takes part of clusters. Finally, nmax=2 corresponds to a crossover phase. The character of the transitions between phases is studied extending the model to allow nmax to take real values and jumps to an occupied site are probabilistic. The transition from the gas of clusters to the coarsening phase is continuous and the mass of the large clusters grows continuously when varying the maximum occupancy, and the crossover found corresponds to values close to the transition. The second transition, from the coarsening to the gaseous phase, can be either continuous or discontinuous depending on the parameters, with a critical point separating both cases.

AB - The emergence of clustering and coarsening in crowded ensembles of self-propelled agents is studied using a lattice model in one dimension. The persistent exclusion process, where particles move at directions that change randomly at a low tumble rate α, is extended allowing sites to be occupied by more than one particle, with a maximum nmax per site. Three phases are distinguished. For nmax=1 a gas of clusters form, with sizes distributed exponentially and no coarsening takes place. For nmax≥3 and small values of α, coarsening takes place and few large clusters appear, with a large fraction of the total number of particles in them. In the same range of nmax but for larger values of α, a gas phase where a negligible fraction of particles takes part of clusters. Finally, nmax=2 corresponds to a crossover phase. The character of the transitions between phases is studied extending the model to allow nmax to take real values and jumps to an occupied site are probabilistic. The transition from the gas of clusters to the coarsening phase is continuous and the mass of the large clusters grows continuously when varying the maximum occupancy, and the crossover found corresponds to values close to the transition. The second transition, from the coarsening to the gaseous phase, can be either continuous or discontinuous depending on the parameters, with a critical point separating both cases.

UR - http://www.scopus.com/inward/record.url?scp=84983479554&partnerID=8YFLogxK

U2 - 10.1103/PhysRevE.94.022603

DO - 10.1103/PhysRevE.94.022603

M3 - Article

AN - SCOPUS:84983479554

VL - 94

JO - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics

JF - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics

SN - 1539-3755

IS - 2

M1 - 022603

ER -