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arXiv · 2512.24761

Mobility-induced phase separation in a binary mixture of active Brownian particles

D. Jiménez-Flores·A. Rodríguez-Rivas·J. M. Romero-Enrique
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Abstract

In this paper, we report a Brownian dynamics simulation of the mobility-induced phase separation which occurs in a two-dimensional binary mixture of active soft Brownian particles, whose interactions are modeled by non-additive Weeks-Chandler-Andersen potentials inspired in Lennard-Jones potentials used for glass-forming passive mixtures. The analysis of structural properties, such as the radial distribution functions and the hexatic order parameter, shows that the high-density coexisting state in the binary case is spatially disordered, unlike the solid-like state observed for the monocomponent system. Characterization of the mean-square displacement of the active particles shows that both the low- and high-density coexisting states have diffusive behavior for long times. Thus, the high-density coexisting states are liquid-like in the binary cases. Moreover, diffusive behavior is also observed in the high-density solid-like state for the monocomponent system, which is driven by the presence of active topological defects.

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D. Jiménez-Flores, A. Rodríguez-Rivas, J. M. Romero-Enrique. 2025-12-31. Mobility-induced phase separation in a binary mixture of active Brownian particles. https://doi.org/10.1063/5.0304795

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