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arXiv · 2512.18615

Phase separation kinetics of 2-TIPS at low density: Cluster growth by ballistic agglomeration

Nayana Venkatareddy·Partha Sarathi Mondal·Shradha Mishra·Prabal K. Maiti
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Abstract

We study the kinetics of two-temperature induced phase separation (2-TIPS) in dilute binary mixtures of active ("hot") and passive ("cold") particles using molecular dynamics simulations and a coarse-grained hydrodynamic model. Following a temperature quench, cold particles nucleate into mobile clusters that move ballistically and merge through successive coalescence events. The resulting domain growth exhibits dynamic scaling with a growth exponent of approximately 0.7, markedly faster than diffusive coarsening. We identify this regime as ballistic agglomeration of cold clusters, demonstrating a distinct nonequilibrium growth mechanism in low-density scalar active systems.

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Nayana Venkatareddy, Partha Sarathi Mondal, Shradha Mishra, Prabal K. Maiti. 2025-12-21. Phase separation kinetics of 2-TIPS at low density: Cluster growth by ballistic agglomeration. https://arxiv.org/abs/2512.18615

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