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arXiv · 2403.18329

Bulk condensation by an active interface

Raushan Kant·Rahul Kumar Gupta·Harsh Soni·A K Sood·Sriram Ramaswamy
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Abstract

We present experiments, supported by mechanically detailed simulations, establishing bulk vapor-liquid condensation of a hard-bead fluid by a tiny population of orientable motile grains that self-assembles into a moving polarized monolayer. In a quasi-1D geometry two such layers, oppositely aligned, immobilize the condensed non-motile component. We account for our observations through a continuum theory with a naturally non-reciprocal Cahn-Hilliard structure, whose predicted trends as a function of packing fraction are consistent with our observations.

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Raushan Kant, Rahul Kumar Gupta, Harsh Soni, A K Sood, Sriram Ramaswamy. 2024-03-27. Bulk condensation by an active interface. https://doi.org/10.1103/physrevlett.133.208301

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