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arXiv · 1803.06159

Generalized thermodynamics of Motility-Induced Phase Separation: Phase equilibria, Laplace pressure, and change of ensembles

Alexandre P. Solon·Joakim Stenhammar·Michael E. Cates·Yariv Kafri·Julien Tailleur
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Abstract

Motility-induced phase separation (MIPS) leads to cohesive active matter in the absence of cohesive forces. We present, extend and illustrate a recent generalized thermodynamic formalism which accounts for its binodal curve. Using this formalism, we identify both a generalized surface tension, that controls finite-size corrections to coexisting densities, and generalized forces, that can be used to construct new thermodynamic ensembles. Our framework is based on a nonequilibrium generalization of the Cahn-Hilliard equation and we discuss its application to active particles interacting either via quorum-sensing interactions or directly through pairwise forces.

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Alexandre P. Solon, Joakim Stenhammar, Michael E. Cates, Yariv Kafri, Julien Tailleur. 2018-10-10. Generalized thermodynamics of Motility-Induced Phase Separation: Phase equilibria, Laplace pressure, and change of ensembles. https://doi.org/10.1088/1367-2630%2Faaccdd

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