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arXiv · 2011.02528

Self-motility of an active particle induced by correlations in the surrounding solution

Alvaro Domínguez·M. N. Popescu·C. M. Rohwer·S. Dietrich
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Abstract

Current models of phoretic transport rely on molecular forces creating a "diffuse" particle-fluid interface. We investigate theoretically an alternative mechanism, in which a diffuse interface emerges solely due to a non-vanishing correlation length of the surrounding solution. This mechanism can drive self-motility of a chemically active particle. Numerical estimates indicate that the velocity can reach micrometers per second. The predicted phenomenology includes a bilinear dependence of the velocity on the activity and a possible double velocity reversal upon varying the correlation length.

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Alvaro Domínguez, M. N. Popescu, C. M. Rohwer, S. Dietrich. 2020-11-04. Self-motility of an active particle induced by correlations in the surrounding solution. https://doi.org/10.1103/physrevlett.125.268002

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