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

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.

6 pages, 2 figures, and 22 pages of supplemental material. To be published as Phys. Rev. Lett

References in corpus (4)

• Propulsion of a molecular machine by asymmetric distribution of reaction--products
• Designing phoretic micro- and nano-swimmers
• Tuning the motility and directionality of self-propelled colloids
• Floor- or ceiling-sliding for chemically active, gyrotactic, sedimenting Janus particles

Cited by in corpus (6)

• Active spheres induce Marangoni flows that drive collective dynamics
• Spontaneous propulsion of an isotropic colloid in a phase-separating environment
• Conditions for the propulsion of a colloid surrounded by a mesoscale phase separation
• Ionic self-phoresis maps onto correlation-induced self-phoresis
• Force-dependence of the rigid-body motion for an arbitrarily shaped particle in a forced, incompressible Stokes flow
• Self-chemophoresis in the thin diffuse interface approximation