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arXiv · 0708.0192

Motion by Stopping: Rectifying Brownian Motion of Non-spherical Particles

Susan Sporer·Christian Goll·Klaus Mecke
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Abstract

We show that Brownian motion is spatially not symmetric for mesoscopic particles embedded in a fluid if the particle is not in thermal equilibrium and its shape is not spherical. In view of applications on molecular motors in biological cells, we sustain non-equilibrium by stopping a non-spherical particle at periodic sites along a filament. Molecular dynamics simulations in a Lennard-Jones fluid demonstrate that directed motion is possible without a ratchet potential or temperature gradients if the asymmetric non-equilibrium relaxation process is hindered by external stopping. Analytic calculations in the ideal gas limit show that motion even against a fluid drift is possible and that the direction of motion can be controlled by the shape of the particle, which is completely characterized by tensorial Minkowski functionals.

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Susan Sporer, Christian Goll, Klaus Mecke. 2007-08-01. Motion by Stopping: Rectifying Brownian Motion of Non-spherical Particles. https://doi.org/10.1103/physreve.78.011917

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