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Separation quality of a geometric ratchet

C. Keller·Florian Marquardt·C. Bruder
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Abstract

We consider an experimentally relevant model of a geometric ratchet in which particles undergo drift and diffusive motion in a two-dimensional periodic array of obstacles, and which is used for the continuous separation of particles subject to different forces. The macroscopic drift velocity and diffusion tensor are calculated by a Monte-Carlo simulation and by a master-equation approach, using the correponding microscopic quantities and the shape of the obstacles as input. We define a measure of separation quality and investigate its dependence on the applied force and the shape of the obstacles.

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C. Keller, Florian Marquardt, C. Bruder. 2001-12-14. Separation quality of a geometric ratchet. https://doi.org/10.1103/physreve.65.041927

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