Focusing by blocking: repeatedly generating central density peaks in self-propelled particle systems by exploiting diffusive processes

Andreas M. Menzel

doi:10.1209/0295-5075/110/38005

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arXiv · 1505.01706

Focusing by blocking: repeatedly generating central density peaks in self-propelled particle systems by exploiting diffusive processes

Andreas M. Menzel

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Abstract

Over the past few years the displacement statistics of self-propelled particles has been intensely studied, revealing their long-time diffusive behavior. Here, we demonstrate that a concerted combination of boundary conditions and switching on and off the self-propelling drive can generate and afterwards arbitrarily often restore a non-stationary centered peak in their spatial distribution. This corresponds to a partial reversibility of their statistical behavior, in opposition to the above-mentioned long-time diffusive nature. Interestingly, it is a diffusive process that mediates and makes possible this procedure. It should be straightforward to verify our predictions in a real experimental system.

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Andreas M. Menzel. 2015-05-07. Focusing by blocking: repeatedly generating central density peaks in self-propelled particle systems by exploiting diffusive processes. https://doi.org/10.1209/0295-5075/110/38005

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