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arXiv · 2006.08202

Pair correlation of dilute Active Brownian Particles: from low activity dipolar correction to high activity algebraic depletion wings

Alexis Poncet·Olivier Bénichou·Vincent Démery·Daiki Nishiguchi
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Abstract

We study the pair correlation of Active Brownian Particles at low density using numerical simulations and analytical calculations. We observe a winged pair correlation: while particles accumulate in front of an active particle as expected, the depletion wake consists of two depletion wings. In the limit of soft particles, we obtain a closed equation for the pair correlation, allowing us to characterize the depletion wings. In particular, we unveil two regimes at high activity where the wings adopt a self-similar profile and decay algebraically. We also perform experiments of self-propelled Janus particles and indeed observe the depletion wings.

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BibTeXRIS

Alexis Poncet, Olivier Bénichou, Vincent Démery, Daiki Nishiguchi. 2020-06-15. Pair correlation of dilute Active Brownian Particles: from low activity dipolar correction to high activity algebraic depletion wings. https://doi.org/10.1103/physreve.103.012605

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