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arXiv · 2202.04459

Inducing a bound state between active particles

Pritha Dolai·Simon Krekels·Christian Maes
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Abstract

We show that two active particles can form a bound state by coupling to a driven nonequilibrium environment. We specifically investigate the case of two mutually noninteracting run-and-tumble probes moving on a ring, each in short-range interaction with driven colloids. Under conditions of time-scale separation, these active probes become trapped in bound states. In fact, the bound state appears at high enough persistence (low effective temperature). From the perspective of a co-moving frame, where colloids are in thermal equilibrium and the probes are active and driven, an appealing analogy appears with Cooper pairing, as electrons can be viewed as run-and-tumble particles in a pilot-wave picture.

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Pritha Dolai, Simon Krekels, Christian Maes. 2022-02-09. Inducing a bound state between active particles. https://doi.org/10.1103/physreve.105.044605

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