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arXiv · 2010.02853

Magnetic microswimmers exhibit Bose-Einstein-like condensation

Abstract

We study an active matter system comprised of magnetic microswimmers confined in a microfluidic channel and show that it exhibits a new type of self-organized behavior. Combining analytical techniques and Brownian dynamics simulations, we demonstrate how the interplay of non-equilibrium activity, external driving, and magnetic interactions leads to the condensation of swimmers at the center of the channel via a non-equilibrium phase transition that is formally akin to Bose-Einstein condensation. We find that the effective dynamics of the microswimmers can be mapped onto a diffusivity-edge problem, and use the mapping to build a generalized thermodynamic framework, which is verified by a parameter-free comparison with our simulations. Our work reveals how driven active matter has the potential to generate exotic classical non-equilibrium phases of matter with traits that are analogous to those observed in quantum systems.

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Fanlong Meng, Daiki Matsunaga, Benoît Mahault, Ramin Golestanian. 2020-10-06. Magnetic microswimmers exhibit Bose-Einstein-like condensation. https://doi.org/10.1103/physrevlett.126.078001

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