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arXiv · 2111.06109

Anomalous cooling and overcooling of active systems

Fabian Jan Schwarzendahl·Hartmut Löwen
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Abstract

The phenomenon that a system at a hot temperature cools faster than at a warm temperature, referred to as the Mpemba effect, has been recently realized for trapped colloids. Here, we investigate the cooling and heating process of a self-propelling active colloid using numerical simulations and theoretical calculations with a model that can directly be tested in experiments. Upon cooling the particles' active motion induces a Mpemba effect. Transiently the system can even exhibit smaller temperatures than its final temperature, a surprising phenomenon which we refer to as activity-induced overcooling.

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Fabian Jan Schwarzendahl, Hartmut Löwen. 2021-11-11. Anomalous cooling and overcooling of active systems. https://doi.org/10.1103/physrevlett.129.138002

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