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Anomalous heating in a colloidal system.

ABSTRACT: We report anomalous heating in a colloidal system, an experimental observation of the inverse Mpemba effect, where for two initial temperatures lower than the temperature of the thermal bath, the colder of the two systems heats up faster when coupled to the same thermal bath. For an overdamped, Brownian colloidal particle moving in a tilted double-well potential, we find a nonmonotonic dependence of the heating times on the initial temperature of the system. Entropic effects make the inverse Mpemba effect generically weaker-harder to observe-than the usual Mpemba effect (anomalous cooling). We also observe a strong version of anomalous heating, where a cold system heats up exponentially faster than systems prepared under slightly different conditions.

SUBMITTER: Kumar A

PROVIDER: S-EPMC8812517 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Anomalous heating in a colloidal system.

Kumar Avinash A Chétrite Raphaël R Bechhoefer John J

Proceedings of the National Academy of Sciences of the United States of America 20220201 5

We report anomalous heating in a colloidal system, an experimental observation of the inverse Mpemba effect, where for two initial temperatures lower than the temperature of the thermal bath, the colder of the two systems heats up faster when coupled to the same thermal bath. For an overdamped, Brownian colloidal particle moving in a tilted double-well potential, we find a nonmonotonic dependence of the heating times on the initial temperature of the system. Entropic effects make the inverse Mpe ...[more]

PMID: 35078935

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