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arXiv · 1705.00877

Driven Brownian particle as a paradigm for a nonequilibrium heat bath: Effective temperature and cyclic work extraction

Robert Wulfert·Michael Oechsle·Thomas Speck·Udo Seifert
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Abstract

We apply the concept of a frequency-dependent effective temperature based on the fluctuation-dissipation ratio to a driven Brownian particle in a nonequilibrium steady state. Using this system as a thermostat for a weakly coupled harmonic oscillator, the oscillator thermalizes according to a canonical distribution at the respective effective temperature across the entire frequency spectrum. By turning the oscillator from a passive "thermometer" into a heat engine, we realize the cyclic extraction of work from a single thermal reservoir, which is feasible only due to its nonequilibrium nature.

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Robert Wulfert, Michael Oechsle, Thomas Speck, Udo Seifert. 2017-05-02. Driven Brownian particle as a paradigm for a nonequilibrium heat bath: Effective temperature and cyclic work extraction. https://doi.org/10.1103/physreve.95.050103

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