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arXiv · 1409.3929

Generalized energy equipartition in harmonic oscillators driven by active baths

Claudio Maggi·Matteo Paoluzzi·Nicola Pellicciotta·Alessia Lepore·Luca Angelani·Roberto Di Leonardo
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Abstract

We study experimentally and numerically the dynamics of colloidal beads confined by a harmonic potential in a bath of swimming E. coli bacteria. The resulting dynamics is well approximated by a Langevin equation for an overdamped oscillator driven by the combination of a white thermal noise and an exponentially correlated active noise. This scenario leads to a simple generalization of the equipartition theorem resulting in the coexistence of two different effective temperatures that govern dynamics along the flat and the curved directions in the potential landscape.

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Claudio Maggi, Matteo Paoluzzi, Nicola Pellicciotta, Alessia Lepore, Luca Angelani, Roberto Di Leonardo. 2015-06-26. Generalized energy equipartition in harmonic oscillators driven by active baths. https://doi.org/10.1103/physrevlett.113.238303

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