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arXiv · 2501.00918

Achievable Information-Energy Exchange in a Brownian Information Engine through Potential Profiling

Rafna Rafeek·Debasish Mondal
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Abstract

The information engine extracts work from a single heat bath using mutual information obtained during the operation cycle. This study investigates the influence of the potential shaping in a Brownian information engine (BIE) in harnessing the information from thermal fluctuations. We have designed a BIE by considering an overdamped Brownian particle inside a confined potential and introducing an appropriate symmetric feedback cycle. We find that the upper bound of the extractable work for a BIE with a monostable centrosymmetric confining potential, with a stable state at the potential centre, depends on the bath temperature and the convexity of the confinement. A concave confinement is more efficient for an information-energy exchange. For a bistable confinement with an unstable centre and two symmetric stable basins, one can find an engine-to-refrigeration transition beyond a certain barrier height related to the energy difference between the energy barrier and the stable basins. Finally, we use the concavity-induced gain in information harnessing to device a BIE in the presence of a multistable potential that can harvest even more energy than monostable confinement.

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Rafna Rafeek, Debasish Mondal. 2025-01-01. Achievable Information-Energy Exchange in a Brownian Information Engine through Potential Profiling. https://doi.org/10.1021/acs.jpcb.5c00036

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