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arXiv · 1710.06306

Maxwell's demon in the quantum-Zeno regime and beyond

G. Engelhardt·G. Schaller
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Abstract

The long-standing paradigm of Maxwell's demon is till nowadays a frequently investigated issue, which still provides interesting insights into basic physical questions. Considering a single-electron transistor, where we implement a Maxwell demon by a piecewise-constant feedback protocol, we investigate quantum implications of the Maxwell demon. To this end, we harness a dynamical coarse-graining method, which provides a convenient and accurate description of the system dynamics even for high measurement rates. In doing so, we are able to investigate the Maxwell demon in a quantum-Zeno regime leading to transport blockade. We argue that there is a measurement rate providing an optimal performance. Moreover, we find that besides building up a chemical gradient, there can be also a regime where additionally the system under consideration provides energy to the demon due to the quantum measurement.

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G. Engelhardt, G. Schaller. 2017-10-17. Maxwell's demon in the quantum-Zeno regime and beyond. https://doi.org/10.1088/1367-2630/aaa38d

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