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Demon-free quantum Brownian motors

L. Machura·M. Kostur·P. Hänggi·P. Talkner·J. L uczka
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Abstract

A quantum Smoluchowski equation is put forward that consistently describes thermal quantum states. In particular, it notably does not induce a violation of the second law of thermodynamics. This so modified kinetic equation is applied to study {\it analytically} directed quantum transport at strong friction in arbitrarily shaped ratchet potentials that are driven by nonthermal two-state noise. Depending on the mutual interplay of quantum tunneling and quantum reflection these quantum corrections can induce both, either a sizable enhancement or a suppression of transport. Moreover, the threshold for current reversals becomes markedly shifted due to such quantum fluctuations.

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L. Machura, M. Kostur, P. Hänggi, P. Talkner, J. L uczka. 2004-02-04. Demon-free quantum Brownian motors. https://doi.org/10.1103/physreve.70.031107

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