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Quantum Ratchets

Satoshi Yukawa·Macoto Kikuchi·Gen Tatara·Hiroshi Matsukawa
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Abstract

The concept of thermal ratchets is extended to the system governed by quantum mechanics. We study a tight-binding model with an asymmetric periodic potential contacting with a heat bath under an external oscillating field as a specific example of quantum ratchet. Dynamics of a density operator of this system is studied numerically by using the quantum Liouville equation. Finite net current is found in the non-equilibrium steady state. The direction of the current varies with parameters, in contrast with the classical thermal ratchets.

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Satoshi Yukawa, Macoto Kikuchi, Gen Tatara, Hiroshi Matsukawa. 1997-06-25. Quantum Ratchets. https://doi.org/10.1143/jpsj.66.2953

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