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Quantum Ratchets at High Temperatures

D. Zueco·J. L. Garcia-Palacios
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Abstract

Using the continued-fraction method we solve the Caldeira-Leggett master equation in the phase-space (Wigner) representation to study Quantum ratchets. Broken spatial symmetry, irreversibility and periodic forcing allows for a net current in these systems. We calculate this current as a function of the force under adiabatic conditions. Starting from the classical limit we make the system quantal. In the quantum regime tunnel events and over-barrier wave reflection phenomena modify the classical result. Finally, using the phase-space formalism we give some insights about the decoherence in these systems.

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D. Zueco, J. L. Garcia-Palacios. 2004-12-21. Quantum Ratchets at High Temperatures. https://doi.org/10.1016/j.physe.2005.05.043

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