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Driven chaotic mesoscopic systems, dissipation and decoherence

Doron Cohen
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Abstract

Driven chaotic systems are of interest in mesoscopic physics, as well as in nuclear, atomic and molecular physics. Such systems [coordinates $(Q,P)$]$ tend to absorb energy. This irreversible effect is known as dissipation. "Driving" means that a parameter $x$ is changed in time. More generally, $x$ may be a dynamical variable. In such case the interaction of $(x,p)$ with the environmental degrees of freedom $(Q,P)$ leads to dephasing as well as to dissipation. We introduce a general framework for the analysis of dissipation and dephasing, and we clarify the tight connection to recent studies of quantum irreversibility (also referred to as "Loschmidt echo" or as the "fidelity" of quantum computation). Specific model systems that will be presented are: particle in a box driven by moving a wall, and particle in a box/ring driven by electro-motive-force. These two examples are related to studies of nuclear friction and mesoscopic conductance.

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Doron Cohen. 2004-03-14. Driven chaotic mesoscopic systems, dissipation and decoherence. https://arxiv.org/abs/quant-ph/0403061

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