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arXiv · 1408.5171

Energy transport between two pure-dephasing reservoirs

T. Werlang·D. Valente
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Abstract

A pure-dephasing reservoir acting on an individual quantum system induces loss of coherence without energy exchange. When acting on composite quantum systems, dephasing reservoirs can lead to a radically different behavior. Transport of energy between two pure-dephasing markovian reservoirs is predicted in this work. They are connected through a chain of coupled sites. The baths are kept in thermal equilibrium at distinct temperatures. Quantum coherence between sites is generated in the steady-state regime and results in the underlying mechanism sustaining the effect. A quantum model for the reservoirs is a necessary condition for the existence of stationary energy transport. A microscopic derivation of the non-unitary system-bath interaction is employed, valid in the ultrastrong inter-site coupling regime. The model assumes that each site-reservoir coupling is local.

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T. Werlang, D. Valente. 2014-08-21. Energy transport between two pure-dephasing reservoirs. https://doi.org/10.1103/physreve.91.012143

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