arXiv:2105.14358 · Physical Review A

Enhancing energy transfer in quantum systems via periodic driving: Floquet master equations

Z. Nafari Qaleh, A. T. Rezakhani

Published Jan 12, 2022• 11 citations

Abstract

We provide a comprehensive study of the energy-transfer phenomenon---populating a given energy level---in three- and four-level quantum systems coupled to two thermal baths. In particular, we examine the effects of an external periodic driving and the coherence induced by the baths on the efficiency of the energy transfer. We consider the Floquet-Lindblad and the Floquet-Redfield scenarios, which both are in the Born-Markov, weak-coupling regime but differ in the treatment of the secular approximation, and for the latter we develop an appropriate Floquet-type master equation by employing a partial secular approximation. Throughout the whole analysis we keep Lamb-shift corrections in the master equations. We observe that, especially in the Floquet-Redfield scenario, the driving field can enhance the energy-transfer efficiency compared to the nondriven scenario. In addition, unlike nondriven degenerate systems where Lamb-shift corrections do not contribute significantly to the energy transfer, in the Redfield and the Floquet-Redfield scenarios these corrections have non-negligible effects.

DOI: 10.1103/physreva.105.012208

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