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arXiv · 2111.00296

Correlation-Enabled Energy Exchange in Quantum Systems without External Driving

T. Pyhäranta·S. Alipour·A. T. Rezakhani·T. Ala-Nissila
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Abstract

We study the role of correlation in mechanisms of energy exchange between an interacting bipartite quantum system and its environment by decomposing the energy of the system to local and correlation-related contributions. When the system Hamiltonian is time-independent, no external work is performed. In this case, energy exchange between the system and its environment occurs only due to the change in the state of the system. We investigate possibility of a special case where the energy exchange with the environment occurs exclusively due to changes in the correlation between the constituent parts of the bipartite system, while their local energies remain constant. We find sufficient conditions for preserving local energies. It is proven that under these conditions and within the Gorini-Kossakowski-Lindblad-Sudarshan (GKLS) dynamics this scenario is not possible for all initial states of the bipartite system. Nevertheless, it is still possible to find special initial states for which the local energies remain unchanged during the associated evolution and the whole energy exchange is only due to the change in the correlation energy. We illustrate our results with an example.

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T. Pyhäranta, S. Alipour, A. T. Rezakhani, T. Ala-Nissila. 2021-10-30. Correlation-Enabled Energy Exchange in Quantum Systems without External Driving. https://doi.org/10.1103/physreva.105.022204

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