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arXiv · 2109.12648

Geometric optimization of non-equilibrium adiabatic thermal machines and implementation in a qubit system

Pablo Terren Alonso·Paolo Abiuso·Marti Perarnau-Llobet·Liliana Arrachea
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Abstract

We adopt a geometric approach to describe the performance of adiabatic quantum machines, operating under slow time-dependent driving and in contact to two or more reservoirs with a temperature bias during all the cycle. We show that the problem of optimizing the power generation of a heat engine and the efficiency of both the heat engine and refrigerator operational modes is reduced to an isoperimetric problem with non-trivial underlying metrics and curvature. This corresponds to the maximization of the ratio between the area enclosed by a closed curve and its corresponding length. We illustrate this procedure in a qubit coupled to two reservoirs operating as a thermal machine by means of an adiabatic protocol.

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Pablo Terren Alonso, Paolo Abiuso, Marti Perarnau-Llobet, Liliana Arrachea. 2021-09-26. Geometric optimization of non-equilibrium adiabatic thermal machines and implementation in a qubit system. https://doi.org/10.1103/prxquantum.3.010326

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