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arXiv · 2206.14751

Strongly coupled quantum Otto cycle with single qubit bath

Sagnik Chakraborty·Arpan Das·Dariusz Chruściński
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Abstract

We discuss a model of a closed quantum evolution of two-qubits where the joint Hamiltonian is so chosen that one of the qubits acts as a bath and thermalize the other qubit which is acting as the system. The corresponding exact master equation for the system is derived. Interestingly, for a specific choice of parameters the master equation takes the Gorini-Kossakowski-Lindblad-Sudarshan (GKLS) form with constant coefficients, representing pumping and damping of a single qubit system. Based on this model we construct an Otto cycle connected to a single qubit bath and study its thermodynamic properties. Our analysis goes beyond the conventional weak coupling scenario and illustrates the effects of finite bath including non-Markovianity. We find closed form expressions for efficiency (coefficient of performance), power (cooling power) for heat engine regime (refrigerator regime) for different modifications of the joint Hamiltonian.

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Sagnik Chakraborty, Arpan Das, Dariusz Chruściński. 2022-06-29. Strongly coupled quantum Otto cycle with single qubit bath. https://doi.org/10.1103/physreve.106.064133

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