Collective performance of a finite-time quantum Otto cycle
Abstract
We study the finite-time effects in a quantum Otto cycle where a collective spin system is used as the working fluid. Starting from a simple one-qubit system we analyze the transition to the limit cycle in the case of a finite-time thermalization. If the system consists of a large sample of independent qubits interacting coherently with the heat bath, the superradiant equilibration is observed. We show that this phenomenon can boost the power of the engine. Mutual interaction of qubits in the working fluid is modeled by the Lipkin-Meshkov-Glick Hamiltonian. We demonstrate that in this case the quantum phase transitions for the ground and excited states may have a strong negative effect on the performance of the machine. Reversely, by analyzing the work output we can distinguish between the operational regimes with and without a phase transition.
Keywords
Cite
@article{arxiv.1905.08692,
title = {Collective performance of a finite-time quantum Otto cycle},
author = {Michal Kloc and Pavel Cejnar and Gernot Schaller},
journal= {arXiv preprint arXiv:1905.08692},
year = {2019}
}
Comments
13 pages, 11 figures