Dynamically Emergent Quantum Thermodynamics: Non-Markovian Otto Cycle

TL;DR

This paper explores how non-Markovian effects and strong system-bath couplings influence the quantum Otto cycle, revealing conditions under which memory effects enhance work output and efficiency.

Contribution

It introduces an exact treatment of non-Markovian dynamics in quantum thermodynamics using a quantum master equation and analyzes their impact on the Otto cycle performance.

Findings

Non-Markovian baths can induce work transfer to the system.

Enhanced work output and efficiency occur near spectral density peaks.

Memory effects are significant in specific parameter regimes.

Abstract

Employing a recently developed approach to dynamically emergent quantum thermodynamics, we revisit the thermodynamic behavior of the quantum Otto cycle with a focus on memory effects and strong system-bath couplings. Our investigation is based on an exact treatment of non-Markovianity by means of an exact quantum master equation, modelling the dynamics through the Fano-Anderson model featuring a peaked environmental spectral density. By comparing the results to the standard Markovian case, we find that non-Markovian baths can induce work transfer to the system, and identify specific parameter regions which lead to enhanced work output and efficiency of the cycle. In particular, we demonstrate that these improvements arise when the cycle operates in a frequency interval which contains the peak of the spectral density. This can be understood from an analysis of the renormalized frequencies emerging through the system-baths couplings.