Markovian heat engine boosted by quantum coherence

TL;DR

This paper demonstrates that quantum coherence can enhance the efficiency of a Markovian quantum heat engine beyond classical limits by utilizing a quantum Otto cycle, with experimental simulation and thermodynamic cost analysis.

Contribution

It introduces a method to boost heat engine efficiency using quantum coherence and provides a detailed simulation of the cycle with noise and thermodynamic cost measurement.

Findings

Quantum coherence can surpass classical efficiency limits.

Amplitude damping increases work extraction and efficiency.

Phase damping increases work but reduces efficiency.

Abstract

We evaluate the role of quantum coherence as a thermodynamic resource in a noisy, Markovian, one-qubit heat engine. By consuming the coherence of noisy quantum states, we demonstrate that the engine can surpass the classical efficiency limit when operating according to a quantum Otto cycle. The engine's non-classical nature is demonstrated by its violation of the Leggett-Garg's temporal correlations inequality. Amplitude damping increases the extractable work under partial thermalization, thereby increasing the efficiency. In contrast, phase damping increases the extractable work under partial thermalization but reduces the efficiency. We implement the entire Otto cycle in a quantum circuit, simulating realistic amplitude and phase damping channels, as well as gate-level noise. We introduce an operational measure of the circuit's thermodynamic cost to establish a direct link between energy consumption and information processing in quantum heat engines.