Enhancing the work extraction of the entanglement engine via quantum coherence

Abstract

Studying the relationship between quantum coherence and energy is an intriguing and vital subject in quantum thermodynamics. Quantum engine provides an excellent platform to emphasize it. By constructing a bipartite entanglement engine (BEE) model consisting of a single qubit as the target qubit and a two-qubit as the ancilla, we have investigated the influence of quantum coherence of ancilla on work extraction of BEE at length, and analytically calculated the extractable work of BEE for the ancilla with quantum coherence (QC). We found that the extractable work of BEE is not only dependent on coherence magnitude but also related to the coherence phase of ancilla. Moreover, under certain coherent parameters, the QC can boost the work extraction from BEE. The study reveals the role of QC acting as “fuel” of engine well which deepens the understanding of the energetic effect of QC.