Ancilla measurement-based Quantum Otto engine using double-pair spin architecture

TL;DR

This paper introduces a quantum Otto engine using a dual spin-pair architecture with measurement-based heat exchange, achieving enhanced efficiency and finite power through quantum correlations and ancillary spin control.

Contribution

It proposes a novel measurement-based quantum Otto engine with an ancillary spin pair, surpassing standard efficiency limits via quantum correlations and local control.

Findings

Engine operates with a single heat bath using measurement protocols.

Efficiency exceeds standard quantum Otto limit through local ancillary control.

Quantum correlations enhance engine performance and efficiency modulation.

Abstract

We present a quantum heat engine model utilizing a dual spin-pair architecture, wherein an Otto-like cycle is implemented using a single heat bath. The conventional cold bath is replaced by a measurement protocol, enabling engine operation without the need for a second thermal reservoir. Unlike standard quantum heat engines, our framework employs an ancillary spin pair in a two-dimensional configuration to regulate performance. Operating in finite time, the engine attains finite power, which is enhanced through quantum correlations, specifically correlation between spin pairs and projective measurements on the ancillary pair. The system consists of dual qubit pairs, where one pair serves as the working medium and the other as an ancillary system facilitating measurement-induced heat exchange. We demonstrate that the engine efficiency can exceed the standard quantum Otto limit through local control of the ancillary pair while maintaining nonzero power output. Moreover, correlation between spin pairs enables efficiency modulation via the measurement basis, underscoring the role of quantum resources in optimizing quantum thermal machines.