Universal Characterization of Quantum Vacuum Measurement Engines

TL;DR

This paper introduces a universal theoretical framework for quantum vacuum measurement engines using the quantum vacuum bending function (QVBF), which characterizes energy lowering and governs thermodynamic properties regardless of microscopic details.

Contribution

The paper develops a general theory of quantum vacuum measurement engines based on the QVBF, unifying thermodynamic observables and fluctuations through the ground-state energy landscape.

Findings

QVBF determines work and efficiency in quantum engines

Work fluctuations are linked to QVBF curvature and quantum Fisher information

Theory confirmed by solvable models and numerical simulations

Abstract

Quantum measurements can inject energy into quantum systems, enabling engines whose operation is powered entirely by measurements. We develop a general theory of quantum vacuum measurement engines by introducing the quantum vacuum bending function (QVBF), a quantity that characterizes the lowering of the ground-state energy due to interactions. We show that all thermodynamic observables, including work and efficiency, are governed solely by the shape of the ground-state energy landscape encoded in the QVBF, regardless of microscopic details. We further demonstrate that work fluctuations are defined by the curvature of QVBF modulated by a model-dependent quantity, and are constrained by a generalized quantum fluctuation relation that involves the interplay between quantum Fisher information and the ground-state energy landscape. Exactly solvable models and numerical simulations of single and many-body systems confirm the theory and illustrate how the QVBF alone determines the performance of quantum vacuum measurement engines.