Quantum detectors as autonomous machines: assessing the nonequilibrium thermodynamics of information acquisition

TL;DR

This paper models quantum particle detectors as autonomous thermal machines, revealing how entropy production influences measurement efficiency, precision, and noise, and establishing fundamental thermodynamic tradeoffs in quantum detection.

Contribution

It introduces a minimal autonomous quantum detector model linking entropy production to measurement performance, highlighting thermodynamic constraints and tradeoffs.

Findings

Entropy production constrains detection efficiency and precision.

Reducing jitter or dead time increases dark counts.

Thermodynamic costs are fundamental to quantum measurement quality.

Abstract

We formulate a minimal model of a quantum particle detector as an autonomous quantum thermal machine. Our goal is to establish how entropy production, which is needed to maintain the detector out of equilibrium, is linked to the quality of the measurement process. Using our model, we perform a detailed investigation of the detector's key performance characteristics: namely, detection efficiency, gain, jitter, dead time, and dark counts. We find that entropy production constrains both the efficiency and temporal precision of the detection process, in the sense that improved performance generally requires more dissipation. We also find that reducing either the detection jitter or dead time unavoidably increases the rate of dark counts. Our work establishes a quantitative connection between entropy production and the quality of the irreversible detection process, highlights fundamental tradeoffs in the performance of particle detectors, and provides a framework for further investigations of the non-equilibrium thermodynamics of quantum measurement and amplification.