On quantum interferometric measurements of temperature

TL;DR

This paper introduces a quantum interferometric thermometer capable of nanokelvin precision, outperforming classical pyrometers, with potential applications in ultraprecise temperature measurement and stabilization in quantum optics.

Contribution

It provides a rigorous analysis of quantum interferometric thermometry, demonstrating its superior precision over classical methods and exploring its practical applications.

Findings

Capable of measuring nanokelvin temperatures.

Outperforms idealized classical pyrometers.

Useful for ultraprecise quantum optical experiments.

Abstract

We provide a detailed description of the quantum interferometric thermometer, which is a device that estimates the temperature of a sample from the measurements of the optical phase. For the first time, we rigorously analyze the operation of such a device by studying the interaction of the optical probe system prepared in a single-mode Gaussian state with a heated sample modeled as a dissipative thermal reservoir. We find that this approach to thermometry is capable of measuring the temperature of a sample in the nanokelvin regime. Furthermore, we compare the fundamental precision of quantum interferometric thermometers with the theoretical precision offered by the classical idealized pyrometers, which infer the temperature from a measurement of the total thermal radiation emitted by the sample. We find that the interferometric thermometer provides a superior performance in temperature sensing even when compared with this idealized pyrometer. We predict that interferometric thermometers will prove useful for ultraprecise temperature sensing and stabilization of quantum optical experiments based on the nonlinear crystals and atomic vapors.