Bridging thermodynamics and metrology in non-equilibrium Quantum Thermometry

TL;DR

This paper explores how quantum coherence affects non-equilibrium quantum thermometry, linking thermodynamics and metrology, supported by experimental photonic simulations.

Contribution

It introduces a generalized relation between temperature uncertainty and quantum effects in non-equilibrium conditions, advancing quantum thermometry.

Findings

Quantum coherence enhances temperature measurement precision.

Experimental photonic simulation confirms theoretical predictions.

Non-equilibrium regimes offer improved thermometric accuracy.

Abstract

Single-qubit thermometry presents the simplest tool to measure the temperature of thermal baths with reduced invasivity. At thermal equilibrium, the temperature uncertainty is linked to the heat capacity of the qubit, however the best precision is achieved outside equilibrium condition. Here, we discuss a way to generalize this relation in a non-equilibrium regime, taking into account purely quantum effects such as coherence. We support our findings with an experimental photonic simulation.