Quantum precision thermometry with weak measurements

Abstract

As the minituarization of electronic devices, which are sensitive to temperature, grows apace, sensing of temperature with ever smaller probes is more important than ever. Genuinely quantum mechanical schemes of thermometry are thus expected to be crucial to future technological progress. We propose an alternative method to measure the temperature of a bath using the weak measurement scheme with a finite-dimensional probe. The precision offered by the present scheme not only shows similar qualitative features as the usual quantum-Fisher-information-based thermometric protocols, but also allows for flexibility over setting the optimal thermometric window through the judicious choice of postselection measurements.