Standard photonic (quantum) thermometry in the UK

Two emerging developments in photon based (quantum) thermometry are described, namely, active ring-resonator thermometry (ARRT) and small-scale practical Doppler broadening thermometry (pDBT). These developments are sensing methodologies that are frequency based and directly linked to the physics of the measurement approach. Through relying on the physics instead of external calibration to provide reliable thermometry direct traceability to the kelvin is obtained. The medium-term objective of this work is to develop practical primary thermometers that need no external calibration, having modest uncertainties (0.1–1 K) but able to provide reliable thermodynamic temperatures, during the lifetime of the required measurements. The long-term objective is to develop these (and possibly other) photon-based practical primary temperature measurement methods that can be widely deployed, supplanting conventional techniques but providing reliable permanent traceability to the kelvin in the measurement setting.