Photonic and Optomechanical Thermometry

Temperature is one of the most relevant physical quantities that affects almost all processes in nature. However, the realization of accurate temperature standards using current temperature references, like the triple point of water, is difficult due to the requirements on material purity and stability of the environment. In addition, in harsh environments, current temperature sensors with electrical readout, like platinum resistors, are difficult to implement, urging the development of optical temperature sensors. In 2018, the European consortium Photoquant, consisting of metrological institutes and academic partners, started investigating new temperature standards for self-calibrated, embedded optomechanical sensor applications, as well as optimised high resolution and high re- liability photonic sensors, to measure temperature at the nano and meso-scales and as a possible replacement for the standard platinum resistant thermometers. This article presents an overview of the results obtained with sensor prototypes that exploit photonic and optomechanical techniques for sensing temperatures over a large temperature range (5 K to 300 K). Different concepts are demon- strated, including ring resonators, ladder-like resonators and suspended membrane optomechanical thermometers, highlighting initial performance and challenges, like self-heating that need to be overcome to realize photonic and optomechanical thermometry applications.This work was carried out under the 17FUN05 PhotOQuanT project, which has received funding from the EMPIR program, co-financed by the Participating States and the European Union’s Horizon 2020 research and innovation progra

Le kelvin quantique : mesure optomécanique de température par corrélations quantiques et validation métrologique

In 2019, the International Committee for Weights and Measures redefined the various units of the International System of Units by setting the values of the fundamental constants associated with them. Kelvin has been redefined by setting Planck's constant and Boltzmann's constant. This redefinition spurred the development of new primary temperature sensors to disseminate the new Kelvin. Sensors based on quantum technologies are very popular in the metrology community.In this context, we propose a multimodal temperature sensor whose operation is based on the optical and optomechanical properties of a 1D photonic crystal. Indeed, under the effect of temperature, the resonator sees its optical resonance frequency shift, and the Brownian motion induced by the surrounding thermal bath changes. These two effects allow the temperature of the resonator to be determined in two different ways, provided that the calibration is correct. This type of optomechanical resonator opens the way to self-calibrating primary temperature sensors with quantum correlations resulting from the radiation pressure force exerted by light.En 2019, le comité international des poids et mesures a redéfini les différentes unités du système international en particulier le kelvin qui se base désormais sur les constantes de Planck et de Boltzmann dont les valeurs ont été fixées. Cette redéfinition a suscité le développement de nouveaux capteurs de température primaire permettant la dissémination du nouveau Kelvin. Les capteurs se basant sur les technologies quantiques sont très plébiscités par la communauté de métrologie.Dans ce contexte, nous proposons un capteur de température multimodal dont le fonctionnement repose sur les propriétés optique et optomécanique d'un cristal optomécanique à cristaux photoniques 1D. Sous l'effet de la température le résonateur voit sa fréquence de résonance optique se décaler et le mouvement Brownien induit par le bain thermique environnant varier. Ces deux effets permettent de remonter à la température du résonateur de deux manières différentes, à condition de pouvoir calibrer la chaîne de mesure. Ce type de résonateurs optomécaniques ouvre la voie vers des capteurs de température primaires auto-calibrés avec des corrélations quantiques résultantes de la force de pression de radiation exercée par la lumière

Le kelvin quantique : mesure optomécanique de température par corrélations quantiques et validation métrologique

En 2019, le comité international des poids et mesures a redéfini les différentes unités du système international en particulier le kelvin qui se base désormais sur les constantes de Planck et de Boltzmann dont les valeurs ont été fixées. Cette redéfinition a suscité le développement de nouveaux capteurs de température primaire permettant la dissémination du nouveau Kelvin. Les capteurs se basant sur les technologies quantiques sont très plébiscités par la communauté de métrologie.Dans ce contexte, nous proposons un capteur de température multimodal dont le fonctionnement repose sur les propriétés optique et optomécanique d'un cristal optomécanique à cristaux photoniques 1D. Sous l'effet de la température le résonateur voit sa fréquence de résonance optique se décaler et le mouvement Brownien induit par le bain thermique environnant varier. Ces deux effets permettent de remonter à la température du résonateur de deux manières différentes, à condition de pouvoir calibrer la chaîne de mesure. Ce type de résonateurs optomécaniques ouvre la voie vers des capteurs de température primaires auto-calibrés avec des corrélations quantiques résultantes de la force de pression de radiation exercée par la lumière.In 2019, the International Committee for Weights and Measures redefined the various units of the International System of Units by setting the values of the fundamental constants associated with them. Kelvin has been redefined by setting Planck's constant and Boltzmann's constant. This redefinition spurred the development of new primary temperature sensors to disseminate the new Kelvin. Sensors based on quantum technologies are very popular in the metrology community.In this context, we propose a multimodal temperature sensor whose operation is based on the optical and optomechanical properties of a 1D photonic crystal. Indeed, under the effect of temperature, the resonator sees its optical resonance frequency shift, and the Brownian motion induced by the surrounding thermal bath changes. These two effects allow the temperature of the resonator to be determined in two different ways, provided that the calibration is correct. This type of optomechanical resonator opens the way to self-calibrating primary temperature sensors with quantum correlations resulting from the radiation pressure force exerted by light

Photonic and Optomechanical Thermometry

International audienceTemperature is one of the most relevant physical quantities that affects almost all processes in nature. However, the realization of accurate temperature standards using current temperature references, like the triple point of water, is difficult due to the requirements on material purity and stability of the environment. In addition, in harsh environments, current temperature sensors with electrical readout, like platinum resistors, are difficult to implement, urging the development of optical temperature sensors. In 2018, the European consortium Photoquant, consisting of metrological institutes and academic partners, started investigating new temperature standards for self-calibrated, embedded optomechanical sensor applications, as well as optimised high resolution and high reliability photonic sensors, to measure temperature at the nano and meso-scales and as a possible replacement for the standard platinum resistant thermometers. This article presents an overview of the results obtained with sensor prototypes that exploit photonic and optomechanical techniques for sensing temperatures over a large temperature range (5 K to 300 K). Different concepts are demonstrated, including ring resonators, ladder-like resonators and suspended membrane optomechanical thermometers, highlighting initial performance and challenges, like self-heating that need to be overcome to realize photonic and optomechanical thermometry applications