Large-Range Quantum Optomechanical Thermometry – LaRaQrOfT

Quantum Optomechanics is a disruptive technology which is experiencing an unstoppable progress that could help face up to present metrology challenges. A particularly exciting new development is the possibility of nano-optomechanical systems to produce quantum primary standards that use fundamental aspects of quantum mechanics to gauge thermodynamical quantities.
The aim of LaRaQrOfT is to demonstrate and validate innovative primary temperature sensors using quantum technologies that could either work at low temperature near the quantum regime of the device up to room temperature far from this regime. The monitoring of both thermal and quantum fluctuations of a mechanical resonator allow to scale the size level of thermal motion in term of quantum energies determined by Planck’s constant and can lead to a quantum primary determination of the temperature. Moreover optomechanical devices provide a small, reliable and cost effective primary temperature sensing method that could be used with exchange gazes or liquid without compromising the measurement. All this aspect addresses both a metrological and an industrial challenge, with a self-calibrated, integrated and easily thermalizable sensor.
The project LaRaQrOfT brings together French leading players in the field of optomechanics, nanofabrication and temperature metrology. The Optomechanics and Quantum Measurements team of LKB is a pioneering group in the domain of cavity optomechanics and has widely studied thermal effects and quantum correlations in optomechanical devices necessary to the success of the project. Micro-fabrication will be supported by the state of the art clean-room facilities housed by C2N which has a thorough knowledge of the fabrication of photonics and phononics crystals. Finally CNAM and LNE with their unique expertise in temperature metrology, will develop methods for the metrological validation of the optomechanical thermometer, and its traceability to the International Temperature Scale.