Impact

Outcomes for industrial and other user communities

The lack of practical primary thermometers constitutes a barrier for the dissemination of the redefined kelvin by the mise-en-pratique for the definition of the kelvin (MeP-K-19) i.e. for addressing industry issues. As a result, the practical primary thermometers developed here are expected to have high impact in industry. This project will provide a technological breakthrough for integrated circuit temperature sensing issues, and also for other related temperature measurement needs e.g. those requiring reliable in-situ long time scale measurements such as space, aircraft, submarine or naval, where sensor retrieval (and hence recalibration) is not feasible. Also, the wide-range primary sensor developed in this project, covering the cryogenic temperature range, is of particular interest for rapidly growing sectors such as Hydrogen (liquid H2 storage) and Quantum Technologies, where temperature-controlled cryostats is crucial. The use of the new sensors developed in this project will enable accurate, zero drift, temperature sensing in the extended operating range (4 K to 500 K) having the capability to be embedded into a chipset or other integrated technologies – a technological breakthrough.

Outcomes for the metrology and scientific communities

The kelvin redefinition has stimulated new and disruptive approaches to delivering temperature traceability, namely practical primary thermometry at the point of measurement. Such approaches better meet user needs by providing lifetime on-demand reliable traceable temperatures. The most innovative ways to provide such traceability are the photonic/quantum-based approaches investigated in this project (in particular, thanks to the high chipset integration capacity and the self-calibration). Whilst in their infancy capacity these approaches have the potential to radically change the practice of thermometry through provision of in situ traceability without the need for sensor removal for recalibration. Beside purely metrological need for a practical primary wide-range thermometer for the realisation and dissemination of the thermodynamic temperature according to the mise-en-pratique for the definition of the kelvin, multiple users would benefit from such an approach: from quantum technologies community to cryogenics, photonic/semiconductor, aerospace, transportation and energy (hydrogen) sectors. The sensors developed in this project are adapted to these applications where usual temperature sensors are unsuitable: self-calibrated optomechanical resonators as well as photonic resonators could provide robust, small-scale and wide-temperature range sensors, immune to electrical noise and easy to integrate.

Outcomes for relevant standards

The practical primary thermometry approach developed will provide a new and more straightforward way to deliver SI traceability direct to where the user needs it most at the point of application. This is a paradigm shift in the way traceability is delivered (currently through an unbroken chain of measurements) and will require validation from the CCT to be accepted and will require some form of a standardisation recommendation before full implementation can be realised. More generally, and within a shorter timeframe, this project will produce technical data and documents for the CCT, via close cooperation with its working groups and task groups. The relevant committees will be kept informed of the progress and outcomes of the project: annual reports to the CCT and RMO TC-Ts. The project consortium will raise awareness of these developments, concerning the quantum sensors and their needs for standardisation, within CEN-CLC Joint Technical Committee 22 Quantum Technologies.

Longer-term economic, social and environmental impacts

Temperature is probably the most frequently and widely used measurement, and it influences almost every physical, chemical, and biological process. Consequently, any change to the fundamentals of thermometry, its measurement and traceability will have far-reaching impacts in all areas of human endeavour. A practical primary thermometer available at the point of use introduces a paradigm change in the traceability scheme to the kelvin: calibration against standards held by a national metrology standard may no longer be required. A simple stable in-situ temperature reference is sufficient to estimate the statistical component of the uncertainty of the primary thermometer. This significantly reduces the complexity of the traceability process as well as its cost. Industry will be more efficient and productive as thermometers will no longer require calibration meaning that optimum energy is used, minimising emissions and waste. The research will have a significant impact at the European level because it enhances the European laboratory network for quantum and nano-scaled temperature metrology (established during EMPIR JRP 17FUN05 PhotOQuanT) and opens new opportunities for the first commercialisation of photonic temperature sensors in Europe. Many industries such as semiconductor, micro- and nanotechnology, aerospace and naval, green energy and quantum technologies, will benefit from the project’s output and this should strengthen European industrial infrastructure for the development of new services and products. The project will improve collaboration between European NMIs, academia and technological institutions enabling the EU to take a leading role in the future in this important emerging technology area.