Abstract
With the redefinition of the kelvin in 2019 and the new mise en pratique for the definition of the kelvin (MeP-K) [1], the realization of the kelvin is no longer exclusively confined to the International Temperature Scales (ITS-90, PLTS-2000). Primary thermometry has become possible as an alternative method for the realization of the kelvin. For that purpose, different primary thermometers, specifically the primary magnetic field fluctuation thermometer (pMFFT), the Coulomb blockade thermometer (CBT) and the acoustic gas thermometer (AGT) have been optimized in the EMPIR project Real-K [2] for an extended operation range to cover, at least partly, the temperature range from 1 K to 25 K. The performance of the thermometers was checked by comparison with the ITS-90 at various arbitrary temperatures. Two reference points served as highly stable and well characterized references, the superfluid lambda transition in 4He (O-point) at 2.1768 K and the Ne triple point at 24.5561 K. With pMFFT and CBT we also demonstrated a smooth overlap between the PLTS-2000 range below 1 K and the ITS-90 range above 1 K. All the investigated primary thermometers proved to be very practical alternatives to the established thermometric methods of the ITS-90 in the range below 25 K.
| Original language | English |
|---|---|
| Article number | 020003 |
| Journal | AIP Conference Proceedings |
| Volume | 3230 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 18 Oct 2024 |
| MoE publication type | A4 Article in a conference publication |
| Event | 10th International Temperature Symposium on Temperature: Its Measurement and Control in Science and Industry, ITS 2023 - Anaheim, United States Duration: 3 Apr 2023 → 7 Apr 2023 |
Funding
The research reported here has received funding from the EMPIR programme as an integrated part of Horizon 2020, the European Union\u2019s Framework Programme for Research and Innovation grant number 18SIB02 Real-K.