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Thermometry metrology

News and Updates

Hooked on Photonics? Math to the Rescue

Photonic thermometers – which measure temperature using light – have been around in optical fiber form for decades. These devices, called fiber Bragg gratings

Projects and Programs

Johnson Noise Thermometry

Johnson noise thermometry (JNT) is a primary temperature measurement technique based on the fundamental properties of thermal fluctuations in conductors. We

Atomic Standard for Pressure

NIST scientists are developing a highly accurate primary standard for pressure in the range 2 MPa to 7 MPa based on fundamental physical properties of helium


Low temperatures suppress noise and make quantum phenomena accessible. As a result, cryogenics play a crucial role in precision measurements.


2022 Update for the Differences Between Thermodynamic Temperature and ITS 90 Below 335 K

Christof Gaiser, Bernd Fellmuth, Roberto Maria Gavioso, Murat Kalemci, Vladimir Kytin, Tohru Nakano, Laurent Pitre, Anatoli Pokhodun, Patrick Rourke, Richard Rusby, Peter P.M. Steur, Weston L. Tew, Robin James Underwood, Rod White, Inseok Yang, Jintao Zhang
In 2011, a working group of the Consultative Committee for Thermometry published best estimates of the differences between thermodynamic temperature (T) and the

Emerging technologies in the field of thermometry

Zeeshan Ahmed, Graham Machin, Sergey Dedyulin
The past decade saw the emergence of new temperature sensors that have the potential to disrupt a century-old measurement infrastructure based on resistance

Tools and Instruments