Standard reference materials: srm 768: temperature reference standard for use below 0. 5 k

Technical Report · Sun Apr 01 04:00:00 EST 1979

OSTI ID:5507455

Stolen, Jr, R J; Dove, R B

Cryogenic temperature scales are now available (viz., the newly created EPT-76) which are quite accurate and which extend deep into the cryogenic region (as low as 0.5 K). It is the region below 0.5 K where no formal scale exists which is of concern here. By developing a compact device which provides five reference temperatures from 0.015 K to 0.21 K, the authors hope to provide a lingua franca by which experimental results of different laboratories involving the parameter temperature may be meaningfully compared. Such a device, designated SRM 768, is now available and consists of a self-contained assembly of coils and five samples which can be used to provide in situ temperature calibration. Simple room temperature electronics readily permit the observation of the five narrow and highly reproducible superconducting phase transitions. These phase transitions have been assigned temperature values by means of fundamental thermometers used at the National Bureau of Standards. Provided that care is exercised in reducing the magnetic field acting upon the device, the user can confidently expect to achieve a temperature reproducibility and traceability to the NBS temperature scale of plus or minus 0.3 mK.

• Research Organization: National Bureau of Standards, Washington, DC (USA). Center for Absolute Physical Quantities
• OSTI ID: 5507455
• Report Number(s): PB-294245
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CALIBRATION STANDARDS
CRYOGENICS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
PHYSICAL PROPERTIES
STANDARDS
SUPERCONDUCTIVITY
TEMPERATURE MEASUREMENT
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE