Title :
Improvements in the NIST Johnson noise thermometry system
Author :
Benz, S.P. ; Rogalla, H. ; White, D.R. ; Qu, Jifeng ; Dresselhaus, P.D. ; Tew, W.L. ; Nam, S.W.
Author_Institution :
Nat. Inst. of Stand. & Technol., Boulder, CO, USA
Abstract :
We have developed a Johnson noise thermometry system that is calibrated by precision waveforms synthesized with a quantized voltage noise source (QVNS). Significant improvements to the QVNS and the cross-correlation measurement electronics have dramatically reduced systematic errors and measurement uncertainty. We describe some of these improvements and discuss the potential for this system to contribute to the redefinition of the Boltzmann constant.
Keywords :
constants; thermal noise; thermometers; Boltzmann constant; Johnson noise thermometry system; calibration; cross-correlation measurement electronics; precision waveforms; quantized voltage noise source; Electric variables measurement; Measurement standards; NIST; Noise measurement; Resistors; Superconducting transmission lines; Temperature measurement; Thermodynamics; Voltage; Wires;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 2008. CPEM 2008. Conference on
Conference_Location :
Broomfield, CO
Print_ISBN :
978-1-4244-2399-6
Electronic_ISBN :
978-1-4244-2400-9
DOI :
10.1109/CPEM.2008.4574640
