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Title: Development of a quantum-voltage-calibrated noise thermometer at NIM

A quantum-voltage-calibrated Johnson-noise thermometer was developed at NIM, which measures the Boltzmann constant k by comparing the thermal noise across a 100 Ω sense resistor at the temperature of the triple point of water with the pseudo-random frequency-comb voltage waveform synthesized with a bipolar-pulse-driven quantum-voltage-noise source. A measurement with integration period of 10 hours and bandwidth of 640 kHz resulted in a relative offset of 0.5×10{sup −6} from the current CODATA value of k, and a type A relative standard uncertainty of 23×10{sup −6}. Benefiting from closely matched noise powers and transmission-line impedances and small nonlinearities in the cross-correlation electronics, the derived k shows self-consistent values and standard uncertainties for different measurement bandwidths.
Authors:
; ;  [1] ; ; ;  [2]
  1. National Institute of Metrology, Beijing 100013, P. R. (China)
  2. National Institute of Standards and Technology, Boulder, CO 80305 (United States)
Publication Date:
OSTI Identifier:
22218019
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1552; Journal Issue: 1; Conference: 9. international temperature symposium, Los Angeles, CA (United States), 19-23 Mar 2012; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; COMPARATIVE EVALUATIONS; CORRELATIONS; ELECTRIC POTENTIAL; IMPEDANCE; NOISE; NOISE THERMOMETERS; NONLINEAR PROBLEMS; RANDOMNESS; RESISTORS; SUPERCONDUCTING JUNCTIONS; TRIPLE POINT; WATER; WAVE FORMS