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Development of a Quantum-Voltage-Calibrated Noise Thermometer at NIM
Published
Author(s)
Jifeng Qu, Samuel Benz, Jianqiang Zhang, Horst Rogalla, Yang Fu, Alessio Pollarolo, Jintao Zhang
Abstract
A quantum-voltage-calibrated Johnson-noise thermometer was developed at NIM, which measures the Boltzmann constant k through comparing the thermal noise across a 100 sense resistor at the temperature of the triple point water to the comb-like 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 results in a relative offset of 0.5x10^-6 from the current CODATA value of k, and a type A relative standard uncertainty of 23x10^-6. Benefiting from closely matched noise power and transmission line impedances, small nonlinearities in the cross-correlation electronics, and some other possible reasons, the derived k shows self-consistent values and standard uncertainties for different measurement bandwidths.
Proceedings Title
Temperature: Its Measurement and Control in Science and Industry, Vol. 8
Qu, J.
, Benz, S.
, Zhang, J.
, Rogalla, H.
, Fu, Y.
, Pollarolo, A.
and Zhang, J.
(2013),
Development of a Quantum-Voltage-Calibrated Noise Thermometer at NIM, Temperature: Its Measurement and Control in Science and Industry, Vol. 8, Anaheim, CA, US, [online], https://doi.org/10.1063/1.4821369, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=910779
(Accessed October 11, 2025)