Improvements in the Boltzmann constant measurement with noise thermometry at NIM

Author

Jifeng Qu ; Kunli Zhou ; Yunfeng Fu ; Rogalla, Horst ; Benz, Samuel P.

Author_Institution

Nat. Inst. of Metrol. (NIM), Beijing, China

fYear

2014

fDate

24-29 Aug. 2014

Firstpage

28

Lastpage

29

Abstract

Since 2010 we have been developing a quantum-voltage-calibrated Johnson noise thermometer at NIM to measure the Boltzmann constant k. With recent improvements in grounding and shielding of the electronics, and matching of the noise sources and transmission lines, the effects of electromagnetic interference and variations of fitting parameters with different bandwidths were greatly reduced. By combining 14 measurements with about 10 hours integrating period for each measurement, the relative standard uncertainties of 6.5×10^-6 and 2.8×10^-6 were achieved from statistics and bandwidth fit variations, respectively.

Keywords

calibration; constants; electromagnetic interference; measurement standards; measurement uncertainty; temperature measurement; thermal noise; voltage measurement; Boltzmann constant k measurement; NIM; bandwidth fit variation; electromagnetic interference; electronics grounding; electronics shielding; measurement standard; measurement uncertainty; noise source matching; noise thermometry; quantum-voltage-calibrated Johnson noise thermometer; transmission line matching; Bandwidth; Fitting; Measurement uncertainty; Noise; Noise measurement; Transmission line measurements; Voltage measurement; Boltzmann constant; Correlation; Josephson arrays; Noise; Quantization; Thermometry;

fLanguage

English

Publisher

ieee

Conference_Titel

Precision Electromagnetic Measurements (CPEM 2014), 2014 Conference on

Conference_Location

Rio de Janeiro

ISSN

0589-1485

Print_ISBN

978-1-4799-5205-2

Type

conf

DOI

10.1109/CPEM.2014.6898242

Filename

6898242