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Publication Citation: Flat frequency response in the electronic measurement of the Boltzmann constant

NIST Authors in Bold

Author(s): Jifeng Qu; Samuel P. Benz; Yang Fu; Jianqiang Zhang; Horst Rogalla; Alessio Pollarolo;
Title: Flat frequency response in the electronic measurement of the Boltzmann constant
Published: July 01, 2012
Abstract: A new quantum voltage calibrated Johnson noise thermometer (JNT) was developed at NIM to demonstrate the electrical approach that determines the Boltzmann constant k by comparing electrical and thermal noise power. A measurement with integration period of 10 hours and bandwidth of 640 kHz results in relative offset of 0.5106 from the current CODATA value of k, and type A relative standard uncertainty of 23106. The quadratic fitting parameters of the ratio spectrum show a flat frequency response with respect to the measurement bandwidth. This flat response is a dramatic improvement compared to the response produced by the NIST JNT system that dominated the relative combined uncertainty of previous measurements of k.
Conference: Conference on Precision Electromagnetic Measurements
Proceedings: Conference on Precision Electromagnetic Measurements Conference Digest
Volume: 28
Pages: pp. 216 - 217
Location: National Harbor, MD
Dates: July 1-6, 2012
Keywords: Boltzmann equation, Correlation, Digital-analog conversion, Josephson arrays, Measurement units, Noise Measurement, Quantization, Signal synthesis, Standards, Temperature
Research Areas: Quantum Electrical Measurements, Instrumentation, Quantum Devices, Measurements
DOI: http://dx.doi.org/10.1109/CPEM.2012.6250879  (Note: May link to a non-U.S. Government webpage)
PDF version: PDF Document Click here to retrieve PDF version of paper (208KB)