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TitleAn electronic measurement of the Boltzmann constant
Publication TypeJournal Article
Year of Publication2011
AuthorsBenz, S.P., Pollarolo A., Qu J., Rogalla H., Urano C., Tew W.L., Dresselhaus P.D., and White D.R.
Pagination142 - 153
Date Published2011
ISSN00261394 (ISSN)
KeywordsBoltzmann constants, Combined uncertainty, Electromagnetic interference effect, Electromagnetic pulse, Electronic measurements, Electronic technique, Johnson noise, Josephson-junction, Relative combined uncertainty, Statistical uncertainty, Systematic errors, Thermometers, Triple point of waters, Uncertainty analysis, Uncertainty budget, Voltage reference, Waveform synthesizer
AbstractThe Boltzmann constant k was measured by comparing the Johnson noise of a resistor at the triple point of water with a quantum-based voltage reference signal generated with a superconducting Josephson-junction waveform synthesizer. The measured value of k = 1.380 651(17) × 10 -23 J K -1 is consistent with the current CODATA value and the combined uncertainties. This is our first measurement of k with this electronic technique, and the first noise-thermometry measurement to achieve a relative combined uncertainty of 12 parts in 10 6. We describe the most recent improvements to our Johnson-noise thermometer that enabled the statistical uncertainty contribution to be reduced to seven parts in 10 6, as well as the further reduction of spurious systematic errors and electromagnetic interference effects. The uncertainty budget for this measurement is discussed in detail. © 2011 BIPM & IOP Publishing Ltd.

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