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Publication Citation: An electronic measurement of the Boltzmann constant

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Author(s): Samuel P. Benz; Alessio Pollarolo; Jifeng Qu; Horst Rogalla; Chiharu Urano; Weston L. Tew; Paul D. Dresselhaus; D. R. White;
Title: An electronic measurement of the Boltzmann constant
Published: March 30, 2011
Abstract: The Boltzmann constant 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 = 1.380651(18)×10^23 J/K 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 13 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 EMI effects. The uncertainty budget for this measurement is discussed in detail.
Citation: Metrologia
Volume: 48
Pages: pp. 142 - 153
Keywords: Boltzmann equation; Correlation; Digital-analog conversion; Josephson arrays; Measurement units; Noise Measurement; Quantization; Signal synthesis; Standards; Temperature.
Research Areas: Electronic Temperature Standard, Johnson Noise Thermometry, SI (Thermodynamics Units), Quantum Electrical Measurements
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