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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.|
|Pages:||pp. 142 - 153|
|Keywords:||Boltzmann equation, Correlation, Digital-analog conversion, Josephson arrays, Measurement units, Noise Measurement, Quantization, Signal synthesis, Standards, Temperature.|
|Research Areas:||Quantum Electrical Measurements, Johnson Noise Thermometry, Electronic Temperature Standard, SI (Thermodynamics Units)|
|PDF version:||Click here to retrieve PDF version of paper (555KB)|