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arXiv · 1501.00195

Improved electronic measurement of the Boltzmann constant by Johnson noise Thermometry

Jifeng Qu·Samuel P Benz·Alessio Pollarolo·Horst Rogalla·Weston L Tew·Rod White·Kunli Zhou
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Abstract

The unit of thermodynamic temperature, the kelvin, will be redefined in 2018 by fixing the value of the Boltzmann constant, k. The present CODATA recommended value of k is determined predominantly by acoustic gas-thermometry results. To provide a value of k based on different physical principles, purely electronic measurements of k were performed by using a Johnson noise thermometer to compare the thermal noise power of a 200 Ohm sensing resistor immersed in a triple-point-of-water cell to the noise power of a quantum-accurate pseudo-random noise waveform of nominally equal noise power. Measurements integrated over a bandwidth of 550 kHz and a total integration time of 33 days gave a measured value of k = 1.3806514(48)x10^-23 J/K, for which the relative standard uncertainty is 3.5x10^-6 and the relative offset from the CODATA 2010 value is +1.9x10^-6.

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Jifeng Qu, Samuel P Benz, Alessio Pollarolo, Horst Rogalla, Weston L Tew, Rod White, Kunli Zhou. 2014-12-31. Improved electronic measurement of the Boltzmann constant by Johnson noise Thermometry. https://doi.org/10.1088/0026-1394%2F52%2F5%2Fs242

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