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Johnson Noise Thermometry Measurement of the Boltzmann Constant with a 200 Ohm Sense Resistor



Alessio Pollarolo, Tae H. Jeong, Samuel Benz, Horst Rogalla


In 2010, NIST measured the Boltzmann constant k with an electronic technique that measured the Johnson noise of a 100 Ω resistor at the triple point of water (TPW) and used a voltage waveform synthesized with a quantized voltage noise source (QVNS) as a reference. In this paper, we present measurements of k using a 200 Ω sense resistor and an appropriately modified QVNS circuit and waveform. Preliminary results show agreement with the previous value within the statistical uncertainty. Analysis is presented that identifies the largest source of uncertainty, which is the frequency dependence in the linear term of the two-parameter fit.
IEEE Transactions on Instrumentation and Measurement


Boltzmann equation, Josephson junction, measurement units, noise measurement, standards, temperature.


Pollarolo, A. , Jeong, T. , Benz, S. and Rogalla, H. (2013), Johnson Noise Thermometry Measurement of the Boltzmann Constant with a 200 Ohm Sense Resistor, IEEE Transactions on Instrumentation and Measurement, [online],, (Accessed May 26, 2024)


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Created May 31, 2013, Updated October 12, 2021