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A New Approach to Johnson Noise Thermometry Using a Quantum Voltage Noise Source for Calibration



Sae Woo Nam, Samuel Benz, Paul Dresselhaus, Weston L. Tew, David R. White, John M. Martinis


We describe a new approach to Johnson Noise Thermometry (JNT) that addresses certain limitations found in the conventional approach. The concept takes advantage of recent advances in digital synthesis and signal processing techniques together with advances in Josephson voltage standards. By using the perfect quantization fo voltages from the Josephson effect, a synthesized broadband waveform can be used as a calculable noise source for calibrations. A collaboration between NIST and the MSI explores this approach with the initial goal of creating a JNT measurement system capable of achieving relative accuracies of 0.001% in the range of temperatures between 84K and 430K. In this paper, we discuss the use of a broadband Josephson waveform generator to produce a calculable reference noise source, the related metrological challenges, the technical advantages conveyed by this approach, and the commensurate opportunities to advance the state of the field.
Proceedings Title
Proc., Conference on Precision Electromagnetic Measurements (CPEM)
Conference Dates
June 16-21, 2002
Conference Location
Ottawa, 1, CA


correlation, Johnson noise, Josephson junction, Nyquist, temperature, thermometry, voltage standard, waveform synthesis


Nam, S. , Benz, S. , Dresselhaus, P. , Tew, W. , White, D. and Martinis, J. (2002), A New Approach to Johnson Noise Thermometry Using a Quantum Voltage Noise Source for Calibration, Proc., Conference on Precision Electromagnetic Measurements (CPEM), Ottawa, 1, CA, [online], (Accessed April 20, 2024)
Created May 31, 2002, Updated October 12, 2021