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Progress on Johnson Noise Thermometry using a Quantum Voltage Noise Source for Calibration



Sae Woo Nam, Samuel P. Benz, Paul D. Dresselhaus, Charles J. Burroughs, Weston L. Tew, D. R. White, John M. Martinis


We describe our progress towards a high-precision measurement of temperature using Johnson noise. Using a Quantized Voltage Noise Source (QVNS) based on the Josephson effect as a calculable noise source, we have been able to measure the ratio of the gallium and water triple-point temperatures to within an accuracy better than 100 ?K/K. We also describe the operation of our Johnson noise thermometry system that could be used as a primary thermometer and possible sources of error that limit our absolute temperature measurements to ~150 ?K/K.
IEEE Transactions on Instrumentation and Measurement


correlation, digital-analog conversion, frequency control, frequency synthesizers, Josephson junction arrays, noise, quantization, signal synthesis, standards, superconducting microwave devices, superconductor-normal-superconductor devices, temperature, temperature measurement, voltage control


Nam, S. , Benz, S. , Dresselhaus, P. , Burroughs, C. , Tew, W. , White, D. and Martinis, J. (2005), Progress on Johnson Noise Thermometry using a Quantum Voltage Noise Source for Calibration, IEEE Transactions on Instrumentation and Measurement, [online], (Accessed April 23, 2024)
Created April 1, 2005, Updated January 27, 2020