Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

An AC Josephson Source for Johnson Noise Thermometry



Samuel Benz, John M. Martinis, Paul Dresselhaus, Sae Woo Nam


We have adapted the Josephson arbitrary waveform synthesizer to create a quantized voltage noise source suitable for calibrating the cross-correlation electronics of a Johnson noise thermometer system. The requirements of long term stability and low voltage amplitude allow dramatic simplification of the bias electronics compared to previous circuits. We describe the waveform synthesis, the bias technique and the superconducting integrated circuit used to generate the pseudo-noise waveforms.
IEEE Transactions on Instrumentation and Measurement


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


Benz, S. , Martinis, J. , Dresselhaus, P. and Nam, S. (2003), An AC Josephson Source for Johnson Noise Thermometry, IEEE Transactions on Instrumentation and Measurement, [online], (Accessed April 25, 2024)
Created March 31, 2003, Updated October 12, 2021