Evaluation of a Josephson Arbitrary Waveform Synthesizer at Low Voltages for the Calibration of Lock-In Amplifiers

We have evaluated a Josephson arbitrary waveform synthesizer (JAWS) in the voltage range from 1 μV to 1 mV at frequencies from 60 to 1000 Hz for the use in the calibration of lock-in amplifiers. The uncertainty contribution from the JAWS system is 45 nV for 1 mV at 1000 Hz and k = 2.0. We anticipate that the JAWS will help extend the lower voltage and frequency range of ac voltage metrology and improve the uncertainties by one order of magnitude compared to conventional techniques.