Jitter Sensitivity Analysis of the Superconducting Josephson Arbitrary Waveform Synthesizer

Area of Science:

• Electrical Engineering
• Metrology
• Superconducting Electronics

Background:

• Accurate waveform generation is crucial for radio frequency (RF) metrology.
• Superconducting digital-to-analog converters (DACs) offer potential for high-precision waveform synthesis.

Purpose of the Study:

• To perform the first jitter sensitivity analysis of a superconducting voltage reference waveform synthesizer.
• To quantify the impact of random and deterministic pulse position jitter (PPJ) on amplitude accuracy and signal-to-noise and distortion ratio (SNDR).

Main Methods:

• Analysis of a 1.5-bit delta-sigma DAC operating at 28 GHz.
• Quantification of PPJ effects on fundamental tone amplitude and in-band SNDR.
• Simulations (100 kHz-1 GHz) and experiments (100 kHz-3 MHz) to verify jitter impacts.

Main Results:

• Random PPJ up to 200 fs rms has negligible impact on accuracy and SNDR for tones up to 1 GHz.
• Deterministic PPJ, caused by nonzero DC bias current, degrades in-band SNDR by up to 30 dB at 1 GHz.
• Superconducting DACs exhibit no output pulsewidth jitter.

Conclusions:

• Superconducting DACs are robust against random jitter for high-frequency waveform synthesis.
• Deterministic jitter must be mitigated to ensure the accuracy of superconducting waveform synthesizers.
• This work establishes a new paradigm for RF metrology using accurate reference waveform sources.