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Conference on Precision Electromagnetic Measurements

Real-time quantum-accurate voltage waveform synthesis

Jane Ireland, Stephen Protheroe, Jonathan M. J. Williams, Allan Belcher, Ronald Dekker, Kars Schaapman, Ricardo Iuzzolino, Rodrigo A. Melo, Bruno Valinoti, Marcos Eduardo Bierzychudek, Martin Šíra, Jonas Herick, Oliver Kieler, Ralf Behr

Published Aug 1, 2020• 3 citations

Abstract

A pulse drive system capable of converting an arbitrary input signal into a delta sigma encoded pulse code stream in real time has been demonstrated. This system is based on the use of analog and digital hardware controlled by a Field Programmable Gate Array (FPGA) rather than using software to produce the delta sigma code and then loading it into the memory of a commercial Pulse Pattern Generator (PPG). The results of using the system to drive a Josephson junction array to synthesize quantum-accurate voltage waveforms are presented. The advantage of such a system includes the significant reduction in time required to change waveform parameters. This provides an easily tunable source of high-fidelity stable voltage waveforms at low temperature for future applications including validation of components for use in quantum technologies.

DOI: 10.1109/cpem49742.2020.9191715

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