IEEE Transactions on Instrumentation and Measurement
An Optoelectronic Pulse Drive for Quantum Voltage Synthesizer
Jane Ireland, Jonathan M. J. Williams, Oliver Kieler, Ralf Behr, Ernest Houtzager, Ralph Hornecker, Helko E. van den Brom
Abstract
An optoelectronic pulse drive system based on commercially available telecoms optoelectronic components and a field-programmable gate array has been developed. In order to allow the use of ac-coupled optoelectronic components, a method of adding and subtracting complementary pulses was developed. The system was used to drive a Josephson junction array to synthesize quantum-accurate voltage waveforms. These waveforms will be used in voltage waveform metrology applications. Results from the synthesis of sinusoidal unipolar voltage waveforms from 3 to 300 kHz are presented. The margin of operation was measured and shown to require an optical pulse height stability better than 0.15 mW. The use of delta-sigma code with repeated sections, suitable for a quantum voltage digitizer was also examined. A test code corresponding to a delta-sigma feedback loop rate of 250 MHz was used to synthesize a 3.125 kHz sinusoidal waveform.