Electrical Drive of a Josephson Junction Array using a Cryogenic BiCMOS Pulse Pattern Generator: Towards a Fully Integrated Josephson Arbitrary Waveform Synthesizer

We combine a cryogenic BiCMOS integrated circuit, which generates high-speed return-to-zero (RTZ) pulses, with a superconducting Josephson junction array. The BiCMOS circuit acts as a cryogenic pulse pattern generator, delivering data rates of 30 Gb/s, while consuming 302 mW at 4 K. Each electrical pulse of the serializer effectively transfers one magnetic flux quantum through every Josephson junction, so that the average output voltage of the array produces well-defined plateaus (Shapiro steps) in its current-to-voltage characteristic. To the best of our knowledge, this is the first integration of a Josephson junction array with a cryogenic BiCMOS chip. The presented results pave the way toward a hybrid and fully integrated Josephson arbitrary waveform synthesizer (JAWS) that can generate ultra-low-noise signals for quantum voltage metrology and quantum information systems.