  We demonstrate the operation of Josephson junction arrays (JJA) driven by
optical pulses generated by a mode-locked laser and an optical time-division
multiplexer. A commercial photodiode converts the optical pulses into
electrical ones in liquid helium several cm from the JJA. The performance of
our custom-made mode-locked laser is sufficient for driving a JJA with low
critical current at multiple Shapiro steps. Our optical approach is a potential
enabler for fast and energy-efficient pulse drive without expensive
high-bandwidth electrical pulse pattern generator, and without high-bandwidth
electrical cabling crossing temperature stages. Our measurements and
simulations motivate an improved integration of photodiodes and JJAs using,
e.g., flip-chip techniques, in order to improve both the understanding and
fidelity of pulse-driven Josephson Arbitrary Waveform Synthesizers (JAWS).
