  The variational quantum eigensolver (VQE) is a promising candidate that
brings practical benefits from quantum computing. However, the required
bandwidth in/out of a cryostat is a limiting factor to scale cryogenic quantum
computers. We propose a tailored counter-based module with single flux quantum
circuits in 4-K stage which precomputes a part of VQE calculation and reduces
the amount of inter-temperature communication. The evaluation shows that our
system reduces the required bandwidth by 97%, and with this drastic reduction,
total power consumption is reduced by 93% in the case where 277 VQE programs
are executed in parallel on a 10000-qubit machine.
