Current Status and Issues of Superconductor Peripheral Circuits for Quantum Computers

Abstract

Superconductor devices are promising for building large-scale quantum computing systems. This article reports the current status and issues of the superconductor classical (digital and mixed-signal) circuit technology for quantum computing applications. The single-flux-quantum-based circuits provide advanced signal processing featuring several gigahertz clock frequencies, high sensitivity, and ultra-low power operation at a millikelvin-level temperature and are helpful for control and readout of quantum bits. The superconductor cryogenic peripheral circuits are expected to be a key to breakthrough in system scalability.