Survey on Cryogenic CMOS Circuits for Quantum Computers

Abstract

Nowadays, quantum computers are attracting much interest. In current quantum computers, measurement instruments, which provide functions of controlling and reading out quantum bits (qubits), operate under room temperature, and the instruments and qubits are connected by cables. This means that many cables are required for large-scale quantum computers, which could cause scalability issue. To reduce such cables, various CMOS LSIs operating at cryogenic temperature have been proposed for controlling and reading out qubits. In this paper, I briefly introduce characteristics of transistor and passive devices, such as resistors, capacitors, and inductors, at cryogenic temperature. Then, I review the latest research on cryogenic CMOS circuits for quantum computers.