Current Status and Issues of Cryogenic Implementations and Technologies for Quantum Computers

Abstract

Installing semi-rigid coaxial cables and microwave components in a dilution refrigerator is essential to readout and control superconducting quantum processors. Here we discuss passive and active heat loads generated in the refrigerator and explain techniques to minimize them. Scaling up the size and cooling power of the refrigerator is required in order to operate largely integrated superconducting processors. We also discuss problems impeding the scale up of the refrigerators in Japan and activities in the world.