Summary of the project

In order to realize a fault-tolerant universal quantum computer (FTQC), it is necessary to improve both "quality" and "quantity" aspects of quantum computers. The current development of quantum computers is dominated by “a bottom-up approach” that prioritizes "quality" of qubits and increases qubit number. In contrast, our project will take an opposite “top-down approach”. In other words, in order to take advantage of the advanced integration capability of silicon semiconductor technology (i.e., the ability to implement a large number of elements with uniform characteristics), we will promote a system design that emphasizes "quantity" from the beginning. Then we will develop various technologies (two-dimensional qubit arrays, cryogenic CMOS circuits and mounting systems, hot silicon qubits, digital correction, etc.), by use of highly integrated structures achievable for silicon devices, to improve the quality of silicon quantum computer system. Finally, we will realize the FTQC.