Journal of Physics Conference Series

Sub-Kelvin single flux quantum control circuits and multi-chip packaging for supporting superconducting qubit

Shinichi Yorozu, Toshiyuki Miyazaki, Vasili K. Semenov, Yasunobu Nakamura, Y. Hashimoto, K. Hinode, Tomoyuki Sato, Y Kameda, Jaw-Shen Tsai

Published Jun 1, 2006• 3 citations

Publisher

Abstract

Superconducting single flux quantum (SFQ) circuit can operate at very low temperature. This is suitable for controlling a quantum computing system with Josephson junctions. However, it is difficult to integrate both SFQ circuits and qubits into a single-chip, because of the dissipative characteristics of SFQ circuits. Therefore, we have developed a multi-chip packaging technology for a qubit control module. The module consists of SFQ circuit chips, qubit chips, and a substrate all of which are fabricated with Nb and Al technology. The chips are flip-chip bonded with superconducting solder bumps. We also investigated SFQ control circuits for superconducting qubits and circuit parameter optimization for sub-Kelvin temperature operation. Using both multi-chip packaging and optimized SFQ control circuit makes the design of qubit control module more flexible.

DOI: 10.1088/1742-6596/43/1/347

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