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arXiv · 2310.01630

Inter-temperature Bandwidth Reduction in Cryogenic QAOA Machines

Yosuke Ueno·Yuna Tomida·Teruo Tanimoto·Masamitsu Tanaka·Yutaka Tabuchi·Koji Inoue·Hiroshi Nakamura
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Abstract

The bandwidth limit between cryogenic and room-temperature environments is a critical bottleneck in superconducting noisy intermediate-scale quantum computers. This paper presents the first trial of algorithm-aware system-level optimization to solve this issue by targeting the quantum approximate optimization algorithm. Our counter-based cryogenic architecture using single-flux quantum logic shows exponential bandwidth reduction and decreases heat inflow and peripheral power consumption of inter-temperature cables, which contributes to the scalability of superconducting quantum computers.

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Yosuke Ueno, Yuna Tomida, Teruo Tanimoto, Masamitsu Tanaka, Yutaka Tabuchi, Koji Inoue, Hiroshi Nakamura. 2023-10-02. Inter-temperature Bandwidth Reduction in Cryogenic QAOA Machines. https://doi.org/10.1109/lca.2023.3322700

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