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arXiv:2512.24926 · 中国科学通报：英文版

High-performance quantum interconnect between bosonic modules beyond transmission loss constraints

Hongwei Huang, Jie Zhou, Weizhou Cai, Weiting Wang, Yilong Zhou, Yunlai Zhu, Ziyue Hua, Yifang Xu, Lida Sun, Juan Song, Tang Su, Ming Li, Haifeng Yu, Chang-Ling Zou, Luyan Sun

quant-phSubmitted Dec 31, 2025• Announced Jan 1, 2026• 0 citations
arXivHTMLPDF

Abstract

Distributed quantum computing architectures require high-performance quantum interconnects between quantum information processing units, while previous implementations have been fundamentally limited by transmission line losses. Here, we demonstrate a low-loss interconnect between two superconducting modules using an aluminum coaxial cable, achieving a bus mode quality factor of 1.7e6. By employing SNAIL as couplers, we realize inter-modular state transfer in 0.8 μs via a three-wave mixing process. The state transfer fidelity reaches 98.2% for quantum states encoded in the first two energy levels, achieving a Bell state fidelity of 92.5%. Furthermore, we show the capability to transfer high-dimensional states by successfully transmitting binomially encoded logical states. Systematic characterization reveals that performance constraints have shifted from transmission line losses (contributing merely 0.2% infidelity) to module-channel interface effects and local Kerr nonlinearities. Our work advances the realization of quantum interconnects approaching fundamental capacity limits, paving the way for scalable distributed quantum computing and efficient quantum communications.

Journal reference
Science Bulletin 71, 3544 (2026)
DOI
10.1016/j.scib.2026.06.027

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