近日，美国耶鲁大学Tang, Hong X.团队报道了一条1公里长的光子链路，连接两个稀释冰箱中的超导电路。2026年3月10日出版的《自然—光子学》杂志发表了这项成果。
超导量子处理器是实现实用量子计算算法的主要平台之一。尽管目前已经实现了包含数百个量子比特的超导量子处理器，但其进一步扩展受到稀释制冷机物理尺寸和制冷功率的限制。通过构建量子网络连接不同制冷机中的量子比特可以突破这一限制，这需要微波-光波转换器实现长距离低损耗信号传输。虽然各类设计方案已实现高效低噪声的转换器，但迄今尚未在不同制冷机之间建立相干光子链路。
研究组实验演示了两个独立稀释制冷机中超导电路之间的相干信号传输，该传输通过一对频率匹配的氮化铝电光转换器实现，中间由1公里长的通信光纤连接。通过非对称光子分子设计实现了两个转换器之间的光频匹配，转换效率较商用电光调制器整体提升80分贝，为构建全量子化链路奠定了基础。这项工作为通过光子链路互联的可扩展超导量子网络提供了关键设计准则。
附：英文原文
Title: A 1-km photonic link connecting superconducting circuits in two dilution refrigerators
Author: Zhou, Yiyu, Wu, Yufeng, Li, Chunzhen, Shen, Mohan, Yang, Likai, Xie, Jiacheng, Tang, Hong X.
Issue&Volume: 2026-03-10
Abstract: Superconducting quantum processors are a leading platform for implementing practical quantum computation algorithms. Although superconducting quantum processors with hundreds of qubits have been demonstrated, their further scale-up is constrained by the physical size and cooling power of dilution refrigerators. This constraint can be overcome by constructing a quantum network to interconnect qubits hosted in different refrigerators, which requires microwave-to-optical transducers to enable low-loss signal transmission over long distances. Although various designs and demonstrations have achieved high-efficiency and low-added-noise transducers, a coherent photonic link between separate refrigerators has not yet been realized. Here we experimentally demonstrate coherent signal transfer between two superconducting circuits housed in separate dilution refrigerators, enabled by a pair of frequency-matched aluminium nitride electro-optic transducers connected via a 1-km telecom optical fibre. The optical frequency matching between two transducers is realized by an asymmetric photonic molecule design, and an overall 80dB improvement in transduction efficiency over commercial electro-optic modulators is achieved, paving the way towards a fully quantum-enabled link. This work provides critical design guidelines for scalable superconducting quantum networks interconnected by photonic links.
DOI: 10.1038/s41566-026-01866-7
Source: https://www.nature.com/articles/s41566-026-01866-7