清华大学张巍团队近日研究了12.3公里光纤上的片对片光子量子隐形传态。2025年7月9日出版的《光：科学与应用》杂志发表了这项成果。

量子隐形传态是量子网络中的一项重要功能。利用量子光子电路可以大大简化光子量子隐形传态的实现。为了延长芯片间的隐形传态距离，需要在芯片设计和系统实现上付出更多的努力。

研究组展示了在星形拓扑量子网络场景下，基于时间盒的光纤上的片对片光子量子隐形传态。在单个芯片上设计和制造了三个量子光子电路，每个电路都有特定的功能：主节点的预告单光子产生，中继节点的纠缠光子对产生和BSM，以及中心节点的隐形传输光子的投影测量。

在这些量子光子电路中，研究组对用于时间盒编码的非平衡马赫-曾德尔干涉仪（UMZI）进行了优化，以减少插入损耗并抑制芯片上产生的噪声光子。此外，采用有源反馈系统抑制电路间光纤长度波动的影响，实现了中继节点BSM的稳定量子干扰。因此，光纤上的光子量子隐形传态速度为12.3Km是基于这些量子光子电路实现的，显示了芯片集成对量子网络发展的潜力。

附：英文原文

Title: Chip-to-chip photonic quantum teleportation over optical fibers of 12.3km

Author: Liu, Dongning, Jin, Zhanping, Liu, Jingyuan, Zou, Xiaotong, Ren, Xiaosong, Li, Hao, You, Lixing, Feng, Xue, Liu, Fang, Cui, Kaiyu, Huang, Yidong, Zhang, Wei

Issue&Volume: 2025-07-09

Abstract: Quantum teleportation is a crucial function in quantum networks. The implementation of photonic quantum teleportation could be highly simplified by quantum photonic circuits. To extend chip-to-chip teleportation distance, more effort is needed on both chip design and system implementation. In this work, we demonstrate a time-bin-based chip-to-chip photonic quantum teleportation over optical fibers under the scenario of a star-topology quantum network. Three quantum photonic circuits are designed and fabricated on a single chip, each serving specific functions: heralded single-photon generation at the user node, entangled photon pair generation and BSM at the relay node, and projective measurement of the teleported photons at the central node. The unbalanced Mach–Zehnder interferometers (UMZI) for time-bin encoding in these quantum photonic circuits are optimized to reduce insertion losses and suppress noise photons generated on the chip. Besides, an active feedback system is employed to suppress the impact of fiber length fluctuation between the circuits, achieving a stable quantum interference for the BSM in the relay node. As a result, a photonic quantum teleportation over optical fibers of 12.3km is achieved based on these quantum photonic circuits, showing the potential of chip integration for the development of quantum networks.

DOI: 10.1038/s41377-025-01920-z

Source: https://www.nature.com/articles/s41377-025-01920-z