Rübeling Philip, Heine Jan, Johanning Robert, Kues Michael
Institute of Photonics (IOP), Leibniz University Hannover, Nienburger Straße 17, 30167 Hannover, Germany.
Cluster of Excellence PhoenixD (Photonics, Optics, and Engineering - Innovation Across Disciplines), Leibniz University Hannover, Welfengarten 1, 30167 Hannover, Germany.
Sci Adv. 2024 Jul 26;10(30):eadn8907. doi: 10.1126/sciadv.adn8907.
Fiber-optical networks are well established to accommodate global data traffic via coherent information transmission. The next generation of telecommunications will require the integration of quantum information into fiber-optic networks, e.g., for quantum key distribution. A promising and scalable route to enable quantum networking is encoding quantum information into the frequency of photons. While the cointegration of frequency-entangled photons with coherent information transmission is achieved via spectral multiplexing, more resource-efficient approaches are required. In this work, we introduce and experimentally demonstrate a transceiver concept that enables the transmission of coherent and frequency-entangled photons over a single-frequency channel. Our concept leverages the serrodyne technique via electro-optic phase modulation leading to very different dynamics for entangled and coherent photons. This enables temporal multiplexing of the respective signals. We demonstrate the preservation of entanglement over the channel in the presence of coherent light. Our approach reveals a strong potential for efficient bandwidth use in hybrid networks.
光纤网络已经成熟，能够通过相干信息传输来承载全球数据流量。下一代电信将需要把量子信息集成到光纤网络中，例如用于量子密钥分发。实现量子网络的一条有前景且可扩展的途径是将量子信息编码到光子的频率中。虽然通过频谱复用实现了频率纠缠光子与相干信息传输的共集成，但仍需要更具资源效率的方法。在这项工作中，我们介绍并通过实验证明了一种收发器概念，该概念能够在单频信道上传输相干和频率纠缠光子。我们的概念通过电光相位调制利用了锯齿波技术，这导致纠缠光子和相干光子具有非常不同的动力学特性。这使得能够对各自的信号进行时分复用。我们展示了在存在相干光的情况下通道上纠缠的保持。我们的方法揭示了在混合网络中高效利用带宽的强大潜力。
