Assumpcao Daniel, Renaud Dylan, Baradari Aida, Zeng Beibei, De-Eknamkul Chawina, Xin C J, Shams-Ansari Amirhassan, Barton David, Machielse Bartholomeus, Loncar Marko
John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
AWS Center for Quantum Networking, Boston, MA, USA.
Nat Commun. 2024 Dec 2;15(1):10459. doi: 10.1038/s41467-024-54541-2.
Practical quantum networks will require multi-qubit quantum nodes. This in turn will increase the complexity of the photonic circuits needed to control each qubit and require strategies to multiplex memories. Integrated photonics operating at visible to near-infrared (VNIR) wavelength range can provide solutions to these needs. In this work, we realize a VNIR thin-film lithium niobate (TFLN) integrated photonics platform with the key components to meet these requirements, including low-loss couplers (<1 dB/facet), switches (>20 dB extinction), and high-bandwidth electro-optic modulators (>50 GHz). With these devices, we demonstrate high-efficiency and CW-compatible frequency shifting (>50% efficiency at 15 GHz), as well as simultaneous laser amplitude and frequency control. Finally, we highlight an architecture for multiplexing quantum memories and outline how this platform can enable a 2-order of magnitude improvement in entanglement rates over single memory nodes. Our results demonstrate that TFLN can meet the necessary performance and scalability benchmarks to enable large-scale quantum nodes.
实用的量子网络将需要多量子比特量子节点。这反过来又会增加控制每个量子比特所需的光子电路的复杂性，并需要复用存储器的策略。在可见光到近红外（VNIR）波长范围内工作的集成光子学可以为这些需求提供解决方案。在这项工作中，我们实现了一个VNIR薄膜铌酸锂（TFLN）集成光子学平台，该平台具备满足这些要求的关键组件，包括低损耗耦合器（<1 dB/面）、开关（>20 dB消光）和高带宽电光调制器（>50 GHz）。利用这些器件，我们展示了高效且与连续波兼容的频率转换（在15 GHz时效率>50%），以及同时进行激光幅度和频率控制。最后，我们重点介绍了一种复用量子存储器的架构，并概述了该平台如何能够在纠缠率方面比单个存储器节点实现两个数量级的提升。我们的结果表明，TFLN能够满足实现大规模量子节点所需的性能和可扩展性基准。
