Rare-earth (RE) ion doped crystalline materials have a wide spectrum of applications in lasers, amplifiers, sensors, as well as classical and quantum information processing. The incorporation of RE ions into integrated photonics holds great promise for enriching the designer's toolbox with a view to addressing key performance features not available in existing photonic integration platforms. RE-ion-doped thin-film LiNbO₃ (also called RE-ion-doped lithium-niobate-on-insulator, RE:LNOI), which inherits nearly all the material advantages as well as nanophotonic integration from the LNOI technology, meets the urgent demands for chip-integrated laser sources, optical amplifiers, and quantum memories based on LNOI photonics. In this article, a timely review is provided on the development of RE:LNOI photonics in terms of ion-doping techniques, chip-integrated lasers, and amplifiers, as well as low-temperature optical characterizations for quantum photonics. To conclude, some well-noted topics that may shape the future directions in lithium–niobate integrated photonics are discussed.

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基于稀土离子掺杂薄膜铌酸锂的集成光子学

稀土 (RE) 离子掺杂晶体材料在激光器、放大器、传感器以及经典和量子信息处理中具有广泛的应用。将稀土离子结合到集成光子学中为丰富设计人员的工具箱提供了巨大的希望，以解决现有光子集成平台中不可用的关键性能特征。RE离子掺杂薄膜LiNbO ₃（也称为RE离子掺杂铌酸锂绝缘体，RE:LNOI），继承了LNOI技术几乎所有的材料优势以及纳米光子集成，满足了芯片集成激光源、光学的迫切需求。放大器和基于 LNOI 光子学的量子存储器。本文及时回顾了 RE:LNOI 光子学在离子掺杂技术、芯片集成激光器和放大器方面的发展，以及量子光子学的低温光学表征。最后，讨论了一些可能塑造铌酸锂集成光子学未来方向的知名主题。