Encoding and processing quantum information in the time-of-arrival of photons offer significant advantages for quantum information science and technology. These advantages include ease of experimental realization, robustness over photon state transmission, and compatibility with existing telecommunication infrastructure. Additionally, time-of-arrival encoding has the potential for high-rate quantum communication and holds promise for the future development of quantum internet. This review explores the generation, processing, and applications of time-encoded quantum states, focusing on both single-photon states, energy–time entanglement, and time-bin entanglement. We summarize the nonlinear optics platforms and advanced laser and modulation techniques utilized for photon sources that enable quantum information encoding onto the photons' time-of-arrival. We also highlight advanced quantum state processing methods in the time domain, including the Franson interferometry, optical switch-based schemes, and state-of-the-art measurement and detection schemes that allow for high-speed and multi-dimensional quantum operations. Finally, we review the mainstream implementations mainly including the quantum communication demonstrations and outline future directions for developing practical quantum networks leveraging time-encoded photon states.

中文翻译：

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时间编码光子量子态：生成、处理和应用


在光子到达时对量子信息进行编码和处理为量子信息科学和技术提供了显著的优势。这些优势包括易于实验实现、比光子状态传输更稳健以及与现有电信基础设施的兼容性。此外，到达时间编码具有高速量子通信的潜力，并为量子互联网的未来发展带来了希望。本文探讨了时间编码量子态的生成、处理和应用，重点介绍了单光子态、能量-时间纠缠和时间-bin 纠缠。我们总结了用于光子源的非线性光学平台以及先进的激光和调制技术，这些技术能够将量子信息编码到光子的到达时间上。我们还重点介绍了时域中的高级量子态处理方法，包括 Franson 干涉测量法、基于光学开关的方案以及允许高速和多维量子运算的最先进的测量和检测方案。最后，我们回顾了主要包括量子通信演示的主流实现，并概述了利用时间编码光子态开发实用量子网络的未来方向。