The ability to detect quantum superpositions lies at the heart of fundamental and applied aspects of quantum mechanics. The time-frequency degree of freedom of light enables encoding and transmitting quantum information in a multidimensional fashion compatible with fiber and integrated platforms. However, the ability to efficiently detect high-dimensional time-bin superpositions, a subset of encodings in the wider time-frequency paradigm, is not yet available. Here we show that multidimensional time-bin superpositions can be detected using a single time-resolved photon detector. Our approach uses off-the-shelf components and is based on the temporal Talbot effect—a time-frequency counterpart of the well-known near field diffraction effect. We provide experimental results and highlight the possible applications in quantum communication, quantum information processing, and time-frequency quantum state tomography.

中文翻译：

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多维单光子时间段叠加的高效检测


检测量子叠加的能力是量子力学基础和应用方面的核心。光的时频自由度使得能够以与光纤和集成平台兼容的多维方式编码和传输量子信息。然而，有效检测高维时间段叠加（更广泛的时频范式中的编码子集）的能力尚不可用。在这里，我们展示了可以使用单个时间分辨光子探测器来检测多维时间段叠加。我们的方法使用现成的组件，并基于时间塔尔伯特效应——众所周知的近场衍射效应的时频对应物。我们提供实验结果并强调其在量子通信、量子信息处理和时频量子态断层扫描中的可能应用。