Physical Review A

Model for optimizing the visibility of time-bin entanglement

Zhen-Qiu Zhong, Xiao-Hai Zhan, Shuang Wang, Zhen−Qiang Yin, De‐Yong He, Wei Chen, Guang‐Can Guo, Zheng‐Fu Han

Published Oct 15, 2024• 6 citations

Abstract

Time-bin entanglement is a critical resource in quantum information science owing to its exceptional robustness over long-distance channels. Achieving high quantum interference visibility is indispensable for fundamental research and practical applications. To date, a model that can accurately describe time-bin entanglement-based two-photon interference remains to be established. In this work, we analyze the underlying mechanisms for this type of interference and develop an effective model for experimentally optimizing the quantum interference visibility. We use this model to analyze the factors contributing to the decline in interference visibility and offer strategies to address these issues, and we also demonstrate its effectiveness through experiments. Our model can serve as a tool for time-bin entanglement-based systems, aiding in system design, the evaluation of expected outcomes, and the optimization of experimental setups.

DOI: 10.1103/physreva.110.042414

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