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arXiv · 2309.05234

High-dimensional time-frequency entanglement in a singly-filtered biphoton frequency comb

Xiang Cheng·Kai-Chi Chang·Murat Can Sarihan·Andrew Mueller·Maria Spiropulu·Matthew D. Shaw·Boris Korzh·Andrei Faraon·Franco N. C. Wong·Jeffrey H. Shapiro·Chee Wei Wong
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Abstract

High-dimensional quantum entanglement is a cornerstone for advanced technology enabling large-scale noise-tolerant quantum systems, fault-tolerant quantum computing, and distributed quantum networks. The recently developed biphoton frequency comb (BFC) provides a powerful platform for high-dimensional quantum information processing in its spectral and temporal quantum modes. Here we propose and generate a singly-filtered high-dimensional BFC via spontaneous parametric down-conversion by spectrally shaping only the signal photons with a Fabry-Perot cavity. High-dimensional energy-time entanglement is verified through Franson-interference recurrences and temporal correlation with low-jitter detectors. Frequency- and temporal- entanglement of our singly-filtered BFC is then quantified by Schmidt mode decomposition. Subsequently, we distribute the high-dimensional singly-filtered BFC state over a 10 km fiber link with a post-distribution time-bin dimension lower bounded to be at least 168. Our demonstrations of high-dimensional entanglement and entanglement distribution show the capability of the singly-filtered quantum frequency comb for high-efficiency quantum information processing and high-capacity quantum networks.

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Xiang Cheng, Kai-Chi Chang, Murat Can Sarihan, Andrew Mueller, Maria Spiropulu, Matthew D. Shaw, Boris Korzh, Andrei Faraon, Franco N. C. Wong, Jeffrey H. Shapiro, Chee Wei Wong. 2023-09-12. High-dimensional time-frequency entanglement in a singly-filtered biphoton frequency comb. https://arxiv.org/abs/2309.05234

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