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arXiv · 2407.01429

Generalized Quantum Repeater Graph States

Bikun Li·Kenneth Goodenough·Filip Rozpędek·Liang Jiang
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Abstract

All-photonic quantum repeaters are essential for establishing long-range quantum entanglement. Within repeater nodes, reliably performing entanglement swapping is a key component of scalable quantum communication. To tackle the challenge of probabilistic Bell state measurement in linear optics, which often leads to information loss, various approaches have been proposed to ensure the loss tolerance of distributing a single ebit. We have generalized previous work regarding repeater graph states with elaborate connectivity, enabling the efficient establishment of exploitable ebits at a finite rate with high probability. We demonstrate that our new scheme significantly outperforms the previous work with much flexibility and discuss the generation overhead of such resource states. These findings offer new insights into the scalability and reliability of loss-tolerant quantum networks.

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Bikun Li, Kenneth Goodenough, Filip Rozpędek, Liang Jiang. 2024-07-01. Generalized Quantum Repeater Graph States. https://doi.org/10.1103/physrevlett.134.190801

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