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arXiv · 1905.00335

Scalable repeater architectures for multi-party states

V. V. Kuzmin·D. V. Vasilyev·N. Sangouard·W. Dür·C. A. Muschik
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Abstract

The vision to develop quantum networks entails multi-user applications, which require the generation of long-distance multi-party entangled states. The current rapid experimental progress in building prototype-networks calls for new design concepts to guide future developments. Here we describe an experimentally feasible scheme implementing a two-dimensional repeater network for robust distribution of three-party entangled states of GHZ type in the presence of excitation losses and detector dark counts --- the main sources of errors in real-world hardware. Our approach is based on atomic or solid state ensembles and employs built-in error filtering mechanisms peculiar to intrinsically two-dimensional networks. This allows us to overcome the performance limitation of conventional one-dimensional ensemble-based networks distributing multi-party entangled states and provides an efficient design for future experiments with a clear perspective in terms of scalability.

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V. V. Kuzmin, D. V. Vasilyev, N. Sangouard, W. Dür, C. A. Muschik. 2019-05-01. Scalable repeater architectures for multi-party states. https://doi.org/10.1038/s41534-019-0230-3

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