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arXiv · 1906.05172

Parameter regimes for surpassing the PLOB bound with error-corrected qudit repeaters

Daniel Miller·Timo Holz·Hermann Kampermann·Dagmar Bruß
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Abstract

A potential quantum internet would open up the possibility of realizing numerous new applications, including provably secure communication. Since losses of photons limit long-distance, direct quantum communication and widespread quantum networks, quantum repeaters are needed. The so-called PLOB-repeaterless bound [Pirandola et al., Nat. Commun. 8, 15043 (2017)] is a fundamental limit on the quantum capacity of direct quantum communication. Here, we analytically derive the quantum-repeater gain for error-corrected, one-way quantum repeaters based on higher-dimensional qudits for two different physical encodings: Fock and multimode qudits. We identify parameter regimes in which such quantum repeaters can surpass the PLOB-repeaterless bound and systematically analyze how typical parameters manifest themselves in the quantum-repeater gain. This benchmarking provides a guideline for the implementation of error-corrected qudit repeaters.

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Daniel Miller, Timo Holz, Hermann Kampermann, Dagmar Bruß. 2019-06-12. Parameter regimes for surpassing the PLOB bound with error-corrected qudit repeaters. https://doi.org/10.22331/q-2019-12-16-216

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