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arXiv · 2301.05724

Distribution of genuine high-dimensional entanglement over 10.2 km of noisy metropolitan atmosphere

Lukas Bulla·Kristian Hjorth·Oskar Kohout·Jan Lang·Sebastian Ecker·Sebastian P. Neumann·Julius Bittermann·Robert Kindler·Marcus Huber·Martin Bohmann·Rupert Ursin·Matej Pivoluska
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Abstract

In a recent quantum key distribution experiment, high-dimensional protocols were used to show an improved noise resistance over a 10.2 km free-space channel. One of the unresolved questions in this context is whether the communicating parties actually shared genuine high-dimensional entanglement. In this letter we introduce an improved discretisation and entanglement certification scheme for high-dimensional time-bin setups and apply it to the data obtained during the experiment. Our analysis answers the aforementioned question affirmatively and thus the experiment constitutes the first transmission of genuine high-dimensional entanglement in a single degree of freedom over a long-range free-space channel.

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Lukas Bulla, Kristian Hjorth, Oskar Kohout, Jan Lang, Sebastian Ecker, Sebastian P. Neumann, Julius Bittermann, Robert Kindler, Marcus Huber, Martin Bohmann, Rupert Ursin, Matej Pivoluska. 2023-01-13. Distribution of genuine high-dimensional entanglement over 10.2 km of noisy metropolitan atmosphere. https://doi.org/10.1103/physreva.107.l050402

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