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arXiv · 2404.04958

Demonstration of quantum network protocols over a 14-km urban fiber link

Stephan Kucera·Christian Haen·Elena Arenskötter·Tobias Bauer·Jonas Meiers·Marlon Schäfer·Ross Boland·Milad Yahyapour·Maurice Lessing·Ronald Holzwarth·Christoph Becher·Jürgen Eschner
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Abstract

We report on the implementation of quantum entanglement distribution and quantum state teleportation over a 14.4-km urban dark-fiber link, which is partially underground, partially overhead, and patched in several stations. We characterize the link for its use as a quantum channel and realize its active polarization stabilization. Using a type-II cavity-enhanced SPDC photon pair source, a $^{40}$Ca$^{+}$ single-ion quantum memory, and quantum frequency conversion to the telecom C-band, we demonstrate photon-photon entanglement, ion-photon entanglement, and teleportation of a qubit state from the ion onto a remote telecom photon, all realized over the urban fiber link.

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Stephan Kucera, Christian Haen, Elena Arenskötter, Tobias Bauer, Jonas Meiers, Marlon Schäfer, Ross Boland, Milad Yahyapour, Maurice Lessing, Ronald Holzwarth, Christoph Becher, Jürgen Eschner. 2024-04-07. Demonstration of quantum network protocols over a 14-km urban fiber link. https://arxiv.org/abs/2404.04958

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