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arXiv · 2312.14805

Quantum repeater node with free-space coupled trapped ions

Max Bergerhoff·Omar Elshehy·Stephan Kucera·Matthias Kreis·Jürgen Eschner
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Abstract

The quantum repeater cell is a basic building block for a quantum network, as it allows to overcome the distance limitations due to unavoidable fiber loss in direct transmission. We demonstrate the implementation of a quantum repeater cell, based on two free-space coupled $^{40}$Ca$^+$ ions in the same trap that act as quantum memories. We demonstrate the asynchronous generation of atom-photon and photon-photon entanglement by controlled emission of single photons from the individually addressed ions and entanglement swapping. We discuss the fidelity as well as the scaling of the generated rate.

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Max Bergerhoff, Omar Elshehy, Stephan Kucera, Matthias Kreis, Jürgen Eschner. 2023-12-22. Quantum repeater node with free-space coupled trapped ions. https://doi.org/10.1103/physreva.110.032603

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