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arXiv · 2301.06091

Full Bell-basis measurement of an atom-photon 2-qubit state and its application for quantum networks

Elena Arenskötter·Stephan Kucera·Omar Elshehy·Max Bergerhoff·Matthias Kreis·Léandre Brunel·Jürgen Eschner
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Abstract

The efficiency of a Bell-state measurement on photon pairs is bound to 50\,\% due to the number of Bell states that can be distinguished using linear optics. Here we present the implementation of a protocol that allows us to distinguish all four Bell states by the use of a single-ion quantum memory and heralded absorption as state-selective measurement. The protocol is implemented in two steps. First we demonstrate the state-preserving mapping of a photonic qubit onto the quantum memory, verified by the preservation of entanglement in the process. Then we demonstrate the full Bell state projection between a memory qubit and an incoming photonic qubit, by applying it for atom-to-photon quantum state teleportation.

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Elena Arenskötter, Stephan Kucera, Omar Elshehy, Max Bergerhoff, Matthias Kreis, Léandre Brunel, Jürgen Eschner. 2023-01-15. Full Bell-basis measurement of an atom-photon 2-qubit state and its application for quantum networks. https://doi.org/10.1103/physrevresearch.6.023061

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