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arXiv · 1503.06709

Heralded Storage of a Photonic Quantum Bit in a Single Atom

Norbert Kalb·Andreas Reiserer·Stephan Ritter·Gerhard Rempe
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Abstract

Combining techniques of cavity quantum electrodynamics, quantum measurement, and quantum feedback, we have realized the heralded transfer of a polarization qubit from a photon onto a single atom with 39% efficiency and 86% fidelity. The reverse process, namely, qubit transfer from the atom onto a given photon, is demonstrated with 88% fidelity and an estimated efficiency of up to 69%. In contrast to previous work based on two-photon interference, our scheme is robust against photon arrival-time jitter and achieves much higher efficiencies. Thus, it constitutes a key step toward the implementation of a long-distance quantum network.

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Norbert Kalb, Andreas Reiserer, Stephan Ritter, Gerhard Rempe. 2015-03-23. Heralded Storage of a Photonic Quantum Bit in a Single Atom. https://doi.org/10.1103/physrevlett.114.220501

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