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arXiv · 1912.09259

Indistinguishable photons from a trapped-ion quantum network node

M. Meraner·A. Mazloom·V. Krutyanskiy·V. Krcmarsky·J. Schupp·D. Fioretto·P. Sekatski·T. E. Northup·N. Sangouard·B. P. Lanyon
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Abstract

Trapped atomic ions embedded in optical cavities are a promising platform to enable long-distance quantum networks and their most far-reaching applications. Here we achieve and analyze photon indistinguishability in a telecom-converted ion-cavity system. First, two-photon interference of cavity photons at their ion-resonant wavelength is observed and found to reach the limits set by spontaneous emission. Second, this limit is shown to be preserved after a two-step frequency conversion replicating a distributed scenario, in which the cavity photons are converted to the telecom C band and then back to the original wavelength. The achieved interference visibility and photon efficiency would allow for the distribution and practical verification of entanglement between ion-qubit registers separated by several tens of kilometers.

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M. Meraner, A. Mazloom, V. Krutyanskiy, V. Krcmarsky, J. Schupp, D. Fioretto, P. Sekatski, T. E. Northup, N. Sangouard, B. P. Lanyon. 2019-12-19. Indistinguishable photons from a trapped-ion quantum network node. https://doi.org/10.1103/physreva.102.052614

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