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arXiv · 2005.07219

Local versus Global Two-Photon Interference in Quantum Networks

Thomas Nitsche·Syamsundar De·Sonja Barkhofen·Evan Meyer-Scott·Johannes Tiedau·Jan Sperling·Aurél Gábris·Igor Jex·Christine Silberhorn
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Abstract

We devise an approach to characterizing the intricate interplay between classical and quantum interference of two-photon states in a network, which comprises multiple time-bin modes. By controlling the phases of delocalized single photons, we manipulate the global mode structure, resulting in distinct two-photon interference phenomena for time-bin resolved (local) and time-bucket (global) coincidence detection. This coherent control over the photons' mode structure allows for synthesizing two-photon interference patterns, where local measurements yield standard Hong-Ou-Mandel dips while the global two-photon visibility is governed by the overlap of the delocalized single-photon states. Thus, our experiment introduces a method for engineering distributed quantum interferences in networks.

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Thomas Nitsche, Syamsundar De, Sonja Barkhofen, Evan Meyer-Scott, Johannes Tiedau, Jan Sperling, Aurél Gábris, Igor Jex, Christine Silberhorn. 2020-05-14. Local versus Global Two-Photon Interference in Quantum Networks. https://doi.org/10.1103/physrevlett.125.213604

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