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arXiv · 2410.03606

Programmable time-frequency mode-sorting of single photons with a multi-output quantum pulse gate

Laura Serino·Christof Eigner·Benjamin Brecht·Christine Silberhorn
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Abstract

We demonstrate a high-dimensional mode-sorter for single photons based on a multi-output quantum pulse gate, which we can program to switch between different temporal-mode encodings including pulse modes, frequency bins, time bins, and their superpositions. This device can facilitate practical realizations of quantum information applications such as high-dimensional quantum key distribution, and thus enables secure communication with enhanced information capacity. We characterize the mode-sorter through a detector tomography in 3 and 5 dimensions and find a fidelity up to $0.958\pm 0.030$ at the single-photon level.

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Laura Serino, Christof Eigner, Benjamin Brecht, Christine Silberhorn. 2024-10-04. Programmable time-frequency mode-sorting of single photons with a multi-output quantum pulse gate. https://doi.org/10.1364/oe.544206

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