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arXiv · 2404.16106

A robust approach for time-bin encoded photonic quantum information protocols

Simon J. U. White·Emanuele Polino·Farzad Ghafari·Dominick J. Joch·Luis Villegas-Aguilar·Lynden K. Shalm·Varun B. Verma·Marcus Huber·Nora Tischler
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Abstract

Quantum states encoded in the time-bin degree of freedom of photons represent a fundamental resource for quantum information protocols. Traditional methods for generating and measuring time-bin encoded quantum states face severe challenges due to optical instabilities, complex setups, and timing resolution requirements. To circumvent these issues, we leverage an approach based on Hong-Ou-Mandel interference and we propose and demonstrate a robust and scalable protocol to generate and measure arbitrary high-dimensional time-bin quantum states. We experimentally implement the protocol in a photonic setup reaching high-fidelity quantum state tomographies of two and three-dimensional quantum states encoded in time-bins with short temporal separation. We also certify intrasystem polarization-time entanglement of single photons through a nonclassicality test. The demonstrated approach enables access to high-dimensional states and tasks that are practically inaccessible with standard schemes, thereby advancing fundamental quantum information science and opening applications in quantum communication.

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Simon J. U. White, Emanuele Polino, Farzad Ghafari, Dominick J. Joch, Luis Villegas-Aguilar, Lynden K. Shalm, Varun B. Verma, Marcus Huber, Nora Tischler. 2024-04-24. A robust approach for time-bin encoded photonic quantum information protocols. https://doi.org/10.1103/physrevlett.134.180802

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