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arXiv · 2411.19277

Self-guided tomography of time-frequency qudits

Laura Serino·Markus Rambach·Benjamin Brecht·Jacquiline Romero·Christine Silberhorn
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Abstract

High-dimensional time-frequency encodings have the potential to significantly advance quantum information science; however, practical applications require precise knowledge of the encoded quantum states, which becomes increasingly challenging for larger Hilbert spaces. Self-guided tomography (SGT) has emerged as a practical and scalable technique for this purpose in the spatial domain. Here, we apply SGT to estimate time-frequency states using a multi-output quantum pulse gate. We achieve fidelities of more than 99\% for 3- and 5-dimensional states without the need for calibration or post-processing. We demonstrate the robustness of SGT against statistical and environmental noise, highlighting its efficacy in the photon-starved regime typical of quantum information applications.

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Laura Serino, Markus Rambach, Benjamin Brecht, Jacquiline Romero, Christine Silberhorn. 2024-11-28. Self-guided tomography of time-frequency qudits. https://doi.org/10.1088/2058-9565%2Fadb0ea

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