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arXiv · 2406.04909

Orchestrating time and color: a programmable source of high-dimensional entanglement

Laura Serino·Werner Ridder·Abhinandan Bhattacharjee·Jano Gil-Lopez·Benjamin Brecht·Christine Silberhorn
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Abstract

High-dimensional encodings based on temporal modes (TMs) of photonic quantum states provide the foundations for a highly versatile and efficient quantum information science (QIS) framework. Here, we demonstrate a crucial building block for any QIS applications based on TMs: a programmable source of maximally entangled high-dimensional TM states. Our source is based on a parametric down-conversion process driven by a spectrally shaped pump pulse, which facilitates the generation of maximally entangled TM states with a well-defined dimensionality that can be chosen programmatically. We characterize the effective dimensionality of the generated states via measurements of second-order correlation functions and joint spectral intensities, demonstrating the generation of bi-photon TM states with a controlled dimensionality in up to 20 dimensions.

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Laura Serino, Werner Ridder, Abhinandan Bhattacharjee, Jano Gil-Lopez, Benjamin Brecht, Christine Silberhorn. 2024-06-07. Orchestrating time and color: a programmable source of high-dimensional entanglement. https://doi.org/10.1364/opticaq.532334

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