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arXiv · 2110.07183

High-Dimensional Entanglement of Photonic Angular Qudits

Graciana Puentes·Giacomo Sorelli
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Abstract

We propose a method for generation of entangled photonic states in high dimensions, the so-called qudits, by exploiting quantum correlations of Orbital Angular Momentum (OAM) entangled photons, produced via Spontaneous Parametric Down Conversion. Diffraction masks containing $N$ angular slits placed in the path of twin photons define a qudit space of dimension $N^2$, spanned by the alternative pathways of OAM-entangled photons. We quantify the high-dimensional entanglement of path-entangled photons by the Concurrence, using an analytic expression valid for pure states. We report numerical results for the Concurrence as a function of the angular aperture size for the case of high-dimensional OAM entanglement and for the case of high-dimensional path entanglement, produced by $N \times M$ angular slits. Our results provide additional means for preparation and characterization of entangled quantum states in high-dimensions, a fundamental resource for quantum simulation and quantum information protocols.

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Graciana Puentes, Giacomo Sorelli. 2021-10-14. High-Dimensional Entanglement of Photonic Angular Qudits. https://doi.org/10.3389/fphy.2022.868522

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