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arXiv · 2502.18588

Detection of Orbital Angular Momentum Modes via Spiral Phase Plate

Amin Hakimi·S. Faezeh Mousavi·Amir Nader Askarpour
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Abstract

Mode division multiplexing (MDM) systems leveraging spatial modes carrying orbital angular momentum (OAM) present a promising approach to enhance communication capacity in free-space and fiber-optic networks. Efficient detection of OAM modes is critical for their practical implementation. Spiral phase plates (SPPs) are low-cost optical elements with simple structures, capable of generating OAM waves with high conversion efficiency and precision. This makes the inverse-SPP a promising candidate for the detection of OAM modes. In this study, the performance of SPPs as OAM detectors is thoroughly analyzed. Key parameters, including efficiency, crosstalk, and signal-to-interference ratio, are examined through analytical and numerical methods. Results demonstrate that an inverse-SPP, combined with an optimized propagation length and aperture size, enables effective and precise OAM detection operation.

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Amin Hakimi, S. Faezeh Mousavi, Amir Nader Askarpour. 2025-02-25. Detection of Orbital Angular Momentum Modes via Spiral Phase Plate. https://arxiv.org/abs/2502.18588

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