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arXiv · 2604.27739

OAM-mode sorting with a wavefront twister

Suman Karan·Swati Chaudhary·Harshwardhan Wanare·Anand Kumar Jha
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Abstract

We propose an OAM sorter based on a novel optical element that we refer to as a wavefront twister. It is a generalization of the conventional wavefront rotators such as the Dove prism. However, unlike a Dove prism, which simply rotates a wavefront, the rotation generated by a wavefront twister varies linearly with radial position, resulting in the twisting of the wavefront. We demonstrate that the wavefront twister, followed by a lens, maps each OAM mode to an annulus of distinct radius at the back focal plane of the lens with negligible inter-modal overlap and preserves the circular symmetry. Thus, the proposed wavefront twister offers a scalable scheme for high-dimensional OAM mode sorting, with important consequences for the practical realization of OAM-based applications.

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Suman Karan, Swati Chaudhary, Harshwardhan Wanare, Anand Kumar Jha. 2026-04-30. OAM-mode sorting with a wavefront twister. https://arxiv.org/abs/2604.27739

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