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arXiv · 2204.13081

Diffraction of an Off-axis Vector-Beam by a Tilted Aperture

Ghanasyam Remesh·Athira B S·Shyamal Gucchait·Ayan Banerjee·Nirmalya Ghosh·Subhasish Dutta Gupta
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Abstract

Manifestations of orbital angular momentum induced effects in the diffraction of a radially polarized vector beam by an off-axis tilted aperture are studied both experimentally and theoretically. Experiments were carried out to extract the degree of circular polarization, which was shown to be proportional to the on-axis component of the spin angular momentum density. We report a clear separation of the regions of dominance of the right and left circular polarizations associated with positive and negative topological charges respectively, which is reminiscent of the standard vortex-induced transverse shift, albeit in the diffraction scenario. The experimental results are supported by model simulations and the agreement is quite satisfactory. The results are useful to appreciate the orbit-orbit related effects due to unavoidable misalignment problems (especially for vortex beams).

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Ghanasyam Remesh, Athira B S, Shyamal Gucchait, Ayan Banerjee, Nirmalya Ghosh, Subhasish Dutta Gupta. 2022-04-27. Diffraction of an Off-axis Vector-Beam by a Tilted Aperture. https://doi.org/10.1088/2040-8986%2Fac8aac

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