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arXiv · 1807.06342

Direct phase mapping of broadband Laguerre-Gaussian metasurfaces

Alexander Faßbender·Jiří Babocký·Petr Dvořák·Vlastimil Křápek·Stefan Linden
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Abstract

We report on the fabrication of metasurface phase plates consisting of gold nanoantenna arrays that generate Laguerre-Gaussian modes from a circularly polarized Gaussian input beam. The corresponding helical phase profiles with radial discontinuities are encoded in the metasurfaces by the orientation of the nanoantennas. A common-path interferometer is used to determine the orbital angular momentum of the generated beams. Additionally, we employ digital holography to record detailed phase profiles of the Laguerre-Gaussian modes. Experiments with different laser sources demonstrate the broadband operation of the metasurfaces.

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Alexander Faßbender, Jiří Babocký, Petr Dvořák, Vlastimil Křápek, Stefan Linden. 2018-07-17. Direct phase mapping of broadband Laguerre-Gaussian metasurfaces. https://arxiv.org/abs/1807.06342

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