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arXiv · 1803.09917

Electrically-activated spin-controlled orbital angular momentum multiplexer

Gianluca Ruffato·Etienne Brasselet·Michele Massari·Filippo Romanato
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Abstract

We present and test the integration of a static orbital angular momentum mode multiplexer with a dynamical geometric-phase optical element enabling on-demand spin-controlled angular momentum multiplexing. A diffractive optics multiplexer fabricated with 3D high-resolution electron beam lithography performs a conformal mapping for the conversion from linear to azimuthal phase gradients. The latter is functionalized by a dynamic spin-orbit add-on that consists of a self-engineered electrically-activated liquid crystal optical vortex generator having large clear-aperture and high-resolution. By combining several functionalities based on the optical angular momentum of light in a compact manner, the proposed hybrid device could find applications in next-generation high-dimensional mode switchers and routers based on orbital angular momentum.

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Gianluca Ruffato, Etienne Brasselet, Michele Massari, Filippo Romanato. 2018-03-27. Electrically-activated spin-controlled orbital angular momentum multiplexer. https://doi.org/10.1063/1.5030844

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