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arXiv · 2601.18246

Tensor-driven geometric phase in nonlinear AlGaAs metasurfaces

Giorgio Guercio·Andrea Gerini·Kristina Frizyuk·Costantino De Angelis·Martina Morassi·Aristide Lemaître·Luca Carletti·Giuseppe Leo
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Abstract

Dielectric metasurfaces provide a unique platform for efficient harmonic generation and optical wavefront manipulation at the nanoscale. While several approaches are available for performing wavefront shaping, the one exploiting geometric phase streamlines significantly the design and fabrication process. It has been recently shown that, in III-V semiconductor alloys, the rotation of the crystal axes affects the phase and amplitude of second-harmonic generation (SHG) induced by circularly polarized light [1]. Based on this notion, we fabricated and characterized two aluminum gallium arsenide metasurfaces displaying the versatility of the geometric phase design approach through nonlinear beam steering and structured-light generation on the harmonic field.

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Giorgio Guercio, Andrea Gerini, Kristina Frizyuk, Costantino De Angelis, Martina Morassi, Aristide Lemaître, Luca Carletti, Giuseppe Leo. 2026-01-26. Tensor-driven geometric phase in nonlinear AlGaAs metasurfaces. https://doi.org/10.1021/acsphotonics.6c00299

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