Tensor-driven geometric phase in nonlinear AlGaAs metasurfaces

TL;DR

This paper demonstrates how tensor-driven geometric phase in nonlinear AlGaAs metasurfaces enables efficient nonlinear beam steering and structured-light generation, advancing nanoscale optical wavefront control.

Contribution

It introduces a novel approach using tensor-driven geometric phase in nonlinear AlGaAs metasurfaces for beam steering and structured-light generation.

Findings

Successful fabrication of AlGaAs metasurfaces with geometric phase control

Demonstration of nonlinear beam steering capabilities

Generation of structured light fields at the harmonic frequency

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.