High-aspect-ratio silica meta-optics for high-intensity structured light

TL;DR

This paper introduces high-aspect-ratio silica meta-optics that enable robust manipulation of structured light at high intensities, surpassing damage thresholds of conventional metasurfaces, with applications in extreme laser-matter interactions.

Contribution

The authors develop and demonstrate silica-based metasurfaces with high aspect ratios, providing durable phase and polarization control for high-intensity structured light.

Findings

Fabrication of nanopillars with aspect ratios up to 14.

Generation of vortex beams at high intensities.

Effective polarization manipulation at long-visible wavelengths.

Abstract

Structured light and high-intensity ultrafast lasers are two rapidly advancing frontiers in photonics, yet their intersection remains largely unexplored. While ultrafast lasers continue to push the boundaries of peak intensities, structured light has enabled unprecedented control over light's spatial, temporal, and polarization properties. However, the lack of robust optical devices capable of bridging structured light with the high-intensity domain has constrained progress in combining these directions. Here, we demonstrate high-aspect-ratio silica meta-optics, which close this gap by combining silica's extraordinary damage resistance with the advanced phase and polarization control offered by metasurfaces. By leveraging anisotropic etching techniques, we fabricate nanopillars exceeding 3 $\mu$m in height with aspect ratios up to 14, enabling precise manipulation of complex light fields at intensities far beyond the thresholds of conventional metasurfaces. We showcase their functionality in generating vortex beams and achieving polarization manipulation with large phase retardance at challenging long-visible wavelengths. High-aspect-ratio silica meta-optics unlock structured laser-matter interactions in extreme regimes, that will surpass plasma ionization thresholds and enable applications such as relativistic particle acceleration and high-harmonic generation with structured beams, for both tabletop ultrafast systems and large-scale laser facilities.