Optical and structural properties of dielectric metasurfaces under extreme illumination: from high-harmonics generation to nano-shaping

Theoretical and experimental results demonstrating reversible and irreversible regimes of laser-metasurface interactions will be presented. We will show how different types of semiconductor metasurfaces enable the generation of high harmonics, including even ones. We will also demonstrate laser-assisted nanostructuring of pre-fabricated metasurfaces that produce high-aspect features with strongly sub-wavelength (less than wavelength/50) feature sizes.