Generation of even and odd high harmonics in resonant metasurfaces using single and multiple ultra-intense laser pulses.

Shcherbakov, Maxim R; Zhang, Haizhong; Tripepi, Michael; Sartorello, Giovanni; Talisa, Noah; AlShafey, Abdallah; Fan, Zhiyuan; Twardowski, Justin et al. · Nat Commun · 2021

basic_science · Level V

Where this comes from

Abstract

High harmonic generation (HHG) opens a window on the fundamental science of strong-field light-mater interaction and serves as a key building block for attosecond optics and metrology. Resonantly enhanced HHG from hot spots in nanostructures is an attractive route to overcoming the well-known limitations of gases and bulk solids. Here, we demonstrate a nanoscale platform for highly efficient HHG driven by intense mid-infrared laser pulses: an ultra-thin resonant gallium phosphide (GaP) metasurface. The wide bandgap and the lack of inversion symmetry of the GaP crystal enable the generation of even and odd harmonics covering a wide range of photon energies between 1.3 and 3 eV with minimal reabsorption. The resonantly enhanced conversion efficiency facilitates single-shot measurements that avoid material damage and pave the way to study the controllable transition between perturbative and non-perturbative regimes of light-matter interactions at the nanoscale.