Controlling light with nonlinear quasicrystal metasurfaces

TL;DR

This paper introduces nonlinear quasicrystal metasurfaces that manipulate light through geometric phase control, revealing how local and global symmetries influence nonlinear optical responses.

Contribution

It designs and fabricates nonlinear optical quasicrystal metasurfaces based on Penrose and hexagonal tilings, linking local meta-atom symmetry with global quasicrystal structure.

Findings

Second harmonic generation depends on tiling schemes and local symmetry.

Demonstrates control of nonlinear optical responses via quasicrystal design.

Provides a new approach for designing nonlinear metasurfaces with tailored functionalities.

Abstract

Metasurface, a kind of two-dimensional structured medium, represents a novel platform to manipulate the propagation of light at subwavelength scale. In linear optical regime, many interesting topics such as planar metalens, metasurface optical holography and so on have been widely investigated. Recently, metasurfaces go into nonlinear optical regime. While it is recognized that the local symmetry of the meta-atoms plays vital roles, its relationship with global symmetry of the nonlinear metasurfaces remains elusive. According to the Penrose tiling and the newly proposed hexagonal quasicrystalline tiling, here we designed and fabricated the nonlinear optical quasicrystal metasurfaces based on the geometric phase controlled plasmonic meta-atoms with local rotational symmetry. The second harmonic waves will be determined by both the tiling schemes of quasicrystal metasurfaces and the local symmetry of meta-atoms they consist of. The proposed concept opens new routes for designing nonlinear metasurface crystals with desired optical functionalities.