Nonlinear dielectric metasurfaces for frequency conversion (Conference Presentation)

Abstract

Dielectric metasurfaces have proven to be able to manipulate the wavefront of incoming waves with high transmission efficiency. The important next question is: Can they enable enhanced interaction with the light to transform its colour or to be able to control one light beam with another? Here we show how an ultra-thin surface of subwavelength thickens can enable enhanced light matter interaction for efficient frequency conversion and ultra-fast light modulation. In particular, we show how designer dielectric metasurfaces can enhance second and third harmonic generation resulting in complete nonlinear control of directionality and polarisation state of the harmonics. Furthermore, we demonstrate how such enhanced light matter interactions can lead to optical switching with unprecedented speed. Our results open novel applications in ultra-thin light sources, light switches and modulators, ultra-fast displays, and other nonlinear optical metadevices based on low loss subwavelength dielectric resonant nanoparticles.