Mid-infrared Nonlinear Polaritonic Metasurfaces

Abstract

In the realm of linear optics, metasurfaces have enabled the development of intriguing applications based on flat optical components. However, the exploration of nonlinear responses in metasurfaces has demonstrated significant potential for diverse applications such as nonlinear holography, spectroscopy, and the realization of novel nonlinear light sources. Nonlinear metasurfaces offer the advantage of relaxed phase-matching requirements, which simplifies the design of nonlinear optical systems. Nevertheless, the practical utilization of nonlinear metasurfaces with an accessible optical pump source necessitates the achievement of substantial nonlinear responses. Intersubband transitions in semiconductor heterostructures offer a way to achieve large and designable nonlinearities with dynamic modulation of subband energy through the Stark effect. One promising approach for incorporating these nonlinearities into free space optics is nonlinear polaritonic metasurface, which derive resonant coupling between intersubband nonlinearities and optical modes in nanocavities. In this dissertation, by combining a quantum-engineered semiconductor heterostructure with nanocavities I exploit nonlinear polaritonic metasurfaces for efficient frequency mixing at low pumping intensities, with the ability to electrically tune phase, amplitude, and spectral peak of it. This work will provide a promising route for efficient flat nonlinear optical elements which have giant and electrically tunable nonlinearity.