Tight control of the flow of light through CMOS compatible metasurfaces

Light can be shaped in different ways and forms by means of interference. When scaling down to the micro and nanoscale, light waves in confined nanostructures can present intriguing interference effects that give rise to exotic optical effects. These subwavelength (sub-λ) optical resonator and scatterers are dramatically expanding the toolset of the optical sciences and photonics engineering. By offering the opportunity to control and shape light waves in nanoscale volumes, recent developments using both high-refractive-index dielectric and filter, directional color routers, hyperspectral imagers and biosensors, nonlinear elements and holograms with sub-λ thickness, by converting localized structured light fields at the nanoscale into propagating structured light waves in the far-field. These flat-optical systems are often referred to as metamaterials or metasurfaces and consist of carefully designed and arranged individual resonators or nanoantennas. Often millions working in unison to generate a variety of optical manipulations. The functionality is essentially determined by the light-matter interaction of its constituting building-blocks. These can resonantly or non-resonantly absorb and/or scatter light, change the propagating wave’s phase, induce non-linearity such as harmonic generation, etc. Interestingly, we can conveniently control and fine-tune these interactions and electromagnetic properties by changing geometrical parameters (shape and size) and material composition using precise nanofabrication. With this project, the PhD thesis will lay the foundations for next-generation optical devices that will be more performant, more compact, have more functionality, and find widespread applications in communication, optical computing, the life sciences, space exploration, and imaging.