“Sub-wavelength Photonic Semiconductor Nanostructures and their Applications”

Abstract:

Light-matter interactions at subwavelength scales provide unique optical characteristics interesting from both basic science and application perspectives. For example, sub-wavelength nanostructures can resonantly scatter or confine light in small volumes, controlled by their geometry and material properties. The spatial arrangement of the nanostructures offers yet another degree of freedom to manipulate their collective optical properties. Examples of such nanostructured materials/surfaces include photonic crystals and metasurfaces that have found several applications in integrated photonics, flat optics, optoelectronic devices, structural colors and nonlinear optics. Recently, good old high index dielectric Mie resonators have gained prominence due to the possibility of creating new types of optical states with strong light confinement, such as quasi bound-states in a continuum and anapoles.

This talk presents an overview of this fast developing field and the group’s research on semiconductor-based subwavelength structures focusing on their optical properties, fabrication technologies and applications. The highlighted application examples include our recent work on structural colors, broadband anti-reflection for solar cells, light extraction and color conversion in LEDs and optical anapoles.