Light-matter interactions primarily depend on the material's atomic composition. Thus, naturally occuring materials have a very limited range of optical properties. However, structured materials that consist of mesoscopic meta-atoms can exhibit artificial optical properties not found in nature. For example, the maximum visible frequency refractive index that can be found in nature is around 5, but artificially designed metamaterials can have refractive indices larger than 10*. The meta-atoms are larger than actual atoms but smaller than the wavelength of light that it interacts with, to ensure light 'thinks' of the material as a homogeneous medium.
The design of metamaterials offer numerous parameters that can be tweaked to achieve various novel optical properties, with applications in displays, bio-imaging, photo-catalysis, optical communications, solar cells, etc.
* Chang, Taeyong, et al. Nature communications 7 (2016).
In this laboratory, we aim to discover and realize new optical properties not found in nature. There are 4 basic steps that are involved in this process: 1) theoretical work, 2) simulations, 3) fabrication, 4) property measurement. We are continuously working to achieve extraordinary phenomena such as extreme enhancement of optical properties, nonlinear optics, non-Maxwellian optics, etc.