Recent research activities on nanophotonics are mainly focused on the development of metasurface photonic devices. In this talk, Prof. Song will discuss main principles of phase modulation in metasurfaces: resonance phase-delay and geometric phase-delay, and will introduce a novel non-Hermitian topology (NH-TP) concept as a new way of phase control in nanophotonics. The NH-TP photonic platforms may take advantage of stable topological phenomena, strong unidirectionality, and broadband time-asymmetry in photon propagation.

 The need for nanotechnology is increasing to cope with the future megatrends of energy, environment, climate change and aging, and technological advancements such as big data and artificial intelligence. Industrial environments demand lighter and smaller products, and also require the implementation of a variety of complex functions and rapid response. Nano materials meet the demands of the industry by controlling the change in physical, chemical, and biological properties due to nano sizes as well as physical properties such as size, surface area, and pores. As a result, nanotechnology is expected to overcome the limitations of the existing manufacturing industry and contribute to the creation of new industries.