Transforming the concept of band topology fostered in electron systems to electromagnetic waves opens a completely new direction for harnessing propagation of light. It is observed that electromagnetic modes in honeycomb photonic crystals exhibit Dirac-type frequency dispersions, which are accompanied by emergent spin degree of freedom, and that deforming the honeycomb structure in a designed way gives birth to a photonic analogue of quantum spin Hall effect. In this talk I will first show that the main physics can be captured phenomenologically by the k∙p theory, and discuss that the photonic topology can be characterized in terms of the Wilson loops based on the C_2 T symmetry. Then I will introduce examples to demonstrate how the recipe can be exploited for harnessing light and deriving advanced optic properties.
Monday,12,01,2026
2:00 pm
Room 522, 5/F, Chong Yuet Ming Physics Building, HKU
HK Institute of Quantum Science & Technology, Room525, Chong Yuet Ming Physics Building, The University of Hong Kong Phone: 3917 1108