Abstract
Polaritons provide a versatile platform for manipulating light–matter interaction at the nanoscale due to their strong field confinement, large in-plane momentum, and sensitivity to material resonances. In graphene-based systems, an external magnetic field can quantize the electronic spectrum into Landau levels, giving rise to a tunable optical Hall response and magneto-optical polaritonic behavior. When such a magnetically tunable two-dimensional material is coupled to engineered photonic structures, including multilayer van der Waals heterostructures and photonic crystals, new opportunities emerge for controlling hybrid polariton dispersion, propagation, and mode confinement.
This seminar presents preliminary theoretical and numerical studies of graphene-coupled photonic systems. The optical Hall response of graphene is first calculated from Landau-level transitions, providing the frequency-dependent longitudinal and Hall conductivities. Transfer matrix theory is then used to model polariton dispersion in multilayer heterostructures, where guided polariton branches are identified from the imaginary part of the p-polarized reflection coefficient. Photonic-crystal platforms, including Wu–Hu, honeycomb, and square-lattice structures, are further considered as possible routes for coupling graphene to engineered photonic modes. Based on these studies, several future directions are proposed, including the hybridization between graphene topological edge states and photon modes, flat-band-enhanced graphene–polariton coupling, and the possible role of quantum geometry in flat-band polaritonic systems.
Anyone interested is welcome to attend.