Multispectral Plasmon Induced Transparency in a Defective Metasurface Plasmonic Nanostructure

The investigation of plasmon induced transparency (PIT) resonances is performed in a system based on defective and complete silver nanostrips. The response of metasurface systems to electromagnetic fields under normal incidence is endowed by unique features, including some exquisite spatial phenomena. These phenomena are embodied in confined light-matter hybrid modes where the defective silver nanostrip excites superradiant dipole and quadrupole modes, resulting in a PIT window. Moreover, multispectral PIT resonances are observed, which involves quadrupole mode as superradiant to excite the proximity nanostrip. It can reveal much about the defective metasurface structure, such as exact tuning of the gap distance between these two nanostrips, variation in defect parameters and modulating in electric polarization angles of excitation. Still, our research realizes multiple PIT resonances in one nanostructure, which may have interesting applications of plasmonic switching devices in highly integrated circuits.