Switching Plasmon Resonances by Polarization of the Incident Light in Metamolecules

We numerically demonstrate the modulation of plasmon resonances in a metamolecule composed of metal bars and L-shaped nanoparticles by using the finite difference time domain method. Due to the dependence of electromagnetic coupling on polarization of the incident light, we show that the superradiant and subradiant states can be switched from ON and OFF resonantly. These two resonances are continuously adjustable as the polarization angle of incident wave changes. This feature reveals a possibility of dynamically switching the coupled plasmon resonances of an artificial microstructure and to construct functional metamaterials, which is helpful for nanophotonic devices such as filters and optical switches.