Plasmonic analog of electromagnetic-induced transparency of asymmetrical slots waveguide

摘要

Electromagnetically induced transparency (EIT) has been proposed numerically in the plasmonic waveguides composed of unsymmetrical slots shaped metal-insulator-metal (MIM) structures. By the transmission line theory and Fabry-Perot model, the formation and evolution mechanisms of Plasmon induced transparency are exactly analyzed. The analysis shows that the peak of EIT-like transmission can be changed easily according to certain rules by adjusting the geometrical parameters of the slot structures, including the coupling distances and slot depths. We can find a new method to design nanoscale optical switch, devices in optical storage and optical computing. It is found that the slow light effects are emerged in the unsymmetrical slot structures. A small group velocity(c/80) can be achieved.