Circular split-ring core resonators used in nanoscale metal-insulator-metal band-stop filters

摘要

A novel structure with a circular split-ring core is presented to improve the surface plasmon polaritons' (SPPs) transmission characteristic through a nanoscale band-stop filter of the metal-insulator-metal (MIM) structure. With a metal wall created at the center of the disk resonator, novel structures and the transmission characteristics are studied in several different situations. Some absorption peaks appear in the spectrum, and will shift while changing the dimension of the gap and the refractive index of the insulator. The magnetic field distributions with SPPs propagating through the filter are plotted. Meanwhile, a method is adopted to enhance the absorption peak values of the transmittance. This is important for potential applications in optical integrated circuits and other nanoscale devices.