Tunable Omnidirectional Resonance in Metal-Insulator-Metal Structures

In this paper, we present a new technique to achieve tunable omnidirectional resonance in planar metallic micro-cavity structures. It is demonstrated numerically with realistic material parameters that by changing the portion of different dielectric layers of sub-wavelength thickness in metal-dielectric-metal structure, the omnidirectional resonance can be tuned to an arbitrary frequency in the optical range. We also demonstrate that the same technique can be also used to realize tunable highpass filter in optical frequency range