Size-Independent Prism Resonator Partially Filled With DNG Metamaterial

A cavity resonator in the shape of a prism with a square base and walls that are either perfect electric or perfect magnetic conductors is considered. The resonator consists of two identical prisms with triangular bases, filled respectively with a double-positive material and a double-negative metamaterial, the two materials having opposite refractive indexes and the same intrinsic impedance. It is shown that electromagnetic fields whose electric or magnetic field is parallel to the height of the prism may exist for any dimensions of the cavity.