Trapped mode resonances in optical planar periodical structures with metal and dielectric elements

The problem of infra red light diffraction on a planar 2-D periodic metal-dielectric or dielectric structures with square periodic cell has been solved. The periodic cell includes either two complex-shaped asymmetric metal elements or two dielectric bars with different lengths. The existence of a high order trapped mode resonance was shown for metal-dielectric structure and its properties were studied. For the first time, the existence of a trapped mode resonance in a dielectric planar structure was shown. Such resonances demonstrate greater quality factor then usual plasmon-polariton resonances.