Photonic band gaps and flat band edges in periodically textured metallic microcavities

The dispersion of optical modes in metallic microcavities is shown to be dr amatically altered when wavelength-scale periodic texture is added to one o f the cavity mirrors. We demonstrate that Bragg scattering of the cavity mo des by such microstructure produces near-flat bands that remain significant ly flat well away from the first Brillouin zone boundary. The electric fiel ds associated with these modes are studied and are found to have field maxi ma that are enhanced over those pertaining to planar microcavities. The imp act of this band structure upon emissive devices, especially in terms of th e clear insensitivity to viewing angle, is discussed. (C) 2000 American Ins titute of Physics. [S0003-6951(00)02927-2].