Three-dimensional metallodielectric photonic crystals incorporating flat metal elements

A three-dimensional metallodielectric photonic crystal (MDPC) that utilizes planar metal scattering elements in a dielectric medium has been studied in the microwave regime, both experimentally and theoretically. The metal elements are circular copper patches defined on thin dielectric sheets, which are alternately stacked with thicker polyethylene sheets to form a (111)-oriented face-centered-cubic lattice. A photonic stop band has been measured from this 'flat-atom' MDPC at 8.2 GHz with a rejection level of 18 dB per lattice period and a width of 50% of the center frequency. The photonic stop band persists over a broad range of angles. Finite-Difference Time-Domain calculations show excellent agreement with measured stop band characteristics, including a similar angular dependence and insensitivity to interplane registration. Variation of the stop-band characteristics with thickness of the dielectric layers has also been explored experimentally. Flat-atom MDPC results are compared with measurements made on 'spherical-atom' MDPC structures.