Full band gap in fcc and bcc photonic band gaps structure: Non-spherical atom

The self-arrangement of colloidal crystal in the fee and bcc lattices is one way available to fabricate three dimensional periodic microstructures in the micron- and submicron-size regimes. The photonic band gaps (PBG) structure with its atom composed of two conjugate dielectric sphere in the uniform dielectric medium is revealed to possess full hand gap both in fee and bcc lattices. The photonic band structure is strongly dependent on the direction of the atom axis and there exist for both lattices some favorable directions of atom in opening a full hand gap. It is (1: 1, 1) for fee lattice and (2, 1, 0) for bcc lattice. The combination of such a PEG structure with the self-arrangement technique of colloidal crystal can provide a potential to fabricate the three dimensional photonic crystal with a full band gap in the optical regime.