LARGE OMNIDIRECTIONAL BAND-GAPS IN METALLODIELECTRIC PHOTONIC CRYSTALS

Using a finite-difference time-domain method, we study the band-struct ure and transmission properties of three-dimensional metallodielectric photonic crystals. The metallodielectric crystals are modeled as perf ect electrical conducting objects embedded in dielectric media. We inv estigate two different lattice geometries: the face-centered-cubic (fe e) lattice and the diamond lattice. Partial gaps are predicted in the fee lattice, in excellent agreement with recent experiments. Complete gaps are found in a diamond lattice of isolated metal spheres. The gap s appear between the second and third bands and their sizes can be lar ger than 60% when the radius of the spheres exceeds 21% of the cubic u nit cell size. A possible fabrication scheme for this structure is pro posed and transmission calculations are performed.