Photonic band structure: The face-centered-cubic case employing nonspherical atoms

We introduce a practical, new, face-centered-cubic dielectric structure which simultaneously solves two of the outstanding problems in photonic band structure. In this new ‘‘photonic crystal’’ the atoms are nonspherical, lifting the degeneracy at the W point of the Brillouin zone, and permitting a full photonic band gap rather than a pseudogap. Furthermore, this fully three-dimensional fcc structure lends itself readily to microfabrication on the scale of optical wavelengths. It is created by simply drilling three sets of holes 35.26° off vertical into the top surface of a solid slab or wafer, as can be done, for example, by chemical-beam-assisted ion etching.