Photonic band gaps of three-dimensional face-centered cubic lattices

Using the photonic analogue of the Korringa-Kohn-Rostocker (KKR) method, the spectrum of electromagnetic waves in a three-dimensional fcc lattice of homogeneous dielectric spheres with various dielectric contrast is analyzed. We confirm the main features of the spectrum obtained by the plane wave method, namely that for a sufficiently high dielectric contrast a full gap opens in the spectrum between the eights and ninth bands if the dielectric constant εs of spheres is lower than the dielectric constant εb of the background medium. If εs > εb, no gap is found in the spectrum. The lowest dielectric contrast εb/εs for which a full gap opens in the spectrum is around 8.13. The maximal value of the relative band-gap width approaches 14% in the close-packed case and decreases monotonically as the filling fraction decreases. PACS numbers: 41.10 Hv, 71.25Cx, 84.90.+a ∗e-mail address : [email protected] †e-mail address : [email protected]