We present results of photonic band-structure calculations for inverted photonic crystal structures. We consider a structure of air spheres in a dielectric background, arranged in an fcc lattice, with a cylindrical tunnel connecting each pair of neighboring spheres. We derive (semi)analytical expressions for the Fourier coefficients of the dielectric susceptibility, which are used as input in a standard plane-wave expansion method. We optimize the width of the photonic bandgap by applying a gradient search method and varying two geometrical parameters in the system: the ratios R/a and Rc/R, where a is the lattice constant, R is the sphere radius, and Rc is the cylinder radius. It follows from our calculations that the maximal gap width in this type of photonic-crystal structure with air spheres and cylinders in silicon is Δω/ω0=9.59%.
© 2000 Optical Society of America
(000.4430) General : Numerical approximation and analysis
(160.4670) Materials : Optical materials
(160.4760) Materials : Optical properties
(260.2030) Physical optics : Dispersion
(260.2110) Physical optics : Electromagnetic optics
Marcel Doosje, Bernhard J. Hoenders, and Jasper Knoester, "Photonic bandgap optimization in inverted fcc photonic crystals," J. Opt. Soc. Am. B 17, 600-606 (2000)