Influence of Dielectric Constant of Background on Optical Properties of Metallodielectric Photonic Crystals

We theoretically study the effect of the dielectric background in two-dimensional metal-dielectric photonic crystals. We calculate the photonic band structure by means of the plane wave expansion method. Results show that the band structures shift toward lower frequencies and become flatter when the background dielectric constant increases. In addition, degeneracy can be broken and new gaps can be created in function of the dielectric background. We also found that the relative band gap width Deltaomega/omega_g grows with increasing background dielectric constant and widths as large as 42.3% and 13.8% for the second and third band gaps can be achieved for epsiv_b = 9.