No abstract

We perform numerical analysis of ultralarge complete photonic bandgap (CPBG) of two-dimensional photonic crystals, which are square arrays of dielectric-shell rods, with dielectric veins and intersecting veins to link them. It is shown how a maximum CPBG, Δω = 0.222592(2πc/a), is obtained within the fabrication tolerance by tuning the structural parameters. In addition, the effects on CPBG arising from the metamaterial are also discussed.

In this paper we study the characteristics of subwavelength imaging of a photonic crystal (PhC) superlens under the influence of source displacement. For square-and triangular-lattice photonic crystal lenses, we investigate the influence of changing the lateral position of a single point source on the imaging uniformity and stability. We also study the effect of changing the geometrical center of a pair of sources on the resolution of the double-image. Both properties are found to be sensitive to the displacement, which implies that a PhC slab cannot be treated seriously as a flat lens. We also show that by introducing material absorption into the dielectric cylinders of the PhC slab and widening the lateral width of the slab, the imaging uniformity and stability can be substantially improved. This study helps us to clarify the underlying mechanisms of some recently found phenomena concerning imaging instability.