Layered cylinders in a 2D square lattice

摘要

We present the characterization of a photonic crystal slab with a square lattice, whose basis elements are layered cylinders. The cylinders are conceived as glass cores and subsequent layers of two alternating media with different refractive indices, the thickness of each layer is a quarter of a tuning wavelength within the media. The band structure in the dispersion relation is computed by means of numerical simulation and compared to the band structure of a square lattice with plain cylinders, with the same size, and refractive index equal to the average index of the layered ones. We have found that the band structure shrinks to lower frequencies as the number of full periods of layers increases, although keeping the average refractive index and filling factor. This shrink occurs even when the index contrast is kept constant.