Two-dimensional photonic crystals: waveguides and guided resonance

A general designing procedure is introduced that allows for any given photonic crystal slab, to create an appropriate waveguide structure that possesses single-mode bands with large bandwidth and low dispersion within the photonic band gap below the light line. The procedure consists of two steps: i) designing a conventional dielectric waveguide that is optimally phase matched with the band gap of the photonic crystal slab; and ii) embedding the dielectric waveguide into the photonic crystal in an appropriate way such that the edge states are eliminated and single mode propagation is ensured. This procedure produces waveguide structures with large bandwidth of single mode and lossless propagation, and creates dispersion relations that are essentially linear over most of the guiding bandwidth.