Guided-mode resonance excitation on multimode planar periodic waveguide

Planar periodic waveguides are applied to design numerous passive guided-mode resonance (GMR) elements. Key to achieving these devices with desired spectral properties is placement and manipulation of the resonance peaks. It has been shown that, the resonance locations closely track the dispersion curves of the leaky modes. In this paper, taking Bragg reflection due to periodicity and coupling between different modes into account, we investigate the dispersion relations of leaky modes in multimode planar periodic waveguides, both for s-polarized (TE mode) and p-polarized (TM mode) incident waves. Exploiting the characteristics of leaky mode dispersions in full range of the first Brillouin zone, we offer the ways to construct some novel optical elements, for example, polarization independent and angular tolerant GMR filters. (C) 2010 American Institute of Physics. [doi:10.1063/1.3483958]