Model of light collimation by photonic crystal surface modes
Abstract
Description
We propose a quantitative model explaining the mechanism of light collimation by leaky surface modes that propagate on a corrugated surface around the output of a photonic crystal waveguide. The dispersion relation of these modes is determined for a number of surface terminations. Analytical results obtained on the basis of the model are compared to those of rigorous numerical simulations. Maximum collimation is shown to occur at frequency values corresponding to excitation of surface modes whose wave number retains a nonzero real part.
6 pages, 7 figures. Version 2: corrected sign of k_x' (sections 4-6, fig. 2), minor clarifications in section 2. Version 3: significant changes, including reformulation of the model using the theory of aperture antennas, as well as extended discussion of the accuracy of the model
6 pages, 7 figures. Version 2: corrected sign of k_x' (sections 4-6, fig. 2), minor clarifications in section 2. Version 3: significant changes, including reformulation of the model using the theory of aperture antennas, as well as extended discussion of the accuracy of the model