Optimization of a two-dimensional photonic-crystal waveguide branch by simulated annealing and the finite-element method

The finite-element method including simulated annealing algorithm is adopted for the analysis and optimization of photonic-crystal waveguiding structures. The dispersion relations of the photonic-crystal waveguides are found by solution of an eigenvalue equation. The waveguide structures including bends and branches are analyzed by use of a scattering formulation. The symmetry of the structure is exploited to classify the modes as well as to reduce the computations. Based on the transmission spectra of a waveguide's bends and branches, a branch is optimized by use of the simulated annealing algorithm. (C) 2004 Optical Society of America.