Scattering from sidewall deformations in photonic crystals

We present results from a new method for the solution of electromagnetic scattering from finite sets of twodimensional cylinders exhibiting sidewall deformations. Our model treats the sidewall deviation as a small perturbation on a circle; the response of a single cylinder to an arbitrary external field can then be calculated, and the interactions between the cylinders can be computed with a multipole method. This leads to a series of model problems for successively higher asymptotic orders. Because most of the computation time is taken up with solving the original, unperturbed problem, a large number of additional types of perturbation can be examined at little extra numerical cost. © 2005 Optical Society of America OCIS codes: 250.5300, 230.7370, 230.3120, 290.5880.