Photonic crystal device sensitivity analysis with Wannier basis gradients.

We present a powerful sensitivity analysis method for devices in a photonic crystal. The method is based on a Wannier basis field expansion and efficient matrix analysis techniques for finding eigenvalue and transmission gradients with respect to the perturbation. The method permits fast analysis of a large number of dielectric perturbation situations for multiple devices in a photonic crystal. We verify the method with finite-difference time-domain and plane-wave expansion calculations.