Wideband Adjoint Sensitivity of Dispersive Structures Using FDTD Method

We present a novel FDTD-based adjoint sensitivity analysis approach of dispersive structures. Only one extra FDTD simulation is required to estimate the wideband sensitivities of the desired objective function or response with respect to all dispersion parameters, material parameters, and shape parameters. Our approach does not utilize the wave equation and is based directly on Maxwell's equations. This approach is illustrated here through one example.