Wideband cloaking of objects with arbitrary shapes exploiting adjoint sensitivities

We propose an effective approach for optimal wideband cloaking of objects with arbitrary shapes exploiting adjoint sensitivity analysis. Our method optimizes the voxel-by-voxel constitutive parameters of an anisotropic cloak resulting in a large number of optimizable parameters. The associated sensitivities of a wideband cloaking objective function are efficiently estimated using our in-house anisotropic adjoint variable method (AVM) simulator. Only one adjoint simulation is needed regardless of the number of required sensitivities. A gradient-based optimization algorithm utilizes the available sensitivity information to iteratively improve the wideband cloaking objective function and to determine the constitutive parameters of the optimal cloak.