Low loss multilayer frequency selective surface negative index metamaterials for the mid-infrared

A metamaterial structure using five cascaded FSS screens was proposed and optimized by a GA to have an index of refraction of −1 with low absorption and mismatch losses in the mid-IR. Measured dielectric and metallic properties incorporated into the model provide confidence that the PFEBI predictions are accurate. Extension of the design to six screens indicates that the effective properties are approaching those of a bulk material. Efforts are currently underway to fabricate and test a multilayer FSS NIM.