Multiband unidirectional cloaking based on geometric optics

摘要

A unidirectional transmission cloak composed of transparent prisms is proposed to provide invisibility of objects with dimensions substantially exceeding the wavelengths of incident radiation. Instead of accelerating waves inside the cloak medium to avoid detectable wave front distortions beyond the cloak, as metamaterial based cloaks do, the designed cloak provides the uniformity of wave phases by delaying the wave phase in the cloak medium by multiple of 2π versus wave phase in free space. The efficiency of the cloaking effect is confirmed by appearance of multiband drops in the simulated spectra of the total scattering cross-width of the cloaked objects.