Study On Broadband Carpet Cloak For Transverse-electric Polarization

Based on transformation optics,we can design perfect cloaks that can hide an object from observation.The designs of free standing cloaks generally requires anisotropic and inhomogeneous materials.These requirements are very difficult to implement in practical and will limit the cloaking bandwidth to an impractically narrow range.To overcome this problem,a new strategy called carpet cloaking was proposed.To meet the broad bandwidth demand,magnetism has been fully abandoned in previous demonstrations of macroscopic carpet cloaking.However,in practical applications,it requires that the invisibility cloaks can work on a broad bandwidth for full polarization.It is necessary to study the broadband carpet cloaks for TE polarization.In this dissertation,we investigate a way to design a broadband carpet cloak for transverse-electric polarization.Using closed ring structure,we design a low-loss metamaterial which can work in broadband.We experimentally demonstrate a broadband carpet cloak for the TE polarization.The cloak is made of non-resonant closed-ring metamaterials with little dispersion and the cloaking performance is confirmed with both time-domain simulation and frequency scanning measurement over a broad bandwidth corresponding to a pulse signal illumination.