Towards all-dielectric, polarization-independent optical cloaks

Fully enclosing, all-dielectric cloaks working for both E-z and H-z polarizations simultaneously are presented in this letter. The cloaks are effective for two antiparallel angles of incidence, and the layout of standard dielectric material in the cloak is determined by topology optimization. Scattering from cylinder and cloak is reduced for an H-z-polarized wave compared to an E-z-polarized wave by taking advantage of the surface mode at the perfectly electric conducting boundary. Perhaps contrary to simple intuition, fully enclosed, all-dielectric, low-contrast cloaks cannot be designed effectively when distributing a material with lower permittivity than the background material. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3691835]