Fig. 7From: High-permittivity ceramics enabled highly homogeneous zero-index metamaterials for high-directivity antennas and beyondPhotograph, simulated and experimental results of a DCZIM-based concave lens. a Photograph of the DCZIM-based concave lens sample. b measured field, c simulated field intensity in the near-field region over the top surface of the concave lens sample. Black circles indicate the positions of SrTiO3 pillarsBack to article page