Abstract: A lens for terahertz radiation, which can be used in an antenna arrangement, comprises a cylindrical lens body made of silicon having a planar front surface and a planar back surface. The lens body has a front body region which forms a silicon metamaterial with a relative permittivity that decreases in a lateral direction with increasing radial distance from a cylinder axis. A back body region is immediately adjacent to the front body region and extends to the back surface. It consists of bulk silicon having a laterally constant relative permittivity. The front body region comprises holes that are distributed on the front surface in rings that are concentric with respect to the cylinder axis. The holes extend from the front surface to respective hole bottoms at an equal bottom level in a depth direction. The hole bottoms interface with the back body region.

Abstract: A lens (100) for terahertz radiation, which can be used in an antenna arrangement (400), comprises a cylindrical lens body made of silicon having a planar front surface and a planar back surface. The lens body has a front body region (30) which forms a silicon metamaterial with a relative permittivity that decreases in a lateral direction with increasing radial distance from a cylinder axis. A back body region (20) is immediately adjacent to the front body region and extends to the back surface. It consists of bulk silicon having a laterally constant relative permittivity. The front body region comprises holes that are distributed on the front surface in rings that are concentric with respect to the cylinder axis. The holes extend from the front surface to respective hole bottoms at an equal bottom level in a depth direction. The hole bottoms interface with the back body region.