Fig. 4From: Planar metasurface-based concentrators for solar energy harvest: from theory to engineeringa Principle of the detour phase. b Schematic of the detour phase metasurface for dual-polarized vortex beam generation. a Reproduced with permission [129]. Copyright 2016, Wiley-VCH. b Reproduced with permission [130]. Copyright 2022, IEEEBack to article page