Fiber optics Optical fiber communication Equipment and supplies Management Telecommunication systems 28 GHz Electrical & Computer Engineering Engineering & Applied Sciences MIMO OAM OAM-MIMO Optical communications Optical fiber communication -- Equipment and supplies Pancharatnam-Berry optical elements Poincaré sphere Telecommunication systems -- Management Telecommunications bi-isotropic media chirality dielectric lens dual symmetry electron beam lithography free-space optical communications frequency-domain helicity interpolation light-matter interactions long period fiber grating metasurfaces microstructure optical fiber