spatial-division-multiplexing (SDM) optical transmission with multiplexed orbital angular
momentum (OAM) states over a topological charge range of− 2 to+ 2. The silicon PIC
fabricated using a CMOS-compatible process exploits tunable-phase arrayed waveguides
with vertical grating couplers to achieve space division multiplexing and demultiplexing. The
experimental results utilizing two silicon PICs achieve SDM mux/demux bit-error-rate …