16-QAM-Carrying Orbital Angular Momentum (OAM) Mode-Division Multiplexing Transmission Using All-Fiber Fused Mode Selective Coupler

We demonstrate mode-division multiplexing (MDM) transmission exploiting orbital angular momentum (OAM) modes with low loss and negligible mode crosstalk. An all-fiber fused mode selective coupler is fabricated and employed as an efficient OAM mode multiplexer/demultiplexer.