PLC-Based Four-Mode Multi/Demultiplexer With LP11 Mode Rotator on One Chip

We propose a PLC-based mode multi/demultiplexer (MUX/DEMUX) for mode-division multiplexing. We show numerically that the PLC-based mode MUX/DEMUX with a uniform height on one chip can multi/demultiplex four modes (LP₀₁, LP₁₁a, LP₁₁b, and LP₂₁a) by using our proposed LP₁₁ mode rotator and a parallel waveguide. We successfully multi/demultiplex the four modes and achieve a relatively low-wavelength dependence over the C-band by using our fabricated four-mode MUX/DEMUX.