Silica Waveguide Four-Mode Multiplexer Based on Cascaded Directional Couplers

Mode multiplexers/demultiplexers (MUX/deMUX) are key components in mode division multiplexing. A silica waveguide MUX consisting of four cascaded directional couplers is experimentally demonstrated. The beam propagation method used the device design and optimization. Thermal oxidation, plasma-enhanced chemical vapor deposition, ultraviolet photolithography adopted fabrication. measurement results prove that input E00 can be selectively converted to E10 mode, E20 E30 mode. Within wavelength range 1500 1620 nm, insertion loss less than 12.2 dB. proposed has good potential on-chip MDM applications.