An Ultra-broadband Polarization-Insensitive Optical Hybrid using Multiplane Light Conversion

We designed, fabricated and tested a 90 degree optical hybrid using multiplane light conversion. The device supports and octave of bandwidth (900-1800 nm) in simulations. The measured phase errors are below 3 degrees for free space output, and below 8 degrees with a fiber array output, across a measurement bandwidth of 390 nm. The fully packaged device (with input and output fiber arrays) has a measured insertion loss of 5.52 dB at 1550 nm. A high-speed transmission experiment with QPSK format was conducted to verify the performance of the fully packaged device