High-Efficiency Low-Crosstalk 1310-nm Polarization Splitter and Rotator

We demonstrate the first example of a polarization splitter and rotator (PSR) at 1310 nm built on a silicon-on-insulator platform using 248-nm deep-ultraviolet lithography. The PSR is constructed with a directional coupler, a bilevel taper-based TM0-to-TE1 mode converter, and an asymmetric Mach-Zehnder-based TE1-to-TE0 mode converter. A worst-case TM0-to-TE0 mode-conversion loss of 2 dB, with polarization crosstalk lower than -20 dB over a wide bandwidth of 40 nm is experimentally demonstrated. The worst-case polarization-dependent loss is 0.76 dB.