Polarization-Splitting Waveguide Devices Incorporating Perfluorinated Birefringent Polymers

Low-loss perfluorinated polymers with a controllable optical birefringence were synthesized for the purpose of fabricating polarization-splitting waveguide devices, which have become an essential part of polarization-multiplexed coherent optical communications. The birefringent polymer was embedded on one branch of the asymmetric Y-branch waveguide to produce polarization-dependent mode evolution due to the effective birefringence. The device with a branch angle of 1/300 rad and birefringence of 0.007 showed a crosstalk of -25 dB and an insertion loss of 1.5 dB from fiber to fiber. The polarization splitters based on adiabatic mode evolution exhibited negligible wavelength dependence and large tolerance in waveguide dimension.