A Simple Optical Interconnection Integrated with Low Birefringence Silicon-on-insulator Waveguide

5 mum thick silicon-on-insulator waveguide was demonstrated to low birefringence of 4.6times10
^-5
. Instead of complex processing from 3D mode size converter, the high numerical aperture fiber was utilized as the bridge between corresponding waveguide and SMF-28 fiber to get competitively coupling loss of 0.4 dB.