A 1 × 2 polarization-independent power splitter using three-coupled silicon rib waveguides

This work presents the development of a three-waveguide polarization-independent 1 × 2 power splitter using the silicon-on-insulator platform. Design of the device was accomplished by the effective index based matrix method and coupled mode theory. The component was fabricated using a readily available silicon-on-insulator substrate of a 5 μm thick device layer and characterized at 1.55 μm wavelength of light. The fabricated device has an insertion loss of 11.43 dB for transverse electric (TE) polarization and 11.80 dB for transverse magnetic (TM) mode, which indicates its polarization-independent behavior. The power splitting shows an imbalance of 0.23 dB for the TE mode and 0.82 dB for TM mode, which is due to the fabrication error of the separation of outer arms from the central input waveguide. The design can be extended for any 1 × 2N 3-dB power splitter, which will be very useful for optical interconnects and fiber-optic communication networks.