The Heterostructure Photonic Crystal Waveguide Splitter

We propose a two-dimensional heterostructure photonic crystal (PhC) waveguide splitter composed of different air-hole radii in the core and claddings. Two PhCs in the core and claddings are treated as two effective homogeneous media in the first photonic band. By using a triangular coupler in the input port, light can be efficiently coupled from the conventional waveguide into the PhC waveguide splitter. Total internal reflections take place at outer interfaces and confine light in the PhC waveguide very well. Finally, incident light is divided into three parts, and each of them couples to output waveguides with total transmission more than 90%.