The high-transmission photonic crystal heterostructure Y-branch waveguide operating at photonic band region

Abstract

We design a high-efficiency two-dimensional photonic crystal (PhC) Y-branch waveguide formed as a heterostructure with two different triangular PhCs composed of air holes. At photonic-band frequency regions corresponding to circular equifrequency surfaces, the two PhCs could be taken as effective homogeneous media with effective refractive indices. A triangular coupler composed of the PhC is designed at the input port in order to divide the incident beam into two parts. The two parts finally propagate into different channels. A case demonstrated here shows that the total transmission of light passing through the Y-branch waveguide is about 91.2%. The propagation phenomena can be explained by the mechanism of total internal reflection very well. (C) 2011 American Institute of Physics. [doi:10.1063/1.3532048]