Effective medium based on two-dimensional photonic crystals for index-confinement waveguide application

Abstract

In this paper, the design of effective microprism based on the subwavelength periodic lattices is proposed. The microprism is realized by using a two-dimensional photonic crystal (PhC) structure with a periodic lattice of air-holes. In order to behave as a homogeneous and isotropic microprism, the PhC structure with a hexagonal lattice should be operated in the low frequency. By monolithically integrating the effective microprism in the bending area of an optical waveguide, its wavefront of eigenmode could be tilted correctly to suppress the radiation loss in wide-angle bent waveguides. In order to demonstrate the feasibility of proposed microprism for low-index-contrast waveguides, an example of bent waveguide with the eigenmode nearly compatible to the single mode fiber is adopted to design the PhC microprism. The transmission efficiency as high as 92% for the proposed structure with the bending angle of 12.96° and the bending radius of 89.09 μm is achieved.