1 X 2 Beam Splitter With High Efficiency Based On Nonreciprocal Photonic Crystal Waveguide

This paper presents a new method for designing efficient 1 x 2 beam splitter in two-dimensional triangular lattice photonic crystals (PhCs). The proposed splitter is based on the one-way edge mode of gyromagnetic PhC, thus can prevent scattering losses even when there are defects or obstacles in its channels. The incident electromagnetic wave can be evenly split into two output channels as long as structural symmetry is kept in a small area around the Y-junction. The loss effect of gyromagnetic material on the splitting behavior is examined. Moreover, power ratio between the two outputs can be tuned by introducing a defect at a proper position in the splitter. The advantages of the proposed splitter have been validated through numerical simulations.