Unidirectional light beam splitting characters of the two-dimensional hybrid photonic crystal structures

Abstract The unidirectional light beam splitting characters of the two-dimensional photonic crystal structures consisting of silicon rods immersed in air are studied. Through interlacing the silicon rods with different radiuses at the interface of the two photonic crystal structures, the unidirectional light beam splitting phenomena towards two opposite forward directions within different frequency regions are achieved. A novel three-channel beam splitting behavior is also observed. The theoretical analysis shows that the self-collimation effect plays an important role in the high-quality beam splitting behaviors. And the influence of the alteration of period’s length to the light beam splitting effects is also studied, through which the working frequency and the two split light beam’s propagation direction can be changed simultaneously.