One-way absorption properties in asymmetric single-negative-based Cantor photonic crystals

Abstract

In this work we theoretically study the one-way optical properties in asymmetric triadic-Cantor-set (TCS) photonic crystals (PCs), air/TCSN/G/TCSM/air, where TCSN is the stage N TCS composed of a lossy epsilon-negative (ENG) material and a lossy mu-negative (MNG) material. In addition, the defect layer G is a dielectric. Our results show that the absorption spectra are different in forward and backward propagation. Specially, it is first discovered that the one-way properties will disappear if the layer thicknesses are large. Besides, the layer thickness limit is smaller when the TCS stage is larger. Additionally, comparing with previous studies, we find that the type of interaction between the defect and non-defect modes is decided by the layer materials of the PC structure.