Tunable properties of one-dimensional GaAs/AlAs-based photonic crystal containing two defect layers

Abstract

The characteristics of an optical tunable filter are elicited theoretically in this study. Here, the characteristic matrix method is used to investigate the behavior of the defect modes in GaAs/AlAs-based one-dimensional defective multilayered photonic crystals consisting of two externally magnetized GaAs defect layers. The external magnetic field is applied to GaAs for the consideration of the defect mode in the middle of the structure. The effects on the defect modes for distinct values of the external magnetic field, electron density, and angle of incidence for both the TE and TM waves are analyzed. The numerical results convey that the frequency of the defect mode can be tuned effectively by changing the values of the physical parameters. Besides, the modes of propagation play a major role in the shifting trend of occurrence of the defect modes in the higher frequency region. The contour plots for electron density and incident angle show two clear defect peaks for both TE and TM waves. Moreover, the Brewster angle verifies the complete transmission through the defective symmetric optical media. The proposed structure can be used to design the narrowband and multichannel tunable transmission filters at the terahertz region.