学术文献库

In this paper, the transfer matrix method is used to investigate the reflectance properties in a symmetric defective annular photonic crystal (APC) containing semiconductor, high-$T_c$ superconductor and a radial defect layer. Numerical results offer many noteworthy features that can be very useful in designing optical devices. In this regard, the geometric effects of alternate layers on the optical reflectance of our defective APC structure by changing the thickness of different layers would be investigated. Then, the possibility of controlling the spectral position of existed photonic band gaps (PBGs) and defect modes would be discussed by our analysis. In addition, it is found that the characteristics of the reflectance spectrum and subsequently the spectral position of PBG and defect mode are entirely independent on changes in the starting radius of the hollow core. This characteristic is very attractive to manufacturers, since increasing the size of the core radius would offer flexibility and simplicity of fabrication in producing optical devices. This study reveals that the optical reflectance of defective APCs is strongly dependent on azimuthal mode number. Therefore, our designed defective APC structure works as a perfect reflector for the considerable range of wavelength for higher azimuthal mode numbers. Lastly, our results show that by increase the temperature of superconductor layer both of the existed band gaps and defect mode show a red-shift trend by moving towards higher wavelengths. The proposed structure and related results can lead to gain valuable information for designing and fabrication of new types of annular Bragg resonators surrounding a radial defect and integrated visible waveguide devices like optical switches and filters.