| Summary: | 碩士 === 國立臺灣師範大學 === 光電科技研究所 === 98 === In this thesis, we have three topics. The first one is to study the defect modes in the asymmetric and symmetric multilayer narrowband transmission filters in the simple case of normal incidence. It is based on the wavelength-dependent transmittance calculated by making use of the transfer matrix method. In an asymmetric filter, there exists only one defect mode within the photonic band gap and its position can be changed when the design wavelength is varied. In a symmetric filter, it is found that there are two defect modes. Using Bloch wave approximation, these two defect modes respectively correspond to the symmetric and the asymmetric field solutions in the defect layer.
The second part is to extend the first part to the oblique incidence for the same structures. The defect modes are investigated by the calculated wavelength-dependent transmittance for both TE and TM waves. The dependences of defect modes on the angle of incidence are illustrated. Additionally, the effect of defect thickness on the number of defect modes is also examined.
The third part is to study the angle- and thickness-dependent photonic band structures in a one-dimensional superconducting photonic crystal. It is studied near and below the threshold frequency at which the superconducting material has a zero permittivity. The gap structure is analyzed as a function of the thicknesses of the two constituent superconducting and dielectric materials. In the angular dependence of the band structure, in TM-polarization, there exists a strongly localized superpolariton gap approximately the threshold frequency. This gap is shown to be enhanced as the angle increases.
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