含耦合及量子井缺陷層之光子晶體多通道光學濾波器之研究

Abstract

In the last two decades, the periodically arranged dielectric structures known as photonic crystals (PCs) have found their potential applications in various optoelectronic devices. The devices make use of the features of photonic band gaps (PBGs) originating from the periodic nature of PCs. When the periodicity is broken by introducing a defect into the PCs, a defect mode will appear inside the photonic bandgap and this is analogous to the electronic impurity state of semiconductors. In this thesis, we consider different defective photonic crystals that can work as a multichanneled filter. Three main topics will be involved. The first structure called the impurity band-based photonic quantum well (IBBPQW) is (AB)m(ABAC)nABA(BA)m , where AB denotes the unit cell, C denotes the defect, and the number of defects is n. The IBBPQW can make more effective use of the localization properties of the electromagnetic (EM) field. The IBBPQW structure can be constructed with great freedom since the impurity band is naturally located inside the gap and the bandwidth of the impurity band can be tuned by changing the separation between the defects and the size or refractive indexes of the defects. In the second structure, we shall consider the photonic quantum-well as a defect in a host PC, i.e., (AB)m(CD)n(AB)m . If the photonic pass band of the photonic crystal(CD)n is just located into the photonic band gap of the photonic crystal (AB)m, quantized confined photonic states will appear owing to the photonic confinement effects. It is found that the number of the confined states can be tuned by adjusting the number of period of the well region, leading to the phenomena of multiple channeled filtering. In the third part, we continue to examine the other condition that the photonic pass band of the photonic crystal (CD)n is partially located into the photonic band gap of the photonic crystal (AB)m. In this case, the number of the confined states can be again tuned by adjusting the number of period of the well region, leading to the phenomena of multiple channeled filtering. However, the number of channels is not the same as the second case. A different design rule will be provided. The whole theoretical analysis in this thesis is based on the transfer matrix method which will be given in Chapter 2. Chapter 1 is to give a brief introduction of PCs. Three main topics are given in Chapters 3, 4 and 5, respectively. The conclusion is in Chapter 6.In the last two decades, the periodically arranged dielectric structures known as photonic crystals (PCs) have found their potential applications in various optoelectronic devices. The devices make use of the features of photonic band gaps (PBGs) originating from the periodic nature of PCs. When the periodicity is broken by introducing a defect into the PCs, a defect mode will appear inside the photonic bandgap and this is analogous to the electronic impurity state of semiconductors. In this thesis, we consider different defective photonic crystals that can work as a multichanneled filter. Three main topics will be involved. The first structure called the impurity band-based photonic quantum well (IBBPQW) is (AB)m(ABAC)nABA(BA)m , where AB denotes the unit cell, C denotes the defect, and the number of defects is n. The IBBPQW can make more effective use of the localization properties of the electromagnetic (EM) field. The IBBPQW structure can be constructed with great freedom since the impurity band is naturally located inside the gap and the bandwidth of the impurity band can be tuned by changing the separation between the defects and the size or refractive indexes of the defects. In the second structure, we shall consider the photonic quantum-well as a defect in a host PC, i.e., (AB)m(CD)n(AB)m . If the photonic pass band of the photonic crystal(CD)n is just located into the photonic band gap of the photonic crystal (AB)m, quantized confined photonic states will appear owing to the photonic confinement effects. It is found that the number of the confined states can be tuned by adjusting the number of period of the well region, leading to the phenomena of multiple channeled filtering. In the third part, we continue to examine the other condition that the photonic pass band of the photonic crystal (CD)n is partially located into the photonic band gap of the photonic crystal (AB)m. In this case, the number of the confined states can be again tuned by adjusting the number of period of the well region, leading to the phenomena of multiple channeled filtering. However, the number of channels is not the same as the second case. A different design rule will be provided. The whole theoretical analysis in this thesis is based on the transfer matrix method which will be given in Chapter 2. Chapter 1 is to give a brief introduction of PCs. Three main topics are given in Chapters 3, 4 and 5, respectively. The conclusion is in Chapter 6.