| Photonic crystal is a new type of artificial microstructure material with characteristic of photonic bandgap (PBG) structure. And it has peculiar ability of inhibiting spontaneous radiation of atoms and controlling light propagation. It will be widely used in the fields of optical communication, microwave communication, integration optical and many others. One-dimensional (1D) photonic crystal can be made easily due to its simple structure and has the properties of 2D and 3D photonic crystals. This novel optical materials will probably be crucial components in the field of optical communication, so the relevant theoretical researches are valuable and wide application perspectives are expected.The summary of the dissertation is as follows:1 .The historical background, the physical foundation and the main properties (photonic bandgaps and photonic localization) of photonic crystals are introduced in chapter I. Different design methods and different theoretical research methods are also compared in this chapter. Finally, possible utilization and main research fields in photonic crystal are listed so that we can set the aim of the present thesis.2. Chapter II starts from the Maxwell's equation, deduces the basic differential equation of light spreads in photonic crystal and the theory of one dimensional optical transfer matrix. This theory has small calculation quantity and high precision in calculation and may calculate photonic bandgap properties of photonic crystals.3. We discuss the influence of disorder on one dimension photonic bandgap in Chaper III.(a) By introducing structural parameter a, photonic bandgap properties of disordered 1D binary photonic crystals are investigated. Widely extended by the disordered structure, the photonic bandgap is over 2 times larger than that ofordinary photonic crystals. It is found that the disordered 1D photonic crystals with proper periodic structure display high reflective characteristics from visible to infrared. The influence of incident angle and degree of disorder D to the photonic bandgap are also computed and discussed. The relative width of bandgap becomes smaller as incident angle increases, but it always maitains above 62.5% when incident angle is in the range of zero and π/3. The results show that the HRR becomes wider When D is greater than 4.63%, some defect modes emerge in HRR; when D is 3.66%, a clear best HRR is obtained.(b) By introducing structural parameter a,b, bandgap properties of disordered 1D ternary photonic crystals are investigated for the first time to our knowledge. The results obtained show that disordered structure provide strikingly extended bandgap compared with the corresponding periodic structure. The more the number of disordered dielectric multilayers we adopted, the wider the stop band we will be obtained. The influence of degree of disorder D and contrast of high and low refractive indices to the photonic bandgap are also calculated and discussed. The relative width of bandgap becomes smaller as incident angle increases, but it always maitains above 60.5% when incident angle is in the range of zero and π/4. The results show that the HRR becomes wider When D increases, the HRR tends to shift towards both the high and low frequency range.4.We investigate photonic bandgap properties by using for reference the concept of semiconductor quantum-well and heterostructure and constructing photonic crystal of heterostructure and of quantum-well structure by using different sub-photonic crystal in chapter IV. They display new characteristics different from photonic crystals with ordinary structures.(a) Photonic crystal of quantum-well structureIt is possible to enlarge the range of low transmission in one-dimensional photonic crystals by using photonic quantum well structures. Multi channel filtering can be obtained in 0.3-0.45Hz and 0.55-0.7Hz frequency range in such a quantum-well photonic crystal under proper operating parameters. |
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