Photonic Transport Properties In Low-dimensional Photonic Crystals And Waveguide

Photonic crystals (PCs) and waveguides are two most important materials andalso important supporters for photonic transport. They can be fabricated into variousphotonic devices, such as switcher and filter, by using the resonant transmission inphenomena. Therefore, the study of this field has been attracted much attentions. Inthis thesis, we study photonic transport properties in several low-dimensionalphotonic crystal and waveguides, especially the resonant transmission properties, byusing the Green’s function method.The first chapter mainly describes the concept, character as well as application ofphotonic crystals.In the second chapter, we mainly introduced the Green’s function.In the third chapter, we investigate the photonic transport properties of quasi–one dimensional PCs with large permittivity ratio by using the lattice Green’s functiontechnique. It consists of two semi-infinite leads (left and right lead) connected by afinite central scattering region. The finite central scattering region is confined arraysof M (column)×N (row) dots. Interestingly, there are two kinds of resonant peaksappearing in the transmission spectrum. One kind is located in the low frequencyregion, where the photons are mainly localized in the junctions between the dots. Theother kind exists at the high frequency region, which are induced by the highquasi-bound states localized in the intersection of the junctions. These results will behelpful to develop new type of photonic switching devices, multiple channeledfiltering.In the fourth chapter, the photonic transport properties of periodic T-shapedphotonic crystal waveguide was investigated by using the lattice Green’s functiontechnique. It consists of two semi-infinite leads (left and right lead) connected by afinite central scattering region. The finite central scattering region is composed ofperiodic photonic crystals stub and photonic crystals constrain, periodicity number isdefined as n. We first study photonic transport with different periodic number. It wasfound that (n-1) and (n-2) resonant splitting peaks in the transmission spectrum.Interestingly, except for the above two splitting rule, a new (2n-3) resonance splittingpeak appears in the middle of the transmission spectrum. For the (n-1)-fold resonancepeak, it is originated from the quasi-bound state, where the photons are confined in the stub, while (n-2)-fold resonance splitting peak is originated from the quasi-boundstate located in the constraint. As for the (2n-3)-fold resonance splitting peak, it isoriginated from the quasi-bound state mainly localized in the stub and constraint. Inaddition, it is interesting to find that the influence of dots density on photonictransport is efficiency. With the increasing of dots density in the waveguide, theresonance peaks not only shift to the higher frequency region, but also the distancebetween the two kinds resonance peaks become smaller. These results will be helpfulto develop high quality factor of the filter, and low loss waveguide devices.In the fifth chapter, we give a simple summary of the paper and predict theirfuture prospect.