Photonic Crystals Composed Of Dispersive Materials

The properties of photonic crystals composed of different dispersive materials are investigated in this thesis. The content includes three parts:⑴Transmission properties of one-dimensional photonic quantum wells consisting of dispersive materials,⑵transmission characteristics of two-dimensional finite photonic crystal slabs containing negative epsilon materials, and⑶dispersive relations of infinite photonic crystals fabricated from negative epsilon materials.First of all, the transmittances of one-dimensional photonic crystals made up of dispersive materials are calculated by using the transfer matrix method. Then the quantum well structures are produced by inserting defect layers into perfect dispersive photonic crystals mentioned above. The defect layers possess different periods consisting of only one kind of dispersive material or another kind of dispersive photonic crystal. It has been turned out that photonic band gaps exist and the confined states are quantized in the quantum well structures. When the negative index materials are included in the well structures, whether the well is composed of this kind of dispersive layers or it is another kind of photonic crystal containing this dispersive material, the number of the confined states increases monotonously with the increasing period of the defect layers. While in other photonic quantum well structures the number of the confined states is independent of the well period.Secondly, the transmittances of two dimensional photonic crystal slabs containing negative epsilon materials setting on square crystal lattice are calculated employing the finite difference time domain (FDTD) method. The simulation results indicate that photonic crystal slabs holding square and rectangular scattering pillars present band gaps whether the pillars are composed of negative epsilon materials or the backgrounds are negative epsilon materials on the condition that negative epsilon materials are in proper proportion. This phenomenon can be viewed as the effect of both the absorptions of negative epsilon materials and the scattering of the pillars. When the pillars correspond to negative epsilon materials and the background to vacuums, the frequency numbers of the transmitted light band decrease with the filling factor of scattering pillar increasing. The transmittances in wide frequency range approach to zero the moment that the filling factor reaches a higher value. When the background corresponds to negative epsilon materials and the pillars to vacuums, the quantity of the transmitted light in lower frequency range rises intensively.Finally, the dispersive relations of the infinite photonic crystals comprised of negative epsilon scattering pillars embedded in the square crystal lattice are investigated by the expanded basis plane-wave method. The pillars are in the shape of square, rectangle, and cylinder. The calculated results reveal that the band gaps exist in the photonic crystals containing negative epsilon materials, and it has a wider tendency when the size of the scattering pillars becomes larger, and the central positions of the band gap move upward simultaneously.