Study Of The Transmission Properties Of Photonic Crystal With Media Chirality

Recently, as an artificial photonic device with excellent performances, photonic crystal (PC) are found promising application in many fields, e.g., optical communication, which arouse intensive interests. For their special optical properties, the materials with media chirality or structural chirality are also the one of the hot spots in international academe. Particularly, the investigation of chiral photonics devices are caught many researchers'attention.In this thesis, based on pseudospectral time-domain (PSTD) method and plane-wave expansion method, the transmission properties of one dimensional (1D) and two dimensional (2D) chiral PC are studied.Firstly, the current research situation on PC and optical chirality is summarized, and the background and the significance of our subject are emphasized. We classify the optical chirality conceptually, and briefly illustrate the definition and the development of media chirality or structural chirality.For the purpose of introducing the numerical methods into computing the chiral photonic crystal, we study the constitutive equation of a bi-isotropic chiral medium in detail. Because the eigenmodes in the chiral medium are left- and right- circularly polarized light (LCPL and RCPL), we deduce the discrete equations suitable for BI-PSTD method and described the chiral plane-wave expansion method based on the decomposition of circularly polarized light.By using BI-PSTD method, the bandgap structure of 1D chiral PC is discussed. In the simulation, the bandgap separation in the linear PC with different layers is exhibited. Because of the existence of sidelobes in such a kind of PC, the technique of using envelop function is applied to suppress them. Furthermore, the approach that can realize apodization at both the high frequency and low frequency sideband is also explored. The field distribution in the PC, after introducing the chirality and the apodization, is investigated also.Based on plane-wave expansion method, the bandgaps of 2D chiral PC are studied in detail. Since the substrate and the padding can be chosen as with or without chirality, there are different combinations of chiral PC. Correspondingly, the bandgap structures for LCPL and RCPL are calculated in the situations of square, triangular, and honeycomb lattices. Moreover, the effect of chiral parameters on bandgap separation and full-stopband is discussed too.At last, the bistable behavior in the 1D chiral PC is investigated, and the scheme of all-optical switch based on apodized sideband is also proposed. Utilizing the difference in the bandgaps between the LCPL and RCPL, we design the polarization sensitive chiral PC waveguide devices with line defect.