Summary: | 碩士 === 國立彰化師範大學 === 光電科技研究所 === 97 === In this study, the optical transmission characteristics through 2-D photonic crystal slab (PCS) with dielectric and magnetic metal surface, respectively, have been investigated in the visible light region. For the first part, a series of 100 nm-thick freestanding silicon nitride with hexagonal air holes array were fabricated with various lattice constants and hole diameters. As light impinges on the slab normally, the guided resonances are observed in the transmission spectra, in which the resonant wavelengths are appeared in corresponding to the lattice constant of the PCS. Moreover, the absorption dips are splitted and shifted to shorter wavelength by increasing the hole diameters of the PCS. The band structures of PCS calculated by using the plane wave expansion method reveal that the positions of guided resonance and mode splitting behavior are agreed well with the experimental data. For the latter part, the TbFeCo having perpendicular magnetic anisotropy was coated on the PCS with lattice constant of 656 nm and hole diameter of 350 nm. The transmission spectra were measured under an external magnetic field applied parallel to the direction of incident light (normal to the surface of PCS), not only the extraordinary optical transmission (EOT) phenomena were observed, but also the location of transmission peak was shifted to longer wavelength. Up to now, there are rare reports about the EOT through the magnetic material. It is believed that the magnetic photonic crystals are of great interests for understanding the fundamental physics and real applications.
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