Enhanced Transmission Throuth SUB-Wavelength Strips Periodic Array On Metallic Mediums

Accompany with the rapid development of nano-Optics and Materials Science, researches in sub-wavelength nanostructure fascinates great interests among those focusing in related areas, which including the recent efforts in Surface Plasmon’s discussions. Nowadays there have been already developed many technique methods based on Surface Plasmon effects. They are working as products in bimolecular detection, material chemical composition analysis, optical sensing, silicon-based solar cells and related areas of science experiments. Surface Plasmon is to be considered to be a bridge between optical information technology and electronic processing system which provides a theoretical possible method to set up a function realizing the integration of optical devices in circuits.A nanostructure with strips periodic array of silicon oxide embedded on metallic substrate is studied in method of FDTD.According to the finding that the curve of transmission spectrum shifts with varieties of strips’figuration; this structure can be used as a filter by designing the parameter of the strips. Consequently, the narrowband of the frequency we want is remained and enhanced. By using the rigid full-vectorial three-dimensional finite-difference time-domain method (FDTD), we show the enhanced transmission spectra through a metallic film with a periodic array of subwavelength holes with linear mediums result two different resonances:localized waveguide resonances and surface plasmon resonances due to the periodicity. Filling the subwavelength holes with the glass from the bottom, we show the enhanced transmission spectrum in two different calculation models. The result exhibits that the low frequency peaks of the enhanced transmission spectrum move obviously while the high frequency peaks of the enhanced transmission spectrum do not move evidently. This kind of structure could be used as a controllable filter in optical communication. A multi-layer hole periodic array might be helpful dealing with flatness-transaction of optical signal amplification.