| Since its discovery in 1998, the phenomenon of extraordinary optical transmission has arroused a worldwide enthusiasm to research on its physics mechanism and its application. This work emphasizes on the study of the mechanism of extraordinary optical transmission through periodic and quasiperiodic subwavelength hole array in metal films.Classical coupled-wave theory is used to analyze the coupling process between light and the surface plasmons wave on metal films with hole array. The analysis shows clearly the physical mechanism of extraordinary optical transmission is that the SPP plays the main roll in this process. The calculation demonstrates that, instead of energy flux directly passing through the holes, the electromagnetic modes could exchange energy by overlapping the evanescent fields under the assistance of hole array. The periodicity of the array provides the momentum-matching condition to present the transmission peaks. The theory exhibits a good agreement with the experimental results reported and is simple and clear.Extraordinary optical transmission on quasiperiodic-structured metal film is also studied. The feature of extraordinary optical transmission of Fibonacci chain of subwavelength holes on metal film was theoretically investigated. Owing to the multiple phase-matching mechanism in Fibonacci chain, the multifractal transmission property is found. The scaling effect on transmission spectrum with increasing Fibonacci sequence is obtained at the quarter-wavelength optical thickness. This behavior can be considered as the evidence for the localization of the surface plasmon mode on quasi-periodic structure, which was verified using FDTD simulation. Because of the possibility to predict the spatial distribution of localized plasmon modes through the transmission spectrum in quasi-periodic structure, this study has a significant impact for the design and fabrication of novel nano-plasmonic devices. Using metallic film perforated with sub-wavelength periodic structure, a novel concept color filter for multi-color OLED display is proposed. Based on the phase-matching condition for extraordinary optical transmission, three primary color emissions can be obtained by optimizing the structure's periodicity. Discussion is presented to improve the purity of these filters. It is important that this type color filter simultaneously fineness the low emission efficiency problem for OLEDs with the aid of enhanced transmission of metal film.Optical transmission properties of sampled-period subwavelength metallic hole array have been studied using Fourier transform analysis. The multiwavelength enhanced transmission feature is found, which is due to multiple phase-matching in this structure. Through changing the sampling parameters, the interval between transmission peaks and the intensity distribution can be adjusted for special applications. It is important that a novel kind of multi-wavelength optical micro-filter has been proposed to exploit the application of periodic hole array structure. Based on this special structure, a novel optical filter is also developed for dual-wavelength fluorescence-spectrometry, structure parameters are analyzed to meet the requirement of dual-wavelength transmission in mTASs. With the features both to enhance the fluorescence generation and to enhance light transmission, in addition with the feasibility for miniaturization, integration on one chip and mass production, the proposed filters are promising for the realization of dual-wavelength fluorescence- spectrometry in micro-total- analysis-system. |
