Transmission enhancement through subwavelength apertures in infrared range

• Main Authors: Zhi-Huan Lu, 盧致環
• Other Authors: Chieh-Hsiung
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/22081594916157312841

碩士 === 國立臺灣大學 === 電子工程學研究所 === 93 === Metal films perforated with a periodic array of subwavelength grooves or holes have been shown to display enhanced light transmission at selected wavelength. The interaction of the incident radiation with the surface plasmons (SPPs) leads to an enhancement of the transmission. In this thesis I demonstrate control of the transmission properties of a perforated metal film by varying the geometry of the corrugation. In this thesis, experiment results of extraordinary optical transmission through periodically perforated metal film in the middle-infrared and far-infrared region are reported. The position of the transmission pass bands depends slightly on the aperture size but mainly on the periodicity. We also show the transmission spectrum of the device with asymmetric configuration which the lattice constant in x and y direction is different. The position of the transmission pass bands can be examined by a simple formula, and the comparison of experiment results and calculated data will be reported in this thesis. In chapter one, we start with introducing the phenomenon of optical enhancement through subwavelength aperture, and its potential applications. We also explain why we choose the frequency in middle infrared and far infrared.. In chapter two, we introduce the surface plasmons polaritons and its role in the transmission enhancement through subwavelength apertures. In chapter 3, we will describe the device fabrication, and the measurement procedure. The introduction of FTIR (Fast Fourier Transform Infrared Spectrometer) is reported in this chapter. In chapter 4, we discuss different factors that influence the enhanced transmission effect, and we state some argument in order to get more physical insight. Finally, chapter 5 will show the conclusion of this thesis. Furthermore, the suggested advanced research will be proposed also.