多層膜遠離式光柵系統之表面電漿耦合

Abstract

近年來，光通訊傳遞波導管與生物感測器的開發、設計成為關注的議題。我們利用有限時域差分法模擬並設計多層膜之遠離式光柵結構，能量可以藉由全反射共振有效地被激發到兩層介電質間，以達到表面電漿多重窄頻寬共振之效應。使其能擁有多重波長感測器的功效，以及在介電質表面能有效的傳遞表面電漿子，希望這些好處未來能被應到相關領域。我們所提出的結構，藉此探討不同類週期排列與不同介電質膜厚對遠離式光柵的場強效果，且最佳化結構得到最大場強，並探討增強的原因與物理機制。藉由模擬數據分析，我們發現不同介電質膜厚以及不同類週期遠離式光柵的排列為影響共振耦合頻率的兩項重要因素。

Currently, the plasmonic waveguides are able to transmit or to control the optical or electronic signals; the plasmonic device can be used as bio-sensors, both of which have become popular issue. In this research, I simulate and design multilayer remote-grating system by using finite-difference time-domain method. The power flow can perfectly be excited to interface between two dielectric materials by total reflection. Then, it can reach multiple narrow band coupling of surface plasmons, which obtain the functionality of multiple wavelength sensor. SPPs have ability to transmit on the surface of dielectric material with low loss. Hence, I hope that these advantages can be applied to related field in the near future. First, I discuss the relationship between different quasi period arrangements and different thickness of dielectric layer toward the intensity effect of electric field of remote grating system. Afterward, we can get the maxima enhancement by optimizing the parameters as well as investigate the physical mechanism and the reason why I can enhance the electric field intensity. From our simulation analysis, there are two important reason of influencing on coupling frequency that I find different thickness of dielectric layer and different quasi period remote grating arrangements.