金屬與介電質層狀結構表面電漿波光學性質之研究

Abstract

本論文主要使用稜鏡耦合的方式來激發表面電漿波，分別用使用了Kretshmann結構以及雙層金屬結構，材料方面則選用了Ag、LiF、Au、ITO、InN等，藉以探討不同結構、金屬材料、厚度、入射光波長下，表面電漿的各種光學性質變化。 第二章針對表面電漿的各種基本性質進行研究，包括表面電漿波及長程表面電漿波的激發、對稱結構的色散關係、Ag薄膜及LiF薄膜的改變對反射率、共振角位移、半高寬度等之影響。 第三章使用雙層金屬薄膜結構( MgF2 / Ag / Au )和Kretshmann結構(Au)，確認在能量損耗、反射率等方面，雙層金屬薄膜結構能夠提供較佳之表現，並改變Ag及 Au之厚度，探討其對反射率曲線造成之影響。 第四、五章針對應用於紅外光區的InN及ITO材料，分別針對兩者靈敏度最佳的頻段，探討薄膜厚度的變化對於靈敏度的影響，並找出表現最佳之值。In this thesis, we use the Kretshmann structure and the bilayer metallic structure to excite the surface plasma waves (SPW), respectively. The materials used are Ag, LiF, Au, ITO, and InN. By changing the wavelength of the incident light, the thin film materials and their thicknesses, we can study the optical properties of the surface plasma wave. In Chapter 2, we first study the basic properties of the SPW, including the excitation of SPW, long-range SPW, and the dispersion relation of symmetric structure. The properties such as the resonance angle displacement and FWHM can be examined by the calculated reflectance. In Chapter 3, we make a comparison between bilayer metallic structure (MgF2 / Ag / Au) and the simple Kretshmann structure (Au). Considering the energy loss and reflectance, it is found that the bilayer metallic structure can provide better performance. In Chapter 4 and 5, we respectively chose InN and ITO to replace the metal and properties of SPW can be investigated in the regions of 1500nm -1800nm for ITO and 2500nm - 5500nm for InN. The sensitivity issues will be explored for these two materials.