摘要: | 本論文利用表面電漿共振 (Surface Plasmon Resonance, SPR) 能夠增 強 Goos-Hänchen 效應 (Goos-Hänchen Effect, GH Effect) 的能力,結 合其本身多年來於生物樣本檢測領域的應用,以偏振光學、GoosHänchen 效應、表面電漿共振以及干涉光學的理論為基礎重新設計實 驗,並且重新定義一物理量 Kaisa 作為新的檢測依據。 實驗設計中,將一道擁有兩個偏振模態 (TE and TM Mode) 的雷 射光束導入 Kretschmann Configuration,原入射雷射光由於表面電漿 共振 (Surface Plasmon Resonance, SPR) 對於兩偏振態會造成不同程 度的 Goos-Hänchen 效應的位移現象,在雷射光離開 Kretschmann Configuration 時,原入射光由原先兩個偏振模態正交的一道雷射光一 分為二,形成兩道偏振模態正交的雷射光束,且兩道雷射光束間部分 面 積 重 合 。 並 且 在 Kretschmann Configuration 後放置 GlanThompson Polarizer 使 TE 偏振模態和 TM 偏振模態分別單獨通過, 以及兩偏振模態同時通過,使其兩於同方向量上產生分量進行干涉。 最終由偵測器量測 TE 偏振模態和 TM 偏振模態的反射光吸收光 譜以及干涉後干涉項的光強。而 Kaisa 即為干涉項的光強除以兩倍 的 TE 偏振模態和 TM 偏振模態的反射光強相乘的開根號。 經由理論模擬後計算後,原先作為檢測依據的 TM 偏振模態的 iii 反射光強的品質因數 (Figure of Merits, FoM) 為 37.12,而 Kaisa 的 品質因數則為 114.67,相較原檢測依據的品質因數提升了 3.09 倍。 實際實驗量測中,以蔗糖水溶液作為量測樣本,樣本濃度分別為 0%、 1.25%、2.5%、5%以及 10%,其對應折射率為 1.33299、1.33478、1.33659、 1.34026 以及 1.34783。而此實驗架構量測折射率變化的檢測極限 (Limit of Detection, LoD) 可達 1.05 × 10−3 RIU (Refractive Index Unit)。;This work adopted the concept of Goos-Hänchen effect into the Surface Plasmon Resonance biosensor. The experimental design is based on the theory of the Polarization of Light, Goos-Hänchen effect, Surface Plasmon Resonance and Interferometry. And a new parameter, Kaisa, is introduced and defined. In the experimental design, a laser beam with both TE and TM polarization mode serves as the incident light source arriving at the Kretschmann Configuration. Since the Surface Plasmon Resonance introduce different Goos-Hänchen shifts to the laser beam with TE and TM polarization mode, the incident laser beam is split into two beams with TE and TM polarization mode respectively. Moreover, there is a slight spatial shift between them. After the Krestchmann Configuration a GlanThompson Polarizer is placed to allow only the beam with TE or TM polarization mode to pass, and create the component on the same direction for both beam to interfere with each other. At last the detector will measure the power of the beam with TE and TM polarization mode respectively and the power of the interference term. The new parameter, Kaisa, is then defined as the power of the interference term divided by two times of the square value of the product of the power of the beam of TE and TM polarization mode. According to the theoretical calculation and simulation, the Figure of Merit (FoM) of the power of the beam with TM polarization mode, which is commonly used as the parameter for Surface Plasmon Resonance biosensor testing is 37.12, meanwhile, the FoM of Kaisa is 114.67, v indicating increasing the resolution of the biosensor by 3.09 times. In practice, the sucrose solutions are selected as the testing sample, with the concentration of 0%, 1.25%, 2.5%, 5% and 10%, and the corresponding refractive index will be 1.33299, 1.33478, 1.33659, 1.34026 and 1.34783 respectively. The Limit of Detection (LoD) of the system is able to reach 1.05 × 10−3 RIU (Refractive Index Unit). |