多模錐形光纖感測器製作與特性之研究

Multimode Tapered Fiber Sensor

江嘉琪(CHIA-CHI CHIANG)

指導教授 ： 湯兆崙

國立中正大學/理學院/物理學系/碩士(2012年)

摘要

光纖修飾金奈米生化感測器是使用定域化表面電漿共振原理，使金奈米粒子吸收光纖表面漸逝波，進而增強光纖對折射率感測的靈敏度。為了提升光纖感測器的靈敏度。
在本論文中，我們將多模光纖使用二氧化碳雷射剝除cladding後，利用本生燈加熱拉伸，使光纖錐化，腰徑越細的錐形光纖對環境折射率變化越敏感。在表面修飾球狀金奈米粒子。隨著外界環境的折射率變化，光纖的強度變化會較未修飾金奈米粒子時顯著，製作不同粗細及長度的光纖感測器，希望讓感測器的參數與感測靈敏度達到最佳化。

關鍵字

漸逝波 ； 錐形光纖 ； 折射率 ； 金奈米粒子 ； 感測器 ； 定域化表面電漿共振

並列摘要

In this thesis, fabrication of a multimode tapered fiber is presented. The coating and cladding of the fiber was first removed by using the CO2 laser. Afterward, while heating the uncladded fiber with the Bunsen burner, a tapered fiber was made by pulling the fiber to a desired length by a translational stage. The ability of the fabricated tapered fiber to detect the refractive index (RI) of surrounding media is investigated. It is found that the RI sensitivity of this type of tapered fiber increased with the decreasing of waist diameter of the tapered fiber. Further modification of the tapered fiber with colloidal gold nanoparticles show that the RI sensitivity can be enhanced based on the mechanism of localized surface plasma resonance.

並列關鍵字

evanescent wave ； tapered fiber ； reflective index ； gold-nano-particle ； sensor ； localize surface plasmon resonance

參考文獻

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