奈米粒子表面電漿之研究與應用

本論文利用三維有限元素法研究週期式排列之實心奈米銀珠棒與厚度9 nm銀珠棒填入不同介電常數時之表面電漿模態。我們所提出的銀珠棒填入不同介電常數之結構是一個重要的電漿奈米金屬粒子，可以結合奈米尺度下金屬殼與介質柱中所填入不同電介質所引起的獨特光學性質。我們在論文中針對穿透率與吸收率頻譜、不同的填入介質、各分量電場、電場總場、電荷密度分布、電將模態等與入射光間之交互作用加以分析比較，模擬結果顯示厚度9nm的銀珠棒填入不同介電材料時會有明顯的表面電漿共振模態產生，並顯示出3種不同的共振模態，而此現象是在其他同樣體積下實心結構的奈米銀粒子上所看不到的。

關鍵字

有限元素法；表面電漿；奈米粒子

並列摘要

In this thesis, the filling media effects of surface plasmon resonance (SPR) modes for the periodic array of 9 nm Ag-shell nanobead with filling different dielectric media and their solid counterparts are numerically investigated and compared by means of finite element method with three-dimensional calculations. The investigated Ag-shell nanobead array is an important novel geometry for plasmonic metal nanoparticles (MNPs), combining the highly attractive nanoscale optical properties of both metallic nanoshell and cylindrical pore filled with a dielectric. Numerical results for SPR modes corresponding to the effects of different illumination wavelengths, transmission and absorption spectra, pore-dielectric, electric field components and total field distribution, charge density distribution, and the model of the induced local field or an applied field of the Ag-shell nanobead array are reported as well. It can be found that the proposed Ag-shell nanobead array with cylindrical pore filled with a dielectric in the Ag-shell nanobead exhibit tunable three SPR modes corresponding to the bonding and anti-bonding modes, that are not observed for their solid counterparts.