- 學位論文
銀奈米粒子與多顆銀島之近場耦合對金屬增強螢光效益之影響
Near-field coupling of silver nanoparticle and silver islands on metal-enhanced fluorescence
摘要
本文研究多顆銀島的近場耦合效應，銀島與銀島結構的表面電漿子耦合使間隙區域的|E|提升，並在銀島的上方增加銀球來探討金屬螢光增益。本文利用多重中心展開法(MMP)來模擬位於間隙區域之近場耦合，分別分析不同的銀島數量之結構、平面波的入射角度、銀島排列組合、不同間隙的近場耦合效應，在透過銀球來探討銀球水平位置對金屬螢光增益之影響。 數值分析結果指出，增加銀島的數量，散射截面積效率在波長600 nm~750 nm時的模態越顯著，此模態即為銀島與銀島之間耦合效應的現象。當平面波由銀島群正上方入射時，銀島與銀島間環環相扣的耦合效應十分明顯。銀球的影響僅對激發率的強度大幅的提升，整體激發率的曲線分布還是由螢光分子位置以及多顆銀島為主導。
並列摘要
This thesis studies for the plasmon-enhanced local field around multiple adjacent silver islands (SIs). The coupling plasmonic effect of the SIs enhance the near electromagnetic (EM) field within the gap zone, and at the top of SIs to increase a silver nanoparticle (SNP) to investigate the metal enhanced fluorescence (MEF). Maxwell electromagnetic theory together with the multiple multipole method are used to compute the induced EM field of the gap zone. This thesis use quantitative research method to analyze the effects of plasmon-enhanced local field with amount of SIs, the incident angles of plane wave, permutation of SIs, and different gaps of SIs. Finally, this thesis researches the MEF by changing the SNP horizontal position. Numerical results show that an extra peak at wavelength 600 nm ~ 750 nm is observed in the scattering of the efficiency as the number of silver islands increase. This peak can be interpreted as coupling effect between silver islands. When a plane wave incident angle , the coupling chain effect of silver islands is strong. The effect of silver nanoparticle significantly improve the intensity of excitation rate, phenomenon of the excitation rate is led by the position of fluorescent molecule and the amount of silver islands.