Design Of Nano-antenna With New Structure For Fluorescence Enhancement

The orientation of fluorophore is usually hard to control,and it's difficult to enhance the fluorescence to the same extent for different orientationsusing traditional nanoantennas.This thesisproposes a highly-symmetrical cross nanoantenna,theoretically analyzesitscapability of fluorescence enhancement for differently oriented fluorophore.The results show that compared with the traditional line nanoantenna,the cross nanoantenna couldgenerate stable enhancement for differently oriented fluorophore,as well as preserve their polarization properties.Further,we modify the pure metal cross nanoantenna by covering a dielectric shell on it,forming a core-shell structure whose excitation rate and quantum yield has been both improved,leading to the ultimate fluorescence enhancement more than double that of the pure metal cross nanoantnena.