Open AccessAverage enhancement factor of molecules-doped coreshell (Ag@SiO_2) on fluorescence
Author(s) -
Jiunn-Woei Liaw,
Chuan-Li Liu,
Wei-Min Tu,
Chieh-Sheng Sun,
MaoKuen Kuo
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.012788
Subject(s) - doping , radius , fluorescence , optics , excited state , molecule , dipole , materials science , shell (structure) , atomic physics , molecular physics , physics , laser , analytical chemistry (journal) , optoelectronics , chemistry , computer security , quantum mechanics , chromatography , computer science , composite material
Average enhancement factor (AEF) of a coreshell (Ag@SiO(2)) on the fluorescence of molecules doped within the silica shell is proposed and studied to estimate the overall performance of a large number of coreshells. Using Mie theory and dyadic Green's functions, the enhancement factor (EF) of a coreshell is first calculated for any arbitrarily oriented and located electric dipole embedded in the shell. AEF is then obtained by averaging the individual EF over all possible orientations and positions of the electric dipoles. AEF of a FITC-doped coreshell (radius of Ag core: 25 nm, thickness of shell: 15 nm) irradiated by a laser of 488 nm for FITC's emission at 518 nm is 2.406. It is much smaller than the maximum EF (30.114) of a coreshell containing a single molecule with a radial orientation at its optimal position. For Alexa 430-doped coreshell excited at 428 nm, AEF is 12.34 at the emission of 538 nm.