摘要

We present a theoretical study on plasmonic enhancement of molecular fluorescence near a nanocomposite, Ag nanoshell (Ag-NS) coated by a gain medium of molecule-doped SiO2 layer. We use an average enhancement factor (AEF), which considers contributions from all possible orientations and locations of molecules in the silica layer to estimate the overall performance of Ag-NS@SiO2 at specific excitation and emission wavelengths. Our results on the AEF reveal that Ag-NS@SiO2 is a dual-band enhancer on the spontaneous emission of the gain medium; one is a narrowband in a shorter wavelength regime (quadrupole mode) and the other is a broadband in a longer wavelength regime (dipole mode). These two bands are tunable by adjusting the core size and the thickness of the Ag shell. Due to this merit, Ag-NS@SiO2 has great potentials to enhance Forster resonance energy transfer between a donor and a corresponding acceptor with large Stokes shifts.

  • 出版日期2011-12
  • 单位长春大学