The Resonance Scattering Quantum Yield with Modulated Structure of the Dielectric-Metal Multilayer Nanoshells

摘要

The resonance light scattering and scattering quantum yield (SQY) of Ag-Si-Ag multi-nanoshells (ASAMN) have been investigated in dipole approximation. The results show that the SQY at resonance wavelength of ASAMN can be enhanced to obtain an intense light scattering with high efficiency meanwhile, when the volume ratio fraction of silver to the multi-shells increases with the radius of inner silver sphere increasing or the inner radius of outer silver shell decreasing. By modulating the geometrical structure of the ASAMN, the frequency bands of the maximum SQY can be tuned in the visible and near-infrared regions. The physical mechanism has been illustrated by using the effective medium theory. It has been found that the effective dielectric constant plays an important role to affect the SQY in metal-dielectric core—shell nanostructures.