Abstract
Expressions for the enhancement of the far-field scattering cross section of a luminescent or Raman-active compound contained within a multilayered nanosphere are derived, where the active compound resides between an outer metallic shell and a metallic core. The quasi-static approximation is assumed for silver and gold particles using a Lorentz-Drude model of the dielectric function. An attempt has also been made to account for the effect of electron scattering from the boundaries of the shell on the enhancement calculation.