Effect of a dielectric coating on quenching in a molecule-nanosphere system

We investigate the effect a dielectric coating has on the energy transfer between a molecule and a silver nanosphere. For a fixed wavelength excitation resonant with the bare nanoparticle, increasing the shell thickness increases the non-radiative decay rate and decreases the radiative decay rate, which decreases the total efficiency of the emission process. The excitation wavelength can be tuned to improve the efficiency for coated nanoparticles, leading to values that are comparable to bare nanoparticles. As such, dielectric coatings are able to effectively limit quenching without sacrificing efficiency.