Computational Multiscattering of Spherical Multilayered Gold Nanoshells

A generalized computational methodology is developed and applied to study multiscattering phenomena associated with an aggregate of multilayered nanoshells under excitation of a plane wave. The development is based on a combination of the vector addition theorem for spherical wave functions and the 4 efficient recursive procedure for multilayered nanoshells. Calculated results are compared well with spectral measurements for a Au@SiO2 nanodimer. They are also in qualitative agreement with laboratory observations. Resonance behavior of a Au@SiO2 nanoshell chain depends on the number of particles in the chain, the orientation of the chain, and the interparticle spacing. Strong localized field enhancement is observed in the gap between two adjacent particles, and intense Joule heating occurs in the portion of the metal shell where the field enhancement is weak. The coupled plasmonic resonance of a multilayered nanodimer is analyzed, and its application as a plasmon ruler is discussed.