Expression of Concern: Field enhancement by uniform nanoshell dimers in the quasistatic regime

Nanoshell dimers are composed of two nanoshells in close proximity of each other and have unique properties that arise from the interaction of the surface plasmon oscillations on the surface of the two nanoshells. The field enhancement, as well as the resonance wavelength, of a nanoshell depends on the nanoshell separation. In this paper, we study the resonance properties of plasmonic nanoshell dimers in the quasistatic regime. We solve Laplace's equation in spherical coordinates, using a change in coordinate systems to arrive at a solution for the scattered field. We study the dependence of the field enhancement and resonance wavelength on the dimer parameters, mainly the nanoshell separation.