Plasmon−exciton couplings in Al−CuCl nanoshells and the effects of oxidation

The plasmon-exciton couplings in the Al-CuCl nanoshells have been investigated by using the Mie scattering theory. It is found that the bright dipole mode of the Al nanosphere can couple well with the exciton mode of the outer CuCl shell in the UV region by changing the geometry. The strong plasmon-exciton couplings in the Al-CuCl nanoshell lead to two hybrid plexcitonic modes and hence the Rabi splitting. We study the dispersion curves of the plexcitonic modes of the Al-CuCl nanoshells and obtain the splitting energy of about 135 meV. Furthermore, the influences of the metal oxide on the plasmon-exciton couplings in the Al-CuCl nanoshells have been studied. It is found that the Rabi splitting energy will shrink with the oxide.