on the plasmonic properties of ag@sio2@graphene core-shell nanostructures

This work reports on a study regarding the plasmonic properties of the ag@sio2@graphene core-shell nanostructures, in the wavelength range of 0.3–2 μ m. spherical and ellipsoidal geometries of the core-shell structure are proposed. the extinction efficiency is numerically simulated with several parameters being varied, including the chemical potential of the graphene shell, the radius of the silver spherical core, and the background materials of air and water, as well as the geometry of the ellipsoids. two peaks are revealed in the extinction efficiency curve, which are attributed to the plasmonic resonance effect of the silver core and to that associated with the graphene shell, respectively. the results demonstrate that the plasmonic resonance wavelength of the peak that is induced in the graphene shell can be tuned in the wavelength range studied, by changing the value of the chemical potential. based on the plasmonic characteristics revealed in this study, it is suggested that the core-shell structure of ag@sio2@graphene be implemented in future designs of practical plasmonic devices.