Optical second harmonic generation from plasmonic nanoshells using the nonlocal hydrodynamic model

In this paper, we investigate the linear and nonlinear optical response of spherical plasmonic nanoshells within the nonlocal hydrodynamical model for conduction electrons. The optical absorption and surface second-harmonic generation (SHG) associated with metallic core-shell nanoparticles is studied on the basis of the hydrodynamic Drude model. The influence of nonlocality on the optical SHG is investigated. We show that nonlocal effects can be applied to boost SHG from plasmonic nanoshells. It is found that the surface SHG radiation from the surface of nanoshells can be achieved by symmetry-breaking and is sensitive to nonlocality of the electron response. It is also shown that nonlocal effects lead to enhancement and shift of the resonant wavelengths of the optical absorption and SHG in metal nanoshells. Keywords: Optical absorption, Second harmonic generation, plasmonic nanoshell, nonlocal effects. •We investigate the optical absorption and SHG form plasmonic nanoparticles by using the nonlocal hydrodynamic model.•The optical absorption and harmonic generation regime can be controlled by choosing proper the size and composition of metal nanoparticle.•It is demonstrated that optical nonlinearities at nanoscale can be significantly affected by the nonlocal effects.