Influence of spherically anisotropic core on the optical properties of gold nanoshell

The optical properties of gold nanoshell with a core of spherically anisotropic material have been investigated by means of quasi-static theory. It is found with increasing the extent of anisotropy of the core that the surface plasmon resonance for the particle shows a red-shift and that the full width at half maximum (FWHM) of the plasmon resonance peak increases. The local electric field of the particle with anisotropic core is found to be enhanced compared to that with isotropic core. The larger enhancement of the local electric field for the particle is observed in the particle with smaller extent of anisotropy.