The Nonlinear Optical Response of Hashin-Shtrikman Geometric Composite Materials

The nonlinear optical response of composite materials consisting of metal grains with insulator shells at finite frequency is investigated. It is found that the surface plasmon peak is stronger and the position of surface plasmon peak is "red-shifted" with the shell being thinner. We also found that the nonlinear optical response is related to the shape of the particles and the dielectric property of the shells.