Quadratic electro-optic effects and electro-absorption process in multilayer nanoshells

The third-order nonlinear susceptibility is obtained as a function of wavelength for a multilayer nanoshell structure. Numerical calculations show that the nonlinear susceptibility of this structure depends on parameters such as the structure size, relaxation time and pump photon energy. The intensity and position of third-order nonlinear susceptibility peaks depend on shell thicknesses; smaller thicknesses have peak susceptibility at shorter wavelengths.