Third-Order Nonlinear Optical Response of Layered Composites Materials Containing Gold Nanoparticles

Nonlinear third-order susceptibility $\chi _{\text {eff}}⁽³⁾$ of composites materials having alternated layers of dielectric and plasmonic nanostructures of gold nanoparticles was theoretically studied using the effective medium theory and the degenerate electron gas model. Real and imaginary parts of χeff(3) for the proposed composite material were calculated for the spectral region around the plasmon resonance of gold nanoparticles. The results reveal an enhanced nonlinear optical response compared with the obtained one for individual layers, as well as a reversal signal of $\chi _{\text {eff}}⁽³⁾$ for different volume fraction conditions.