OPTICAL NONLINEARITY ENHANCEMENT VIA GEOMETRIC ANISOTROPY

We investigate the effects of geometric anisotropy on the optical nonl inearity of metal nanocrystals in a dielectric host. BS invoking the e ffective medium approximation for anisotropic composite media, we calc ulate the spectral density as a function of volume fraction and anisot ropy. The results show that anisotropy not only changes the spectral f unction substantially and thereby has a pronounced effect on the nonli nearity, but also separates the absorption peak from the nonlinearity enhancement peak so that the figure of merit may be increased by order s of magnitude. We propose the use of electrorheological effect (e.g., during annealing) to realize these gains in optical nonlinearity.