Picosecond nonlinear optical response of a Cu:silica nanocluster composite

Abstract

We describe the picosecond nonlinear optical response of a metal–dielectric composite made by implanting Cu ions in fused silica. The implanted Cu ions aggregate during implantation to form nanometer-diameter clusters in a dense, thin (~150 nm) layer just beneath the surface of the substrate. The third-order susceptibility χ⁽³⁾ has an electronic component with a magnitude of the order of 10⁻⁸ esu and is enhanced for laser wavelengths near the surface plasmon resonance of the copper colloids.