Abstract

Composite materials formed by metallic nanocrystals (NCs) embedded in transparent hosts exhibit an enhanced third order non-linear response that might provide the physical base for the development of all optical switching devices. The non-linear optical response of these materials is determined by dielectric and quantum confinement effects caused by the small dimensions of the NCs when compared to both the wavelength of the incident light and the mean free path of the electrons in the bulk material. Moreover, not only the control of the size, but also that of the shape and size distribution of the NCs are critical issues for the production of composites having the required structural and optical quality for the development of real devices. Pulsed laser deposition has been recently demonstrated to provide a valuable route for the synthesis of such materials with an excellent control of their structural properties and high non-linear response. This communication is aimed at analysing the influence of the morphology (size and shape) of metal NCs on their third order non-linear optical response (χ³).

© 2000 IEEE