We determined the third-order susceptibility [χ(3)] of a thin composite film formed by silver nanoclusters embedded in soda-lime glass. Ag aggregation was promoted by irradiating an Ag-Na ion-exchanged glass with an N+beam. [χ(3)] dispersion was measured by phase-mismatched degenerate four-wave mixing in the 380-470 nm spectral range, with 0.5 ps laser pulse duration. Close to the surface plasmon resonance of Ag metallic clusters, theχ(3)amplitude exceeds by a factor of 104the value of substrate glass. We also measured a phase of 83° and a dynamics characterized by ∼ 30, 3 and 0.9 ps decay times, ascribed to hot-electrons-lattice thermalization in the clusters, followed by thermal diffusion toward the matrix and relaxation of the whole system to the starting temperature.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
Faccio, D., Di Trapani, P., Borsella, E., Gonella, F., Mazzoldi, P., & Malvezzi, A. M. (1998). Measurement of the third-order nonlinear susceptibility of Ag nanoparticles in glass in a wide spectral range. Europhysics Letters, 43(2), 213 - 218. https://doi.org/10.1209/epl/i1998-00342-y