Size effects in the ultrafast electronic dynamics of metallic tin nanoparticles

Abstract

We report on femtosecond transient reflectivity measurements performed on metallic tin nanoparticles, embedded in an ${\mathrm{Al}}_{2}$${\mathrm{O}}_{3}$ matrix, with average radii in the range 20--60 \AA{}. It was observed that the time behavior of the transient reflectivity decays depends upon particle size. The results can be interpreted in terms of a size-dependent electron-surface interaction in the thermalization process and of a substantially size-independent electron-electron thermalization. \textcopyright{} 1996 The American Physical Society.