Size-dependent photoabsorption and photoemission of small metal particles.

Abstract

The dynamical electronic response properties of small metal particles are calculated within the frame of the self-consistent spherical jellium model. The method used is the TDLDA (time-dependent local-density approximation) with the inclusion of exchange and correlation. In this way we obtain for the first time insight into the nonlocal electronic response properties at a strictly microscopic level. The size dependence of photoabsorption, photoemission, and of the static polarizability, is discussed in detail. The emergence of the collective volume mode (the volume plasmon) as a function of the numbers of electrons is shown here for the first time. Likewise, the size-dependent Landau damping of these modes is obtained in a quantitative fashion. Compared with the results of any non-self-consistent model, we conclude that only a self-consistent theory like the TDLDA (or an improvement of it) is able to account for all the complexity of the electronic response in small dimensions.