Seminario | Dr. Piero Ferrari (Laboratory of Solid State Physics and Magnetism, K U Leuven, Belgium)

Correlations between the electronic structure and the radiative cooling of small metallic clusters in the gas phase

Abstract

Only during the last few years, experiments on small clusters in the gas phase have shown the relevance of radiation as a cooling mechanism in these small groups of atoms. Not only many clusters have been shown to radiate at surprisingly high rates, but also rates seem to correlate strongly with the electronic structure of the clusters. Since this is strongly determined by quantum confinement effects and valence electron delocalization, radiation proceeds in a remarkable size-dependent manner. The consequences of radiative cooling are various, ranging from a basic understanding on how electron correlations determine the emission of radiation on a small group of atoms, to the production of size-selected nanoparticles or even in astrophysics; isolated molecules in the interstellar medium need to cool down before condensing due to gravity and hence forming new planets and stars. In this talk, recent discoveries on the decay mechanisms of small clusters will be discussed, together with the many remaining questions open in the field and the efforts currently performed in order to answer them.