Femtosecond subtreshold ionization of clusters
The separation of electronic and vibrational times scales opens the possibility that electronic matter in a highly excited incoherent state coexist for a short time with cold vibrations. During this short time, of a picosecond or less, the hot electrons can emit thermal electrons with extremely high temperatures from clusters and fullerenes.
Experiments on fullerenes and endoheral fullerenes with femtosecond laser pulses at deep sub-threshold photon energies will be presented. In the experiments electron energy distributions and ionic photo-fragmentation have been measured and analyzed in terms of this hot electron model.