Berlin 2001 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

MO: Molekülphysik

MO 1: Posters Monday: Clusters, Fullerenes and Nanotubes

MO 1.19: Poster

Montag, 2. April 2001, 12:30–15:00, AT3

Ionization of sodium clusters by strong femtosecond light pulses — •Larisa Kurkina — Institute of Thermophysics SB RAS, Novosibirsk 630090, Russia

The ionization spectra of sodium clusters containing 8, 20, 40, and 58 atoms under strong laser pulses with peak intensities of 10¹² − 10¹⁴ W/cm², time duration of 10 - 200 fs, and photon energies of 1.0 - 3.5 eV are calculated within the framework of the density-functional theory by direct numerical solution of the time-dependent Kohn-Sham equation applied to a jellium model. The strongest electron escape is found in the region between 2 and 3 eV. A heavy dependence of the electron response on cluster size, intensity and time duration of light pulses are obtained. The electron emission markedly decreases when a light intensity is reduced (even though the pulse energy is conserved through the respective increasing of pulse duration). The ionization spectra of different clusters under the same light pulses come close together if the spectra are normalized to cluster radii squared. A great enhancement of the kinetic energy of electrons keeping in the clusters is detected (that can involve the subsequent thermal electron emission).