Düsseldorf 2007 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MO: Fachverband Molekülphysik
MO 61: Quantum Control I
MO 61.1: Vortrag
Freitag, 23. März 2007, 10:30–10:45, 6F
Excitation of C60 with Temporally Shaped Laser Pulses: Coherent Heating of Nuclear Motion — •Claus Peter Schulz, Ihar Shchatsinin, Tim Laarmann, Nickolai Zhavoronkov, and Ingolf Volker Hertel — Max Born Institute, Max-Born-Str. 2a, 12489 Berlin-Adlershof, Germany
Femtosecond laser pulses tailored with closed-loop, optimal control feedback were used to optimise the C2 evaporation from C60 [1]. A characteristic pulse sequence results in significant enhancement of the C50+ yield, a typical fragment of vibrationally hot C60, in comparison with the response to a single pulse of the same energy and overall width. The separation between subsequent pulses is close to the vibrational period of the radial symmetric ag(1) breathing mode. In a two-colour pump-probe experiment similar modulations were observed in the ion signal of multiply charges fragments. The observed period (80-127 fs) of this oscillation depends on the degree of ionisation and the deposited energy. Comparison with TDDFT calculations indicates that the shaped laser pulse excite giants oscillations in C60, which prevails for several cycles.
[1] T. Laarmann, I. Shchatsinin, A. Stalmashonak, M. Boyle, N. Zhavoronkov, J. Handt, R. Schmidt, C. P. Schulz, and I.V. Hertel, Physical Review Letters, in press (2006)