ID:
439196.0,
MPI für Kernphysik / Physics with Ultrashort Laser Pulses |
Einfluß der Träger-Einhüllenden-Phase auf die Wechselwirkung ultrakurzer Laserpuls mit Molekülen |
Authors: | Kremer, Manuel |
Referees: | Moshammer, Robert; Wolf, Andreas |
Language: | German |
Date of Approval (YYYY-MM-DD): | 2009-11-04 |
Name of University: | Ruprecht-Karls Universität |
Place of University: | Heidelberg |
Physical Description (e.g. Total Number of Pages): | IV, 120 S. : Ill., graph. Darst. |
Audience: | Experts Only |
Abstract / Description: | Englisch: In this work the fragmentation of $H_2$ molecules in ultra-short (6fs), intense laser pulses with stabilized carrier-envelope-phase (CEP) has been investigated experimentally. The use of a reaction microscope for the detection of all created charged particles allowed a separation of different reaction channels as well as a coincident detection of electrons and ions. For the first time a theoretical predicted dependence of the proton emission direction from the CEP in the low-energy range of the dissociation channel was observed what is equivalent to a localization of the bound electron in the dissociating $H_2^+$ that is driven back and forth between the two nuclei by the laser field. The coincident detection of ions and electrons allowed it to investigate the role of the first ionization step ($H_2 rightarrow H_2^+$) and the laser induced coupling of the two ionic states $1ssigma_g$ and $2psigma_u$ for the dissociation asymmetry. Wave-packet propagation simulations underlined the importance of the creation of a coherent wave packet in the $H_2^+$-potential for the achievable asymmetry. In addition to investigations of the prototype molecule $H_2$ the control of fragmentation processes in multi-electron-systems by varying the CEP was demonstrated on carbon monoxide what points towards future control of chemical reactions. |
Document Type: | PhD-Thesis |
Affiliations: | MPI für Kernphysik/Group of J. Ullrich/Strong-Fields Physics (R. Moshammer)
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