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Updated: Mar 24, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Carrier-envelope phase dependence of the directional fragmentation and hydrogen migration in toluene in few-cycle
Hui Li, Nora G Kling, Benjamin Förg
1Max-Planck-Institut für Quantenoptik , Hans-Kopfermann-Str. 1, D-85748 Garching, Germany.
Abstract:
The dissociative ionization of toluene initiated by a few-cycle laser pulse as a function of the carrier envelope phase (CEP) is investigated using single-shot velocity map imaging. Several ionic fragments, CH3 (+), H2 (+), and H3 (+), originating from multiply charged toluene ions present a CEP-dependent directional emission. The formation of H2 (+) and H3 (+) involves breaking C-H bonds and forming new bonds between the hydrogen atoms within the transient structure of the multiply charged precursor. We observe appreciable intensity-dependent CEP-offsets. The experimental data are interpreted with a mechanism that involves laser-induced coupling of vibrational states, which has been found to play a role in the CEP-control of molecular processes in hydrocarbon molecules, and appears to be of general importance for such complex molecules.
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