Abstract
We apply a time-dependent perturbation theory based on unitary transformations combined with averaging techniques, on molecular orientation dynamics by ultrashort pulses. We test the validity and the accuracy of this approach on LiCl described within a rigid-rotor model and find that it is more accurate than other approximations. Furthermore, it is shown that a noticeable orientation can be achieved for experimentally standard short laser pulses of zero time average. In this case, we determine the dynamically relevant parameters by using the perturbative propagator, which is derived from this scheme, and we investigate the temperature effects on molecular dynamics.
- Received 4 August 2003
DOI:https://doi.org/10.1103/PhysRevA.69.043407
©2004 American Physical Society