Field-free molecular alignment for probing collisional relaxation dynamics
Th. Vieillard, F. Chaussard, F. Billard, D. Sugny, O. Faucher, S. Ivanov, J.-M. Hartmann, C. Boulet, and B. Lavorel
Accepted
We report the experimental study of field-free molecular alignment in CO2 gas mixtures induced by intense femtosecond laser pulses in presence of collisional processes. We demonstrate that the alignment signals exhibit specific features due to non trivial collisional propensity rules that tend to preserve the orientation of the rotational angular momentum of the molecules. The analysis is performed with a quantum approach based on the modeling of rotational J and M dependent state-to-state transfer rates. The present work paves the way for strong-field spectroscopy of collisional dynamics.