Vibrational and Rotational Excitations of Diatomic Molecules by Chirped Laser Pulses

After a review of the “bucket dynamics” which classically accounts for the efficiency of chirped laser pulse excitation of the vibrations of a diatomic molecule, quantum mechanical results for the dissociation of diatomic molecules by a chirped pulse followed by a second laser pulse are presented. It is demonstrated that by using a second fixed‐frequency laser, dissociation without ionization is possible which each laser by itself would not suffice to dissociate the molecules. By using a second chirped laser pulse, additional excitation and dissociation of the molecule is observed. Similar to vibrational excitation, rotational excitation of a diatomic molecule can be accomplished by using a circularly polarized chirped laser pulse. Results of our quantum mechanical calculations show that coherent control of the rotational motion of a diatomic molecule is achievable.