Control of Quantum Dynamics by Laser Pulses: Adiabatic Floquet Theory
Résumé
We present in a self-contained way a set of theoretical tools that allow us to analyze the quantum dynamics of atoms and molecules driven by laser pulses and to determine pulse designs that lead to specific effects. In particular, we discuss processes to control the internal excitation of states, like electronic states or vibrational and rotational states of molecules. We describe the Floquet formalism, and we show how it can be used to establish the relation between the semiclassical model and a quantized representation that allows us to describe explicitely the exchange of photons. We also describe an approach to perturbation theory that is based on applying unitary transformations that reduce the size of the coupling terms. The main ideas of adiabatic dynamics, combined with the Floquet approach, are also discussed. We describe how the possible transfers of population by adiabatic passage are determined by the topology of the eigenenergy surgfaces defined by varying the parameters of the pulses. Finally, we describe a more elaborate application of the method to state selectivity by bichromatic pulses in two-and three-level systems.
Origine | Fichiers produits par l'(les) auteur(s) |
---|