a QuantumMechanical Study of AtomDiatom Collisions in a Laser Field.
Abstract
A quantummechanical formalism, in both space fixed (SF) and bodyfixed (BF) coordinate systems, is developed for describing an Sstate structureless atom (A) colliding with a Sigmastate vibrating rotor diatomic molecule (BC) in the presence of a laser field. The additional Hamiltonians H _{rad} and H_{int }, which describe the laser field and its interaction with the atomdiatom collision system, have been added to the fieldfree Hamiltonian H_0. And the collision problem can be solved by this extended Hamiltonian. The laser field Hamiltonian is represented by the number state representation. The interaction Hamiltonian is expressed by vecmu_{BC} cdot vec{cal E}, where vecmu_ {BC} is the dipole moment of the diatomic molecule BC, and vec{cal E} is the electric field strength of the laser field. Since the fieldfree total angular momentum J is coupling with the laser field, J and its zaxis projection M are no longer conserved. To facilitate the collision problem, the laser field is restricted to a single mode, and its interaction with the collision only involves dipole allowed transitions in which a single photon is absorbed or emitted. For convenience, the coupled channel equations are solved by the real boundary conditions instead of the complex boundary conditions. On applying the real boundary conditions, we obtain the Kmatrix, which is related to the Smatrix by S = (I + iK)(I  iK)^{ 1}. A model calculation is discussed for the Ar + CO collision system in a laser intensity of 10 ^9 W/cm^2.
 Publication:

Ph.D. Thesis
 Pub Date:
 1989
 Bibcode:
 1989PhDT.......150C
 Keywords:

 Physics: Molecular