Quantum effects on the multiphoton dissociation of a diatomic molecule

The chaotic vibrations of a diatomic molecule in an intense monochromatic electromagnetic field are classically and quantum mechanically analyzed. It is shown that the driven motion in a Morse potential is accurately described by a return map--the Morse map, whose derivation in various degrees of approximation is presented in detail. The quantization of the map is also considered. The quantized map, though acting on states in the energy range of bound states only, is shown to be influenced by intermediate states above the dissociation threshold, i.e., effects of the continuum are incorporated. Detailed numerical results are presented and various localization mechanisms are discussed and compared.