State-resolved scattering of anions with neutral molecules in combination with strong laser fields, studied with velocity map imaging

• Applicant: Professor Dr. Roland Wester
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2005 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 20517204

Quantum state manipulation of charge transfer in few-body systems is investigated with the goal to control the quantum dynamics in the intermediate collision continuum and thereby steer the outcome of the collision. The main focus lies on charge transfer in small prototype systems for ion-atom and ion-molecule collisions at low relative energies. The application of state-of-the-art laser manipulation and cooling techniques serves as a tool to provide collision partners at well-defined internal and motional states. Our experiments are focused towards two directions, represented by two complementary subprojects. In Subproject A, charge transfer and ionization of the two stable rubidium isotopes in a magneto-optical trap is investigated in a kinematically complete way using COLTRIMS. The target atoms interact either with bunches of rubidium ions extracted from a novel ultracold laser ion source, or with strong femtosecond laser pulses. The latter experiment aiming at multiple photoionisation of rubidium is performed in a collaboration with Teilprojekt E3. In Subproject B, charge transfer and quantum dynamics in reactive ion collisions with molecules which are aligned in a strong laser field are studied. The cold ions are extracted from a buffer-gas cooled RF trap, while the molecules are cooled in a supersonic jet expansion. Stereodynamical effects as well as direct coupling of the electromagnetic field to the collision dynamics in this laser-assisted collision is investigated.

• DFG Programme: Research Grants
• Major Instrumentation: Pulsed Dye laser with Frequency Doubling Stage
• Instrumentation Group: 5720 Farbstoff-Laser
• Participating Person: Professor Dr. Matthias Weidemüller