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

研究了少体系统中电荷转移的量子态操纵，目的是控制中间碰撞连续体中的量子动力学，从而控制碰撞的结果。主要的焦点在于在低相对能量下离子-原子和离子-分子碰撞的小型原型系统中的电荷转移。最先进的激光操作和冷却技术的应用作为一种工具，以提供明确定义的内部和运动状态的碰撞伙伴。我们的实验集中在两个方向，由两个互补的子项目代表。在子项目A中，利用COLTRIMS对磁光阱中两种稳定铷同位素的电荷转移和电离进行了运动学完整的研究。靶原子与从新型超冷激光离子源中提取的铷离子束或强飞秒激光脉冲相互作用。后一个实验的目标是铷的多重光电离，是与Teilprojekt E3合作进行的。在子项目B中，研究了强激光场中反应离子与定向分子碰撞的电荷转移和量子动力学。冷离子从缓冲气体冷却的RF阱中提取，而分子在超音速射流膨胀中冷却。研究了激光辅助碰撞中的立体动力学效应以及电磁场与碰撞动力学的直接耦合。

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.