Schütte B, Lahl J, Oelze T, Krikunova M, Vrakking M J J, Rouzée A
Max-Born-Institut, Max-Born-Strasse 2A, 12489 Berlin, Germany.
Department of Physics, Imperial College London, South Kensington Campus, SW7 2AZ London, United Kingdom.
Phys Rev Lett. 2015 Mar 27;114(12):123002. doi: 10.1103/PhysRevLett.114.123002. Epub 2015 Mar 24.
Electron emission as a result of the interaction of clusters with intense laser pulses is commonly understood in terms of direct and evaporative ionization processes. In contrast, we provide evidence here of an important role played by autoionization in intense field ionization of molecular oxygen clusters. Superexcited states are populated during the cluster expansion, and their autoionization is observed on a ns time scale. Decay processes on fs to ps time scales are obscured by energy exchange of the emitted electrons with the environment.
团簇与强激光脉冲相互作用产生的电子发射通常根据直接电离和蒸发电离过程来理解。相比之下，我们在此提供证据表明自电离在分子氧团簇的强场电离中发挥了重要作用。在团簇膨胀过程中形成了超激发态，并在纳秒时间尺度上观察到了它们的自电离。飞秒到皮秒时间尺度上的衰变过程被发射电子与环境的能量交换所掩盖。
