Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA.
Phys Rev Lett. 2010 Dec 31;105(26):263003. doi: 10.1103/PhysRevLett.105.263003. Epub 2010 Dec 27.
Helium atoms in the presence of extreme ultraviolet light pulses can lose electrons through direct photoionization or through two-electron excitation followed by autoionization. Here we demonstrate that, by combining attosecond extreme ultraviolet pulses with near infrared femtosecond lasers, electron dynamics in helium autoionization can be not only monitored but also controlled. Furthermore, the interference between the two ionization channels was modified by the intense near infrared laser pulse. To the best of our knowledge, this is the first time that double excitation and autoionization were studied experimentally by using isolated attosecond pulses.
氦原子在极端紫外光脉冲的存在下可以通过直接光电离或通过双电子激发后自电离失去电子。在这里，我们证明通过将阿秒极端紫外脉冲与近红外飞秒激光相结合，不仅可以监测氦原子自电离中的电子动力学，还可以控制其电子动力学。此外，强近红外激光脉冲还改变了两个电离通道之间的干涉。据我们所知，这是首次使用孤立的阿秒脉冲实验研究双激发和自电离。
