Eckart S, Richter M, Kunitski M, Hartung A, Rist J, Henrichs K, Schlott N, Kang H, Bauer T, Sann H, Schmidt L Ph H, Schöffler M, Jahnke T, Dörner R
Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China.
Phys Rev Lett. 2016 Sep 23;117(13):133202. doi: 10.1103/PhysRevLett.117.133202. Epub 2016 Sep 20.
We report on nonsequential double ionization of Ar by a laser pulse consisting of two counterrotating circularly polarized fields (390 and 780 nm). The double-ionization probability depends strongly on the relative intensity of the two fields and shows a kneelike structure as a function of intensity. We conclude that double ionization is driven by a beam of nearly monoenergetic recolliding electrons, which can be controlled in intensity and energy by the field parameters. The electron momentum distributions show the recolliding electron as well as a second electron which escapes from an intermediate excited state of Ar^{+}.
我们报告了用由两个反向旋转的圆偏振场（390和780纳米）组成的激光脉冲对氩进行非顺序双电离的情况。双电离概率强烈依赖于两个场的相对强度，并呈现出作为强度函数的膝状结构。我们得出结论，双电离是由一束几乎单能的再碰撞电子驱动的，其强度和能量可通过场参数进行控制。电子动量分布显示了再碰撞电子以及从Ar⁺的中间激发态逃逸的第二个电子。
