利用数值求解含时薛定谔方程的方法研究了氦原子在超短红外激光脉冲和极紫外激光场作用下的双电离过程。在此过程中,一个电子首先被极紫外激光场电离,然后氦离子既可以被接下来的红光激光场直接隧穿电离,也可以被红外激光场驱动下的电子再散射而发生非次序双电离。这两种双电离通道的干涉可以产生新颖的电子关联动量谱分布。当驱动红外激光脉冲为周期量级时,再散射导致的双电离的两个电子的运动方向可以相同,也可以相反。

The double ionization of helium in the combined extreme ultraviolet (EUV) pulse and extremely short mid-infrared (MIR) laser pulse is studied by numerically simulating the time-dependent Schr dinger equation. In this process, the EUV pulse kicks off one electron, and then the produced He ⁺ is either sequentially tunneling ionized by the remaining MIR pulse, or nonsequentially impact ionized by the rescattering electron driven by the MIR laser pulse. The interference of the coexisted sequential and nonsequential double ionization events produces an unexplored electron-electron joint momentum distribution. The two electrons released via rescattering may propagate along the same direction and also propagate along the opposite directions when such an extremely short laser pulse is implemented.