Li Baoqin, Yang Xie, Ren Xianghe, Zhang Jingtao
Opt Express. 2019 Oct 28;27(22):32700-32708. doi: 10.1364/OE.27.032700.
We report that the nonsequential double ionization (NSDI) probability of an O target can be enhanced greatly in a counter-rotating circularly polarized two-color driving field. The field is composed of a fundamental frequency and its third harmonic, and the combined electric field traces out a four-leaf-clover pattern. The electron ionized by such a field has more chances to collide with the valence electrons in the O molecule, which significantly enhances the NSDI probability. This effect is more evident in low-intensity fields. We also find that the enhancement appears in a broad range of the field ratio of two colors and that both the NSDI yield and the underlying electronic behavior varies notably with the field ratio.
我们报道，在反向旋转的圆偏振双色驱动场中，氧（O）靶的非顺序双电离（NSDI）概率可以大大提高。该场由基频及其三次谐波组成，合成电场描绘出四叶苜蓿图案。被这样一个场电离的电子有更多机会与氧（O）分子中的价电子碰撞，这显著提高了NSDI概率。这种效应在低强度场中更为明显。我们还发现，在很宽的双色场强比范围内都出现了增强现象，并且NSDI产率和潜在的电子行为都随场强比显著变化。
