Chaloupka Jan L, Hickstein Daniel D
Department of Physics and Astronomy, University of Northern Colorado, Greeley, Colorado 80639, USA.
JILA-Department of Physics, University of Colorado and NIST, Boulder, Colorado 80309, USA.
Phys Rev Lett. 2016 Apr 8;116(14):143005. doi: 10.1103/PhysRevLett.116.143005. Epub 2016 Apr 7.
The double ionization of helium in bichromatic, circularly polarized intense laser fields is analyzed with a classical ensemble approach. It is found that counterrotating fields produce significant nonsequential double-ion yield and drive novel ionization dynamics. It is shown that distinct pathways to ionization can be modified by altering the relative intensities of the two colors, allowing for unique control of strong-field processes. Electrons are observed to return to the ion at different angles from the angle of ionization, opening new possibilities for probing electronic and molecular structure on the ultrafast time scale.
采用经典系综方法分析了双色圆偏振强激光场中氦的双电离过程。发现反向旋转场会产生显著的非顺序双电离产额，并驱动新的电离动力学。结果表明，通过改变两种颜色的相对强度，可以改变不同的电离途径，从而实现对强场过程的独特控制。观察到电子从电离角度以不同角度返回离子，这为在超快时间尺度上探测电子和分子结构开辟了新的可能性。
