Universality of the Dynamic Characteristic Relationship of Electron Correlation in the Two-Photon Double Ionization Process of a Helium-Like SystemSupported by the National Natural Science Foundation of China (Grant Nos. 91850209, 11774129, and 11774411), and the National Key Research and Development Program of China (Grant Nos. 2019YFA0307700 and 2016YFA0401100).

Abstract

Universality of the dynamic characteristic relationship between the characteristic time t c and the two-electron Coulomb interaction energy of the ground state in the two-photon double ionization process is investigated via changing the parameters of the two-electron atomic system and the corresponding laser conditions. The numerical results show that the product keeps constant around 4.1 in the cases of changing the nucleus charge, the electron charge, the electron mass, and changing simultaneously the nucleus charge and the electron charge. These results demonstrate that the dynamic characteristic relationship in the two-photon double ionization process is universal. This work sheds more light on the dynamic characteristic relationship in ultrafast processes and may find its application in measurements of attosecond pulses.