Restricted-space ab initio models for double ionization by strong laser pulses

Abstract

Double electron ionisation process occurs when an intense laser pulse interacts with atoms or molecules. Exact ab initio numerical simulation of such a situation is extremely computer resources demanding, thus often one is forced to apply reduced dimensionality models to get insight into the physics of the process. The performance of several algorithms for simulating double electron ionization by strong femtosecond laser pulses are studied. The obtained ionization yields and the momentum distributions of the released electrons are compared, and the effects of the model dimensionality on the ionization dynamics discussed. arXiv:1803.08364v2 [physics.atom-ph]

Double ionization of a three-electron atom: Spin correlation effects

“…restrict the electronic motion to one-dimensional tracks inclined at constant angle with respect to the polarization axis. In order to connect the three-and two-dimensional models, we need a compromise in the choice of tracks: in the two-electron case, the field axis lies in the plane spanned by the electrons [40][41][42][43][44]. In the three electron case, the planes spanned by two of the axes do not contain the field axis and maintain some angle to it.…”

Strong-field triple ionization of atoms with $p^3$ valence shell

“…taking into account all spatial dimensions for each electron, quantum calculations even for two electrons are * jakub.prauzner-bechcicki@uj.edu.pl still very rare [9][10][11][12][13]. Simplified quantum models with a reduced number of dimensions are often used to overcome the numerical difficulty [6,[14][15][16][17][18][19][20][21][22][23][24]. And in the case when three and more electrons are involved, classical or semi-classical calculations are dominant [25][26][27][28][29][30][31].…”

Strong-field triple ionisation of atoms with p 3 valence shell

“…To calculate ionisation yields we apply a space division method introduced in the seminal work treating DI of He [55]. This approach was commonly used in both classical and quantum-mechanical calculations [36,37,54,55]-compare figures 1(b) and (c). The full configuration space of the problem is divided into non-overlapping regions which fully cover the space.…”

“…taking into account all spatial dimensions for each electron, quantum calculations even for two electrons are still very rare [25][26][27][28][29]. Simplified quantum models with a reduced number of dimensions are often used to overcome the numerical difficulty [6,[30][31][32][33][34][35][36][37][38][39][40]. And in the case when three and more electrons are involved, classical or semi-classical calculations are often used [41][42][43][44][45][46][47] with the independent electron model [20] likely being applicable only at very high intensities.…”