Electron Dynamics of Atoms in Parallel Electric and Magnetic Fields

Through an analysis of the nearest neighbor level spacing statistics for atoms in parallel electric and magnetic fields, we investigate the evolution of the electron dynamics as electric field strength increases. In the 'inter-l mixing' predominant region, the electron shows complex dynamics while in the 'inter-n mixing' predominant region, its dynamics behaves in a relatively stable way and the characteristic quantity ξ shows a slight oscillation. Comparing the dynamics for hydrogen and barium, we find that the core effect makes the main contribution to the chaotic behavior in non-hydrogen atoms.