Direct versus sequential double ionization of Mg with extreme-ultraviolet radiation

Area of Science:

• Atomic Physics
• Quantum Mechanics
• Computational Chemistry

Background:

• Multiphoton ionization is a fundamental process in atomic physics.
• Understanding electron correlation is crucial for describing atomic behavior.
• Previous studies have focused on simpler atomic systems.

Purpose of the Study:

• To perform the first ab initio calculation of multiphoton double ionization in an atom with a complex core (magnesium).
• To investigate the possibility of observing direct correlated double electron ejection.
• To assess the feasibility of using extreme-ultraviolet (XUV) radiation sources for such studies.

Main Methods:

• Ab initio calculations were employed to model the interaction of atomic magnesium with intense laser fields.
• The photoelectron energy spectrum was analyzed to identify signatures of double ionization.
• Simulations were performed considering the complex electronic structure of magnesium.

Main Results:

• The study successfully calculated the multiphoton double ionization of atomic magnesium.
• Direct correlated double electron ejection was found to be a significant process.
• The results indicate that the photoelectron energy spectrum contains distinct features corresponding to this ejection mechanism.

Conclusions:

• Ab initio calculations are a viable method for studying complex atomic ionization processes.
• Direct correlated double electron ejection in complex atoms can be experimentally observed.
• Upcoming extreme-ultraviolet radiation sources are suitable for investigating these phenomena.