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Updated: May 27, 2026
11:30
Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
Prominent higher-order contributions to electronic recombination
C Beilmann1, P H Mokler, S Bernitt
1Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.
Physical Review Letters
|November 24, 2011
Summary
Higher-order electronic recombination in highly charged ions like Argon shows unexpected strength as atomic number decreases. Second-order processes significantly exceed first-order recombination, confirmed by advanced calculations.
Area of Science:
- Atomic Physics
- Quantum Chemistry
- Spectroscopy
Background:
- Highly charged ions (HCIs) are crucial in astrophysics and fusion research.
- Intershell electronic recombination is a key process influencing HCI behavior.
- Previous studies focused primarily on first-order recombination.
Purpose of the Study:
- Investigate higher-order (HO) electronic recombination in HCIs.
- Quantify the contribution of HO recombination to total recombination rates.
- Explore the dependence of HO resonance strengths on atomic number (Z).
Main Methods:
- Experimental measurement of intershell HO electronic recombination.
- Resonant capture of free electrons by highly charged ions (Ar, Fe, Kr).
- Multiconfiguration Dirac-Fock (MCDF) calculations.
Main Results:
- Observed significant intershell HO electronic recombination in Ar, Fe, and Kr ions.
- Discovered unexpected strong dependence of HO resonance strengths on Z (∝Z(-4)).
- Found 2nd-order recombination to be dominant over 1st-order in Argon ions.
Conclusions:
- HO electronic recombination is a significant, previously underestimated, process in HCIs.
- The Z-dependence of HO recombination impacts modeling in various fields.
- MCDF calculations validate experimental findings and reveal importance of neglected pathways.
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