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Ultrafast core-to-core luminescence in BaF2 - LaF3 single crystals
Roman Shendrik1, Evgeny Radzhabov1, Alexandra Myasnikova1
1Vinogradov Institute of Geochemistry, SB RAS, Favorskii St. 1a, Irkutsk, 664033, Russia.
Scientific Reports
|July 22, 2025
Summary
Barium fluoride (BaF2) crystals doped with lanthanum fluoride (LaF3) exhibit ultrafast cross-luminescence. This novel process involves core-band electron-hole recombination, promising for advanced detection applications.
Area of Science:
- Solid State Physics
- Materials Science
- Quantum Electronics
Background:
- Ultrafast cross-luminescence in BaF2 crystals is a phenomenon requiring detailed mechanistic understanding.
- Doping with LaF3 introduces unique properties to BaF2 scintillators.
Purpose of the Study:
- To elucidate the underlying mechanisms of ultrafast cross-luminescence in BaF2:LaF3 crystals.
- To identify the specific electronic transitions responsible for the observed luminescence.
Main Methods:
- Experimental investigation of luminescence properties under high-energy excitation (>24 eV).
- Ab initio theoretical calculations to model electronic band structures and transitions.
Main Results:
- Identification of an ultrafast luminescent component with a decay time of ~150 ps.
- Discovery of a novel radiative recombination process between Ba2+ 5p core band electrons and La3+ 5p core band holes.
- Theoretical calculations confirm the feasibility of these core-band transitions.
Conclusions:
- The BaF2-LaF3 system exhibits a unique ultrafast cross-luminescence mechanism.
- This phenomenon is attributed to core-band electron-hole recombination.
- BaF2-LaF3 scintillators are promising for ultrafast process detection in high-energy physics and medical imaging.
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