Ultrafast core-to-core luminescence in BaF${}_2$-LaF${}_3$ single crystals

Abstract

This study investigates the mechanisms underlying ultrafast cross-luminescence observed in BaF${}_2$ crystals doped with LaF${}_3$. We identified an ultrafast luminescent component with a decay time of approximately 150 ps, which emerges under excitation energies exceeding 24 eV as a novel radiative recombination process between electrons in the 5p core band of Ba2+ and holes in the 5p core band of La${}^{3+}$. Ab initio calculations support this hypothesis, showing that the energy levels of the core bands facilitate such transitions. The findings indicate that BaF${}_2$-LaF${}_3$ scintillators hold significant promise for applications in time-of-flight tomography.

7 pages

References in corpus (1)

• Ultraviolet cross-luminescence in ternary chlorides of alkali and alkaline-earth metals