Exciton interaction with Ce3+ and Ce4+ ions in (LuGd)3(Ga,Al)5O12 ceramics

Scintillators based on Ce-doped garnets are regularly co-doped with Mg2+ or Ca2+ to form Ce ions in 4+ state and reduce undesired afterglow. However overly high Ce4+ concentration leads to poor light yield performance. In order to understand the reason for variation in luminescence efficiency of Ce3+- and Ce4+-doped garnets we investigate the differences in energy conversion processes in complex LuGd2Ga3Al2O12:Ce3+/Ce4+ ceramics by means of VUV synchrotron irradiation. At first we have established via transmission spectroscopy and X-ray absorption spectroscopy that LuGd2Ga3Al2O12:Ce, Mg sample contains cerium in the 4+ state only. Then we show with VUV spectroscopy efficient interaction of excitons with Gd3+ and Ce3+, and lack of exciton absorption edge in LuGd2Ga3Al2O12:Ce4+ excitation spectrum. Instead, Ce4+ exhibits charge-transfer absorption band in the range of exciton emission. We suggest that when Ce4+ concentration becomes too high, the exciton → Gd3+ → Ce3+ energy transfer path is hindered. It leads to high intensity of Gd3+ luminescence in Lu1Gd2Ga3Al2O12:Ce, Mg ceramics, but lowered Ce3+ X-ray excited luminescence. Fine balance between 3+ and 4+ Ce concentrations is necessary to achieve the best performance of garnet scintillators.

Venevtsev, IvanSt. Petersburg State Polytechnical University (författare)
Chernenko, KirillLund University,Lunds universitet,MAX IV-laboratoriet,MAX IV Laboratory(Swepub:lu)ki7073ch (författare)
Pankratov, VladimirLund University,Lunds universitet,MAX IV-laboratoriet,MAX IV Laboratory,University of Latvia(Swepub:lu)vl7622pa (författare)
Klementiev, KonstantinLund University,Lunds universitet,MAX IV-laboratoriet,MAX IV Laboratory(Swepub:lu)maxl-kkv (författare)
van Swieten, ThomasUtrecht University (författare)
van Bunningen, Arnoldus J.Utrecht University (författare)
Vrubel, IvanSkolkovo Institute of Science and Technology (författare)
Shendrik, RomanA. P. Vinogradov Institute of Geochemistry of the Siberian Branch of the RAS (författare)
Ronda, CeesPhilips Research (författare)
Rodnyi, PiotrSt. Petersburg State Polytechnical University (författare)
Meijerink, AndriesUtrecht University (författare)
Delft University of TechnologySt. Petersburg State Polytechnical University (creator_code:org_t)

Av författaren/redakt...: Khanin, Vasilii; Venevtsev, Ivan; Chernenko, Kiril ...; Pankratov, Vladi ...; Klementiev, Kons ...; van Swieten, Tho ...; visa fler...; van Bunningen, A ...; Vrubel, Ivan; Shendrik, Roman; Ronda, Cees; Rodnyi, Piotr; Meijerink, Andri ...; visa färre...

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.