Single crystalline film scintillators based on Ce- and Pr-doped aluminium garnets

Abstract

Luminescence and scintillation properties of single crystalline films (SCF) of Ce-and Pr-doped Y 3 Al 5 O 12 (YAG) and Lu 3 Al 5 O 12 (LuAG) garnets were analysed and compared with their bulk single crystal (SC) analogues. It was shown that the main peculiarities of luminescent properties of Ce-and Pr-doped YAG and LuAG SCF are due to the absence of Y Al and Lu Al antisite defects (AD) and to the extremely low concentration of vacancy-type defects in SCF with respect to SC. In SCF the absence of the AD-related traps results in faster energy transfer to the emission centres and accelerated scintillation response.

Novel UV-emitting single crystalline film phosphors grown by LPE method

“…SCF of garnets and perovskites is the strong quenching influence of the Pb 2þ flux impurity. From the results presented in Table 1, we conclude that significantly larger influence of Pb 2þ ions on the UV emission of Pr 3þ ions takes place in (Y,Lu)AG:Pr and (Y,Lu)AP:Pr SCFs in comparison with the influence of such impurity on the Ce 3þ emission in the visible range in SCF of Ce-doped garnets (Zorenko, et al, 2007a). The mechanism of the Pb 2þ / Pr 3þ energy transfer in Pr-doped SCF of garnets is considered by Gorbenko et al, 2009.…”

“…Shift of the emission spectra of SCF scintillators into the UV range with respect to recently developed SCFs of Ce 3þ -doped Y 3 Al 5 O 12 (YAG) and Lu 3 Al 5 O 12 (LuAG) garnets, emitting in the visible range (Zorenko, et al, 2007a), in principle, can result in the faster emission decay, larger light yield (LY) and higher energy resolution. Namely, we try to extend the class of novel UV-emitting SCF scintillators with the Ce-doped YAlO 3 (YAP) and LuAlO 3 (LuAP) perovskites and Pr 3þ -doped garnets and perovskites.…”

Time-resolved luminescent spectroscopy of YAG:Ce single crystal and single crystalline films

“…Recently the existence of these type centers in LuAG:Ce SC was confirmed by ESR (Laguta et al, 2007). Such centers can be responsible for the main TSL peak at 90 and 150 K in YAG:Ce and LuAG:Ce SC (Nikl et al, 2005) and large content (up to 75% in LuAG:Ce SC) of slow components in the Ce 3þ emission decay in these scintillators (Zorenko et al, 2007b). Contrary to YAG:Ce SC, due to the low (w1000 C) temperature of growth by liquid phase epitaxy (LPE) method from melt-solution, the YAG:Ce single crystalline film (SCF) scintillators are free from AD (Zorenko et al, 2007a,b).…”

“…Due to comparable concentration of both Ce 3þ ions and AD (up to 0.2 at. %), formation of the Ce-AD coupled centers can occur in (Y,Lu)AG:Ce SC (Zorenko et al, 2007b). Recently the existence of these type centers in LuAG:Ce SC was confirmed by ESR (Laguta et al, 2007).…”

“…Contrary to YAG:Ce SC, due to the low (w1000 C) temperature of growth by liquid phase epitaxy (LPE) method from melt-solution, the YAG:Ce single crystalline film (SCF) scintillators are free from AD (Zorenko et al, 2007a,b). The YAG:Ce SCF in comparison with SC analogues are characterized by faster decay of Ce 3þ emission under high-energy excitation, substantially less content of slow emission components and higher energy resolution due to absence of Y Al AD and low concentration of vacancies as emission and trapping centers (Zorenko et al, 2007b;Prusa et al, 2008).…”