TSL

Effect of Mg2+ ions co-doping on luminescence and defects formation processes in Gd3(Ga,Al)5O12:Ce single crystals

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V. Babin , P. Bohacek , L. Grigorjeva , M. Kucera , M. Nikl , S. Zazubovich , A. Zolotarjovs
Photo- and radioluminescence and thermally stimulated luminescence characteristics of Ce3+ – doped
and Ce3+, Mg2+ co-doped Gd3(Ga,Al)5O12 (GAGG) single crystals of similar composition are investigated in the 9-500 K temperature range. The Ce3+ – related luminescence spectra and the photoluminescence decay kinetics in these crystals are found to be similar. Under photoexcitation in the Ce3+ – and Gd3+ – related absorption bands, no prominent rise of the photoluminescence intensity in time is observed neither in GAGG:Ce,Mg nor in GAGG:Ce crystals. The afterglow is strongly reduced in GAGG:Ce,Mg as compared to GAGG:Ce, and the afterglow decay kinetics is much faster. Co-doping with Mg2+ results in a drastic decrease of the thermally stimulated luminescence (TSL) intensity in the whole investigated temperature range and in the appearance of a new complex Mg2+ – related TSL glow curve peak around 285 K. After irradiation in the Ce3+ – related 3.6 eV absorption band, the TSL intensity in GAGG:Ce,Mg is found to be comparable with that in the GAGG:Ce epitaxial film of similar composition. The Mg2+ – induced changes in the concentration, origin and structure of the crystal lattice defects and their influence on the scintillation characteristics of GAGG:Ce,Mg are discussed.

2017 gagg paper

Optical Materials 66 (2017) 48-58

DOI: 10.1016/j.optmat.2017.01.039

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Thermally stimulated luminescence of undoped and Ce3+-doped Gd2SiO5 and (Lu,Gd)2SiO5 single crystals

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V. Bondar, L. Grigorjeva, T. Kärner, O. Sidletskiy,
K. Smits, S. Zazubovich, A. Zolotarjovs

Thermally stimulated luminescence (TSL) characteristics (TSL glow curves and TSL
spectra) are investigated in the 4-520 K temperature range for the X-ray irradiated at 4 K, 8
K, or 80 K single crystals of gadolinium and lutetium-gadolinium oxyorthosilicates. The
nominally undoped Gd2SiO5 and (Lu,Gd)2SiO5 crystals, containing traces of Ce3+, Tb3+, and
Eu3+ ions, and Ce3+-doped Gd2SiO5 and (Lu,Gd)2SiO5 crystals are studied. For the first time,
the TSL glow curves of these materials are measured separately for the electron (intrinsic,
Ce3+- or Tb3+-related) and hole (Eu3+-related) recombination luminescence, and the TSL glow
curve peaks, arising from thermal decay of various electron and hole centers, are identified.
The origin of the traps related to the TSL peaks is discussed, and thermal stability parameters
of the electron and hole traps are calculated.

Journal of Luminescence

DOI:10.1016/j.jlumin.2014.11.034

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Studies of radiation defects in cerium, europium and terbium activated oxyfluoride glasses and glass ceramics

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E. Elsts , U. Rogulis, K. Bulindzs, K. Smits, A. Zolotarjovs, L. Trinkler, K. Kundzins

Terbium, cerium and europium activated oxyfluoride glasses and glass ceramics have been studied by
thermally stimulated luminescence (TSL) and optical absorption techniques after the X-ray irradiation.
A creation of colour centres in oxyfluoride glass matrix and TSL peaks depending on the activator type
were observed. LaF3 and rare earth activators were analysed by SEM–EDS.

Optical Materials 41 (2015) 90–93

DOI: 10.1016/j.optmat.2014.10.042

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TSL and fractional glow study of Ge-doped α-quartz.

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A. Zolatarjovs, A.N. Trukhin, K. Smits, D. Millers

Abstract. Crystalline α-quartz doped with 0.1wt% and 0.9wt% germanium was studied using
TSL and FGT equipment. Sample was chosen because previously it is known that Ge in quartz
is efficient trap for electrons, therefore it could be used for detection of hypothetic self-trapped
hole in α-quartz. However previous investigations of ODMR and TSL shows that in α-quartz
the hole is still mobile and trapping occurs only on defect states. The activation energies for
both TSL peaks are found by fractional glow and Hoogenstraaten method. The TSL
distribution changes depending on Ge concentration and also on irradiation type. The TSL
peaks below 70K in quartz doped with Ge could belong to hole trapped on Ge.

IOP Conference Series: Materials Science and Engineering 49 (2013) 012056

doi:10.1088/1757-899X/49/1/012056

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