Thermo-stimulated luminescence of x-ray- and alpha-irradiated yttria-stabilized zirconia.
Yttria-stabilized zirconia (ZrO2 : Y3+) single crystals (with 9.5 mol% Y2O3) were irradiated with x-rays and α particles. Thermally stimulated luminescence (TSL) data show a main broad peak centred at ∼500-550 K in the glow curves of all irradiated samples. The TSL peak maximum temperature is consistent with the characteristic recovery temperature (∼450 K) of colour centres (T centres) deduced from isochronal annealing curves measured by electron paramagnetic resonance (EPR) spectroscopy. However, the trap-depth energies (ranging between 0.8 and 1.2 eV) deduced from the initial rise of partially cleaned TSL peaks (and from a rough approximation using Urbach's formula) are much larger than the activation energies for defect recovery of 0.3 eV deduced from the EPR data. A second TSL peak centred at ∼350-450 K found in freshly irradiated samples is seen to decay substantially in aged samples. The processes involved in TSL are discussed in relation to the defect annealing processes, and available defect-level energy and TSL data.
CEA, DEN, SRMA, F-91191 Gif-sur Yvette Cedex, France. jean-marc.costantini@cea.fr
Jean-Marc
JM
Costantini
François
F
Beuneu
Mauro
M
Fasoli
Anna
A
Galli
Anna
A
Vedda
Marco
M
Martini