A study was made of the colour centre production in yttria-stabilized zirconia (ZrO2:Y3+) by heavy ion irradiation in the GeV range using on-line UV–visible optical absorption spectroscopy. Experiments were performed with 11.4MeV amu − 1 127Xe, 197Au, 208Pb and 238U ion irradiations at 8K or room temperature. A broad and asymmetrical absorption band peaked at a wavelength about 500nm was recorded regardless of the irradiation parameters, in agreement with previous room temperature irradiations with heavy ions in the 100MeV range. This band was de-convoluted into two broad Gaussian-shaped bands centred at photon energies about 2.4 and 3.1eV that were respectively associated with the F+-type centres (involving a singly ionized oxygen vacancy, VO·) and T centres (i.e. Zr3+ in a trigonal symmetry) observed by electron paramagnetic resonance spectroscopy. In the case of 8K Au ion irradiation at low fluences, six bands were used at about 1.9, 2.3, 2.7, 3.1 and 4.0eV. The three bands near 2.0–2.5eV could be assigned to oxygen divacancies (i.e. F2 + centres). No significant effect of the irradiation temperature was found on the widths of all absorption bands for the same ion and fluence. This was attributed to the inhomogeneous broadening arising from the static disorder due to the native charge-compensating oxygen vacancies. However, the colour centre production yield was strongly enhanced at 8K with respect to room temperature. When heating irradiated samples from 8K to room temperature, the extra colour centres produced at low temperature did not recover completely to the level of room temperature irradiation. The latter results were accounted for by an electronically driven defect recovery process.

Generation of Colour Centres in Yttria-Stabilized Zirconia by Heavy Ion Irradiations in the GeV Range. J.M.Costantini, F.Beuneu, K.Schwartz, C.Trautmann: Journal of Physics - Condensed Matter, 2010, 22[31], 315402