Study of radiation induced effects in the luminescence of nanostructured Al₂O₃: Yb, Er crystals

Alumina crystals doped with Yb and Er were obtained by sol gel process and their morphologies and luminescence properties were discussed. Nanocrystals formations composed by Er₂O₃, Yb₂O₃ e Yb₃Al₅O₁₂ were observed by TEM images, EDS, electron beam diffraction and XRD, at the surface of the alumina grains. The size of the nanocrystals were of about (36±2) nm and (182±8) nm for the samples calcinated at 1200^oC and 1600^oC, respectively. The sample codoped with 1mol% of Er and 2 mol% of Yb supplied the best results for Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL). The growth intensity of dosimetric TL peak at 205^oC was linear with gamma radiation doses and the same behavior was observed in OSL results.