Thermoluminescence and optically stimulated luminescence properties of nanocrystalline Er3+ and Yb3+ doped Y3Al5O12 exposed to β-rays

The thermoluminescence (TL) and optically stimulated luminescence (OSL) characterization of Er3+ and Yb3+ doped Y3Al5O12 nanocrystalline samples prepared by the precipitation process and exposed to beta-rays are discussed. The TL as well as the OSL were two orders of magnitude higher in Er3+ doped than in Yb3+ specimens. The charge trapping and the radiative thermally stimulated recombination processes in Y3Al5O12:Er3+ involve four trapping states at 166, 243, 342 and 424 degrees C, but just two trapping levels at 219 and 413 degrees C for Y3Al5O12:Yb3+ at a heating rate of 10 degrees C s(-1). The photostimulation with 470 nm light causes in both phosphors a radiative recombination of the optically free charge carriers belonging to the same trapping states. The TL and the OSL as a function of radiation dose behaviour were linear in the 10-100 Gy dose range. The results provide evidence of the potential uses of these materials in radiation storage and dosimeter devices.