Thermoluminescence and kinetic parameters of Dy3+-doped LiYF4

This work reports the kinetics of charge carriers in Dy3+-doped LiYF4 by means of thermoluminescence (TL) and isothermal luminescence decay (ITL) analyses, where the activation energy for all traps was calculated. LiYF4:Dy was synthesized by a microwave-assisted hydrothermal method. The crystalline structure was studied by X-ray diffraction, refined using Rietveld method. We have investigated TL emission as function of both temperature and wavelength. The influence of heating rate on peak position (temperature of maximum TL intensity), the dose-response curve, and activation energy obtained from the fitting of glow curves and isothermal decay. The results demonstrate that the Dy3+ ion should act as a stable trap at room temperature. TL glow curve was registered after irradiating the samples with doses from 0.1 Gy to 100 Gy using a beta 90Sr/90Y source. From the results, it was possible to identify a first-order kinetic mechanism, with linear dose response of the maximum intensity of the main peak. On the other hand, the total area under TL curves presented sub-linear response for doses higher than 5.0 Gy, which points out to the presence of shallow traps in the material. •Thermoluminescence and isothermal luminescence in LiYF4:Dy were investigated.•Trap depths associated with Dy3+ is in perfect agreement with the Dy energy levels.•Kinetic parameters of traps were discussed.