Analysis of TL and OSL kinetics in lithium magnesium phosphate crystals

Within this work the samples of the LiMgPO4 compound have been crystallized using a micro pulling down crystal growth method. The measured TL and OSL response was investigated in order to evaluate basic kinetic parameters. Collected data were analyzed using Tm-Tstop, deconvolution and variable heating rate methods. It was found that both the TL and OSL response of the LiMgPO4 samples can be expressed in the form of a linear combination of several first order components. The obtained results suggest that luminescence processes in the studied material may follow a first order kinetics, as the measured TL glow curves do not shift with increasing dose. Increasing the dose of beta radiation up to kGy range, a linear response was measured for all the studied LiMgPO4 samples. The obtained values of kinetic parameters evaluated with Tm-Tstop method remain in agreement with those obtained by deconvolution for low-temperature peaks. In turn, for peaks located at higher temperatures the results obtained by variable heating rate method are close to those of deconvolution. This implies that more detailed analysis is needed to achieve a compatibility between the applied modes of data analysis and to achieve the accurate values of kinetic parameters. By calculating a decrease in the area under the whole LMP glow curve for the two weeks fading time, using the estimated trapping parameters, and comparing the results with previous work one may conclude that Tm-Tstop method combined with the initial rise analysis gives the most reliable values of kinetic parameters.