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This work applies the methods of statistical mechanics to two processes relevant to thermoluminescence; (1) the charging of traps, and (2) the discharging of traps. Assuming thermal and diffusive equilibrium, we calculate the trap ionization probabilities over a wide temperature range and for a variety of traps in YAG:Ce. The goal is to investigate whether a statistical approach yields results consistent with experimental thermoluminescence observations. We are able to reproduce with good accuracy the glow curves of several traps observed in YAG:Ce. Our calculated glow curves are shown to be consistent with systems exhibiting second order kinetics. For systems of traps that are at or near thermal and diffusive equilibrium with the conduction electrons, the results indicate that the position of a glow curve peaks is determined by two factors: the trap depths and the density of conduction electrons. • Statistical approach to thermoluminescence in YAG:Ce is presented. • Glow curve peaks based on statistical approach show a good fit to observed experimental data. • Glow curve peak positions depend on trap depths and conduction electron density. • The theoretical glow curve band structure using the statistical approach is consistent with second-order kinetics. [ABSTRACT FROM AUTHOR]

A statistical model based on the condition of thermal and diffusive equilibrium between the conduction electrons and the electrons in the excited 5d 1 level of Ce3+ is presented. Using this model, we find the probability for an excited Ce3+ ion to be thermally ionized leading to an electron in the conduction band. The density of conduction electrons is then calculated over a wide range of temperatures and excitation densities. The observed quenching of emission at high temperature in Ce-doped YAG with low Ce concentrations is also investigated within this model. It is shown that the experimentally-observed nonradiative losses in this phosphor can be reasonably simulated assuming losses occur via nonradiative decay from the conduction band to the Ce3+ ground state. • We present a model of thermal ionization in YAG:Ce leading to conduction electrons. • The density of conduction electrons in YAG:Ce is calculated. • Conduction electron trapping by Ce4+ explains losses in YAG:Ce at high temperatures. • Discrepancy between activation energy and ionization energy is explained. [ABSTRACT FROM AUTHOR]