Analysis of thermally stimulated luminescence and conductivity without quasi-equilibrium approximation

Abstract

Thermally stimulated luminescence (TSL) and conductivity (TSC) are considered using the classical insulator model that assumes one kind of the active trap, one kind of inactive deep trap, and one kind of the recombination center. Kinetic equations describing the model are solved numerically without and with the use of the quasiequilibrium (QE) approximation. The QE state parameter q I ,, the relative recombination probability γ, and a new parameter called quasi-stationary (QS) state parameter q*=q I γ are used for the analysis of the TSL and TSC. The TSL and TSC curves and the temperature dependences of q I , q*, γ, the recombination lifetime, and the occupancies of active traps and recombination centers are numerically calculated for five sets of kinetic parameters and different heating rates. These calculation results show that: (1) the upper limit of the heating rate for presence of the QS state appears at higher heating rate than that for the QE state when the retrapping process is present, and (2) the TSL (TSC) curves in the QS state have the properties similar to those for the TSL (TSC) curves in the QE state. Approximate formulas for calculation of the parameters q I and q* in the initial range of the TSL and TSC curves are derived and used in the heating-rate methods, proposed in this work, for determination of those parameters from the calculated TSL curves.

The deconvolution of thermoluminescence glow-curves using general expressions derived from the one trap-one recombination (OTOR) level model

“…Sunta et al (1999Sunta et al ( , 2001Sunta et al ( and 2005 suggested that the apparent dominance of first-order kinetics in nature is usually due to slow re-trapping, but in multipletrap model, it may occur under fast re-trapping conditions as well. Some authors described the prevalence of first-order shape peaks with deep trap as the reason (Haering and Adams, 1960 ;Dussel and Bube, 1967;Bohm and Scharmann, 1971;Simmons and Taylor, 1972;Agersap Larsen et al, 1999;Opanowicz, 2007). Pagonis and Kitis (2012) have also ascribed the first-order or nearly first-order property to the competition among the traps.…”