Reconstruction of the thermally quenched glow‐curve of Al₂O₃:C

Abstract

The experimental glow‐curve of Al2O3:C is highly disturbed due to the strong thermal quenching effect present in this material. Therefore, the real glow‐curve shape of this material is unknown. The present work describes an attempt to reconstruct the glow‐curve shape of Al2O3:C samples with different TL peak structures. The reconstruction procedure is performed in two steps. In the first step, the very narrow glow‐curves are fitted with the product of known kinetic equations and the expression giving the thermal quenching efficiency. From this procedure the quenching parameters are estimated. Next, the experimental glow curves are reconstructed (corrected for thermal quenching) dividing them by the quenching efficiency using the evaluated parameters from the first step. This step was applied to all types of glow curve structures. It was found that the quenching parameters estimated from the above procedure for Al2O3:C are in very good agreement with those reported in the literature. The results indicate that the method can be used as an alternative method for the evaluation of the quenching parameters and the reconstruction of the real (without quenching) glow‐curves of various materials. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Simulation of the influence of thermal quenching on thermoluminescence glow‐peaks

“…A direct curve fitting using Eq. (13) is not practical and is limited only to single TL peaks, provided that in the temperature region of the TL glow‐peak the η ( T ) values are not too low 16. It is, therefore, useful to examine how well the analytical expression I ( T ) can fit a thermally quenched glow‐peak.…”

“…(1) to zero, it is found that the value of thermal quenching efficiency at its maximum variation rate (in absolute values) is given by: where T nm is the temperature of the maximum $|\eta _{\rm m} |$ . Since, usually it is $kT_{{\rm nm}} \ll W$ , it was found by Dallas et al 16 that $n_{\rm m} = 0.54 \pm 0.007$ for every W , C pair. This value of n m is useful for selecting the simulated glow‐peaks.…”

Роль дырочных ловушек в термолюминесценции дозиметрического пика в анион-дефектных монокристаллах alpha-Al-=SUB=-2-=/SUB=-O-=SUB=-3-=/SUB=-

“…При этом уширение пика происходит в сторону более высоких температур, что вызывает смещение в высокотемпера-турную область положения его максимума. В ряде об-разцов кривая ТЛ имеет ярко выраженную двухпиковую структуру [5][6][7].…”

“…Есть мнение, что основной пик может быть обусловлен равномерным распределением лову-шек по энергии, ширина которого коррелирует с по-лушириной пика [4]. Аппроксимация широкого ТЛ-пика уравнением общего порядка кинетики, учитывающим две ловушки, была проведена другими авторами [6]. В работе [7] было показано, что в образцах с узкими и уширенными ТЛ-пиками наблюдаются различия в до-зовых зависимостях параметров ТЛ.…”

A novel fitting method for evaluating the thermal quenching parameters of TL with an application to undoped CVD diamond

“…For many TL materials this way is not suitable because of low TL sensitivity or complicated schemes of TL processes that can involve additional channels of electron transfer 6. Therefore, a number of methods for the evaluation of the TQ parameters based on an analysis of a series of TL glow curves recorded with variable heating rates were proposed 9–12.…”