Tunnelling recombination in conventional, post-infrared and post-infrared multi-elevated temperature IRSL signals in microcline K-feldspar

In this manuscript, we study three different types of infrared stimulated luminescence signals (IRSL) from a microcline K-feldspar. These signals consist of conventional infrared (IR) stimulation measured at elevated temperatures, multi-elevated temperature post-infrared IRSL signals (MET-pIRIR), and post-infrared IRSL (pIRIR) signals. All three types of signals were analysed using analytical expressions previously derived according to a model based on quantum tunnelling. For the purpose of identifying various tunnelling components, de-convolution analysis was used based on continuous wave infrared stimulation (CW-IRSL), as well as de-convolution based on pseudo linearly modulated transformation of the signals (pLM-IRSL). The variation of the parameters with stimulation temperature was determined using both of these de-convolution methods of analysis. The luminescence curves and normalized signals were investigated at various temperatures using several related protocols. The results of this analysis have implications for the understanding of the emission of luminescence in this material during the above-mentioned protocols, and they highlight the strengths and shortfalls of the tunnelling recombination models. The results from this study contribute to a better understanding of the origin of pIRIR and MET-pIRIR luminescence signals.