Quantum tunneling processes in feldspars: Using thermoluminescence signals in thermochronometry

Abstract During the past decade, our understanding of the nature of quantum tunneling processes in luminescence materials has been advanced significantly, by both experimental work and modeling insights into the underlying luminescence mechanism. This paper provides examples of analysis of thermoluminescence (TL) signals in feldspars, based on recent modeling work which showed that the shape of the TL glow curves remains practically unchanged after thermal and/or optical treatment of the samples. Analysis of the experimental TL glow curves in thermally or optically pretreated feldspars shows that these signals can be described as the sum of several Gaussian curves. While the positions and height of these Gaussians depend on the thermal and optical history of the sample, the width of the Gaussians apparently remains the same across the TL glow curve. TL glow curves are analyzed for 10 different samples, and the width of the Gaussian curves is found to be a common property characterizing all samples, at least within experimental error. Specifically it is found that the Gaussian width stays practically unchanged when the irradiated samples undergo thermal treatments for different times and temperatures, or alternatively when they undergo optical bleaching treatments with blue LEDs. The common overall shape of the TL glow curves has important implications for the use of these signals in thermochronometry.