Thermoluminescence of Al2O3 crystals grown by temperature gradient techniques

Abstract

Color center concentrations of the Al2O3 crystal grown by temperature gradient techniques were calculated from Gaussian fits to absorption spectra. The concentrations for F- and F +-centers at 204, 232, and 255 nm were determined to be 1.361×1017, 0.098×1017, and 0.325×1017cm-3, respectively. Studies have shown that the thermoluminescence (TL) glow curve exhibits a prominent 450 K peak that matches well the first-order fitting curve. The thermal activation energy E and frequency factor s of the trap were determined to be 0.94456±0.00545 eV and 5.8703×1011 s-1. With this theoretical analysis, a simple one-trap/one-center TL model is presented to provide a theoretical explanation of the TL process. © 2013 The Author(s).