Charge Traps in Ce-Doped CaF2\text{}_{2} and BaF2\text{}_{2}

Thermoluminescence of CaF$\text{}_{2}$:Ce, BaF$\text{}_{2}$, and BaF$\text{}_{2}$:Ce irradiated at room temperature is reported. X-ray induced emission spectra of the samples show that both excitonic (due to e$\text{}^{-}$+V$\text{}_{K}$ recombination) and Ce$\text{}^{3+}$ d-f luminescence may contribute to thermoluminescence signal. The simple Randall-Wilkins model is used to deconvolute glow curves into seven to eight first-order peaks. Parameters of all traps are calculated and correlations between peaks in the curves of the examined materials are discussed

Luminescence from β-Irradiated Graphene Layers

We found that β-irradiated samples of crystallite graphite and multi-walled carbon nanotubes emit light during heating above room temperature. This behaviour is rather surprising for semimetals. Due to the lack of deep enough energy gap, this optical emission cannot be associated with interband transitions, as it is usually assumed in a thermally stimulated luminescence model. We suppose that the reported accumulated luminescence is the result of thermally stimulated relaxation of some kind of defects created in graphene structures by ionising radiation and therefore we offer to name it the relaxoluminescence. We anticipate the relaxoluminescence to be a starting point for developing a new spectroscopic method for nanotechnology. It can also throw a new light on the nature of defects, which are suspected of being responsible for strange magnetic effects in carbon

Quartz luminescence applied in palaeoenvironmental reconstruction of a dune

Optically stimulated luminescence (OSL) and thermoluminescence (TL) dating were applied for studying the evolution of a dune at the archaeological site of Kałdus (Lower Vistula Valley, Poland), where excavation revealed a settlement sequence. The dating results are supported by investigations of optical bleaching characteristics of the dune quartz. The luminescence studies presented here are a part of a wider interdisciplinary project studying the dynamics of the local geomorphology and its relationship to human activity at the site from prehistoric times until early medieval ages