Thermal Effect on the Cathodo- and Thermoluminescence Emission of Natural Topaz (Al2SiO4(F,OH)2)

The authors report about the influence of temperature on the thermoluminescence (TL) and cathodoluminescence (CL) behavior of a well-characterized topaz from Badajoz, Spain. Cryogenic treatments induce drastic decrease on the CL and TL intensity over 400 nm involving OAl* intrinsic defects and iron point defects. It suggests that low-energy emissions should be more associated with point defects and low wavebands to structural or intrinsic defects in the lattice. The tests of thermal stability of the UV-blue TL signal at different temperatures (in the range of 473–673 K) seem to confirm a continuous trap distribution system.