TRAP SPECTROSCOPY AND TSL IN FELDSPARS

Many feldspars cannot be used in dosimetry and dating as they display anomalous fading of TSL due to tunnel recombination. With alkali felds pars, this effect is stronger with sanidines, with a 'disordered' latt ice, than with microclines, with 'ordered' lattice. Comparative studie s are made of tunnel luminescence, TSL, and spectra of trap depths mea sured by initial rise and fractional glow technique (FGT). TSL and FGT are made after X ray irradiation at LNT. In TSL, some grow peaks at 1 35 and 250 K are observed mostly in microclines. In FGT, the main obse rvation is a continuous distribution of trap depths, from 100K to 500K , linear with temperature from nearly zero to 1.6eV. These observation s are in agreement with the 'order/disorder' situation in feldspars. I t results in predominance of localised states and charge carrier migra tions analogous to situations in glasses or amorphous materials.