Trap spectroscopy and tunnelling luminescence in feldspars

Abstract Comparative studies of tunnel luminescence, thermally stimulated luminescence (TSL), and trap energy spectra by the fractional glow technique (FGT) have been made both with sanidine and microcline feldspars. After X-irradiation at LNT these feldspars show intense tunnelling afterglow. As the temperature is raised, several TSL glow peaks may be observed, starting at 135 K. An intense peak at 250 K is common to all four investigated microclines. In samples of sanidine, tunnelling afterglow overcomes TSL up to 250–260 K. With sanidine and microcline samples, the distributions of trap activation energies vs temperature obtained by the FGT are continuous and quasi-linear. Maxima in the …