Thermoluminescence of Sn 2 P 2 S 6 crystals

Thermoluminescence (TL) of five nominally pure Sn2P2S6 crystals was studied as a function of an exposure wavelength within wide temperature (12–360 K) and spectral (300–1200 nm) regions. After an exposure to monochromatic light with the wavelength shorter than about 710 nm at 12 K, weak TL was observed within 15–240 K. The glow curves of integral TL were fitted well by superposition of functions describing the shape of glow peak of general order kinetics. This analysis revealed 17 glow peaks with strongly sample-dependent intensities. The activation energies of thermal ionisation and frequency factors corresponding to charge carrier shallow traps related to the glow peaks were found as fitting parameters within 50–542 meV and 107–1011 s–1, respectively. TL was spectrally similar to broad-band photoluminescence in the red and near-infrared spectral regions that can be excited with monochromatic light with the wavelength shorter than about 710 nm at low temperatures. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)