VUV excited luminescence and thermoluminescence investigation on Er&lt;sup&gt;3+&lt;/sup&gt;- or Pr&lt;sup&gt;3+&lt;/sup&gt;-doped BaY&lt;sub&gt;2&lt;/sub&gt;F&lt;sub&gt;8&lt;/sub&gt; single crystals

Andrade, Adriano B.; da C. Bispo, Giordano F.; Macedo, Zélia S.; Baldochi, Sonia L.; Yukihara, Eduardo G.; Valerio, Mário E.G.

doi:10.1016/j.optmat.2019.02.044

VUV excited luminescence and thermoluminescence investigation on Er³⁺- or Pr³⁺-doped BaY₂F₈ single crystals

Andrade AB, da C. Bispo GF, Macedo ZS, Baldochi SL, Yukihara EG & Valerio MEG

Citation

Andrade, A. B., da C. Bispo, G. F., Macedo, Z. S., Baldochi, S. L., Yukihara, E. G., & Valerio, M. E. G. (2019). VUV excited luminescence and thermoluminescence investigation on Er³⁺- or Pr³⁺-doped BaY₂F₈ single crystals. Optical Materials, 90, 238-243. https://doi.org/10.1016/j.optmat.2019.02.044

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:28574

Photoluminescence (PL), thermoluminescence (TL) emission spectra and TL glow curves of barium yttrium fluoride (BaY₂F₈ - BaYF), undoped and doped with erbium (Er³⁺) or praseodymium (Pr³⁺) were measured to investigate the fundamental absorption (band gap – E_g), the nature of the trapping centers, as well as the electronic transitions of Ln³⁺ in BaYF host. The band gap energy E_g of BaY₂F₈ was determined by vacuum ultraviolet (VUV) excitation measurements to be around 11.2 eV. Additionally, the electronic transition from excited states of Ln³⁺ ions and the exciton state were also identified. TL emission spectra showed that the TL emission of doped samples is related to the Ln³⁺ ion, indicating that the related host trapping centers are not affected by the new trapping centers originated due the dopant ions. Trap depths were calculated by fitting the glow curves using a first order kinetics model. Host-related trapping centers were attributed to intrinsic defects such as V_k and F centers and the new TL peaks observed for Er- and Pr-doped samples was associated to the electrons trapping centers. These results lead us to propose a simple model to explain the origin of the TL emission in BaYF.