Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5399792 | Journal of Luminescence | 2014 | 6 Pages |
Abstract
Luminescence and photo-thermally stimulated defects creation processes are studied for a Pr3+-doped PbWO4 crystal at 4.2-400Â K under excitation in the band-to-band, exciton, and charge-transfer transitions regions, as well as in the Pr3+-related absorption bands. Emission spectra of Pr3+ centers depend on the excitation energy, indicating the presence of Pr3+ centers of two types. The origin of these centers is discussed. The 2.03-2.06Â eV emission, arising from the 1D2â3H4 transitions of Pr3+ ions, is found to be effectively excited in a broad intense absorption band peaking at 4.2Â K at 3.92Â eV. By analogy with some other Pr3+-doped compounds, this band is suggested to arise from an electron transfer from an impurity Pr3+ ion to the crystal lattice W6+ or Pb2+ ions. The dynamics of the Pr3+-related excited states is clarified. In the PbWO4:Pr crystal studied, the concentration of single oxygen and lead vacancies as traps for electrons and holes is found to be negligible.
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
E. Auffray, M. Korjik, T. Shalapska, S. Zazubovich,