Abstract
The absorption and luminescence properties of CsI(Tl) crystals colored by irradiation are studied by the method of the time-resolved spectroscopy. The scheme of the electron transitions in CsI(Tl) crystal is suggested to explain the appearance of the color centers under exposure to the near-UV light. It is established that either of the two types activator color centers holds the charge carrier with opposite sign. The model of the hole Tl2+vc - activator color center is suggested. According to the model the positive charge of Tl2+ ion is compensated by the negative charge of a close cation vacancy vc -. The color center emission reveals in the cathode-luminescence spectrum of the colored CsI(Tl) crystal. The high-dose irradiation of CsI(Tl) crystal results in the reduction of the decay time of the near-thallium self-trapped excitons (STE) emission. The decay kinetics of Tl2+vc - emission contains the time components typical for the decay kinetics of near-thallium STE emission. The reason of the observed effects is the energy transfer from the near-thallium STE excitons to the color centers via the inductive-resonant mechanism.
Original language | English |
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Pages (from-to) | 1447-1453 |
Number of pages | 7 |
Journal | Journal of Luminescence |
Volume | 128 |
Issue number | 9 |
DOIs | |
Publication status | Published - Sep 2008 |
Keywords
- Color center
- Energy transfer
- Luminescence
- Thallium-doped cesium iodide
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Atomic and Molecular Physics, and Optics