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arXiv · 1310.4228

Luminescence of cadmium fluoride doped with rare-earth ions

Evgeny Radzhabov·Roman Shendrik
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Abstract

Absorption, excitation and emission spectra of cadmium fluoride crystals doped with rare-earth ions were investigated. In contrast to alkaline-earth fluorides the absorption spectra due to 4f - 5d transitions of Ce$^{3+}$, Pr$^{3+}$ and Tb$^{3+}$ ions are broadened. No 5d-4f emissions were observed. These prove that 5d(e$_g$) levels of rare earth ions lie in conduction band of CdF$_2$ crystal. Emission spectra of Tb$^{3+}$ show the group of 4f-4f $^5$D$_4$-$^7$F$_j$ lines in contrast to other alkaline-earth fluorides where emission due to $^5$D$_3$-$^7$F$_j$ transitions is also observed. The absence of the emission is due to position of $^5$D$_3$ level within condution band. Among the all measured crystals doped with impurity ions (Pr, Nd, Eu, Ho, Tb, Tm, Yb, Ga, In or Mn), the CdF$_2$ doped with Pr$^{3+}$, Tb$^{3+}$, or Mn$^{2+}$ ions have the highest light outputs under x-ray excitation.

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Evgeny Radzhabov, Roman Shendrik. 2013-10-15. Luminescence of cadmium fluoride doped with rare-earth ions. https://doi.org/10.1109/tns.2013.2284488

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