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arXiv · 1211.0376

Vacuum ultraviolet 5d$^1$4f$^9$-4f$^{10}$ emission of Ho$^{3+}$ ions in alkaline-earth fluorides

E. A. Radzhabov·V. Nagirnyi·A. I. Nepomnyashchikh
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Abstract

Time-resolved emission, excitation as well as emission decay curves of CaF$_2$, SrF$_2$, BaF$_2$ doped with HoF$_3$ were investigated. Most intensive emission bands near 168 nm, having long decay time, belong to spin-forbidden transitions from 5d$^1$4f$^9$ high spin (HS) states to ground $^5$I$_8$ states of Ho$^{3+}$ ions. Weak spin allowed 5d$^1$4f$^9$(LS)-4f$^{10}$ emission band at 158 nm was observed only in CaF$_2$-Ho crystals. Spin allowed and spin-forbidden excitation bands were observed in all crystals near 166 and 155 nm respectively. Fast component of spin-forbidden emissions due to multiphonon relaxation to low-lying 4f$^{10}$ Ho$^{3+}$ level was observed for all crystals.

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E. A. Radzhabov, V. Nagirnyi, A. I. Nepomnyashchikh. 2012-11-02. Vacuum ultraviolet 5d$^1$4f$^9$-4f$^{10}$ emission of Ho$^{3+}$ ions in alkaline-earth fluorides. https://arxiv.org/abs/1211.0376

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