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arXiv:1909.02633 · Physical Review A

Direct observation of a highly forbidden optical transition in Sm:SrF2

Mohit Verma, Luca G. Talamo, Hiromitsu Sawaoka, Amar C. Vutha

Published Sep 3, 2019• 2 citations
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Abstract

The $4{f}^{6}\phantom{\rule{0.28em}{0ex}}{}^{7}{F}_{0}\ensuremath{\rightarrow}4{f}^{6}{}^{5}{D}_{0}$ intraconfiguration transition in $\mathrm{Sm}:{\mathrm{SrF}}_{2}$ is forbidden for ${\mathrm{Sm}}^{2+}$ ions in the octahedrally symmetric substitution sites in ${\mathrm{SrF}}_{2}$. We report the direct observation of this transition using laser-induced fluorescence at cryogenic temperatures, and measurements of the excited-state lifetime and the excitation cross section. To the best of our knowledge, this optical transition has the longest-lived excited state ever observed in a solid.

DOI
10.1103/physreva.100.032502

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