Vacuum ultraviolet spectra and crystal field analysis ofYAlO3doped withNd3+andEr3+

Abstract

The synchrotron radiation excited emission and excitation spectra are reported at temperatures of 298 and $10\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ for ${\mathrm{YAlO}}_{3}$ (YAP) doped with $1\phantom{\rule{0.3em}{0ex}}\mathrm{at.}\phantom{\rule{0.2em}{0ex}}%$ ${\mathrm{Nd}}^{3+}$ or ${\mathrm{Er}}^{3+}$. For both systems, no $d\text{\ensuremath{-}}f$ emission is observed and these results are rationalized and compared with other hosts. For $\mathrm{YAP}:{\mathrm{Nd}}^{3+}$, excitation into the $4{f}^{2}5d$ electronic configuration of ${\mathrm{Nd}}^{3+}$ gives intraconfigurational luminescence from $^{2}G(2)_{9∕2}$ and $^{4}F_{3∕2}$ and there is no evidence for emission from other multiplet terms. Luminescence from $^{2}P_{3∕2}$ is observed for $\mathrm{YAP}:{\mathrm{Er}}^{3+}$, with additional transitions from $^{4}S_{3∕2}$, $^{4}F_{9∕2}$, $^{4}I_{9∕2}$, and $^{4}I_{11∕2}$. The emission spectra have been assigned in detail. The literature energy level datasets are mostly consistent with the derived energy levels from the present study. The $f\text{\ensuremath{-}}d$ excitation spectra show that the lowest $d$-electron levels are energetically situated below the intrinsic absorption of the host. Crystal field analyses have been performed by using 100 energy levels for each system and the resulting standard deviations were 12.4 and $15.5\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ for ${\mathrm{Er}}^{3+}$ and ${\mathrm{Nd}}^{3+}$, respectively. The multiplet term barycenters are better fitted for the case of ${\mathrm{Nd}}^{3+}$, whereas crystal field splittings are better modeled for ${\mathrm{Er}}^{3+}$. The fitted free ion parameters exhibit considerably less uncertainty for ${\mathrm{Nd}}^{3+}$.