Dokl. Akad. Nauk SSSR, 1985 Volume 283, Number 6,Pages 1339–1342(Mi dan47152)
PHYSICS
Experimental study of the $4f$–$5d$ transitions of $\mathrm{Ho}^{3+}$, $\mathrm{Er}^{3+}$, $\mathrm{Tm}^{3+}$, and $\mathrm{Yb}^{3+}$ in $\mathrm{BaY}_2\mathrm{F}_8$