- Tytuł:
- $\text{}^{7}$F$\text{}_{6}$(Γ$\text{}_{1g}$) → (Γ$\text{}_{1g}$)$\text{}^{5}$D$\text{}_{4}$ Two-Photon Transition of Tb$\text{}^{3+}$ in Cs$\text{}_{2}$NaTbCl$\text{}_{6}$
- Autorzy:
-
Chua, M.
Tanner, P. A. - Powiązania:
- https://bibliotekanauki.pl/articles/1945539.pdf
- Data publikacji:
- 1996-07
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
33.80.Wz
33.20.Kf
33.70.Fd - Opis:
- Two-photon spectroscopy has expanded the scope of studies of excited states of ions and has also enabled the examination of the validity of conventional theories. In this study, the direct theoretical calculation of the two-photon intraconfigurational crystal field transitions of $\text{}^{7}$F$\text{}_{6}$(Γ$\text{}_{1g}$) → $\text{}^{5}$D$\text{}_{4}$ of Tb$\text{}^{3+}$ in Cs$\text{}_{2}$NaTbCl$\text{}_{6}$ has been performed, based on third-order perturbation theory including electric dipoles and spin-orbit coupling. The core 4f$\text{}^{7}$ ($\text{}^{8}$S $\text{}_{7}\text{}_{/}\text{}_{2}$ Γ$\text{}_{6}$, Γ$\text{}_{7}$, Γ$\text{}_{8}$) and 4f$\text{}^{7}$($\text{}^{6}$P $\text{}_{7}\text{}_{/}\text{}_{2}$ Γ$\text{}_{6}$, Γ$\text{}_{7}$, Γ$\text{}_{8}$) states coupled with 5d(Γ$\text{}_{3}$, Γ$\text{}_{5}$) are taken as the intermediate states. The calculated transition intensity ratios are in good agreement with the experimental results. In particular the two-photon transition $\text{}^{7}$F$\text{}_{6}$(Γ$\text{}_{1g}$) → ( Γ$\text{}_{1g}$)$\text{}^{5}$D$\text{}_{4}$ is allowed in third-order perturbation instead of the proposed fourth-order process by Ceulemans et al. using the Judd-Pooler-Downer model. The inconsistency between the two studies arises from the failure of application of the Judd-Ofelt closure approximation. The closure approximation does not only simplify the two-photon calculation but also sacrifices the physical accuracy by changing the selection rule of the two-photon transition from that of two electric dipole transitions to that of one electric quadrupole transition.
- Źródło:
-
Acta Physica Polonica A; 1996, 90, 1; 169-180
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki