^{7}F_{6}(Γ_{1g}) → (Γ_{1g})^{5}D_{4} Two-Photon Transition of Tb^{3+} in Cs_{2}NaTbCl_{6}

• Authors: M. Chua , P. Tanner
• Languages of publication: EN

Abstracts

EN

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 ^{7}F_{6}(Γ_{1g}) → ^{5}D_{4} of Tb^{3+} in Cs_{2}NaTbCl_{6} has been performed, based on third-order perturbation theory including electric dipoles and spin-orbit coupling. The core 4f^{7} (^{8}S_{7/2}} Γ_{6}, Γ_{7}, Γ_{8}) and 4f^{7}(^{6}P_{7/2} Γ_{6}, Γ_{7}, Γ_{8}) states coupled with 5d(Γ_{3}, Γ_{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 ^{7}F_{6}(Γ_{1g}) → ( Γ_{1g})^{5}D_{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.

Keywords

EN

33.80.Wz; 33.20.Kf; 33.70.Fd

Discipline

• 33.80.Wz: Other multiphoton processes
• 33.20.Kf: Visible spectra
• 33.70.Fd: Absolute and relative line and band intensities

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 1996
• Volume: 90
• Issue: 1
• Pages: 169-180

Dates

published

1996-07

Contributors

author

M. Chua

• Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong

author

P. Tanner

• Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong

Identifiers

DOI

10.12693/APhysPolA.90.169