Tb(3+) Ion Optical and Magneto-Optical Properties in the Cubic Crystals KTb(3)F(10)

The optical and magneto-optical characteristics of KTb(3)F(10) crystals in the transition region of (5)D(4) → (7)F(6) 4f(8) configurations of the Tb(3+) ion at temperatures of 90 and 300 K were studied. The schemes of the optical transitions in the KTb(3)F(10) crystals were constructed, and the energies of most of the Stark sublevels of the ground (7)F(6) and excited (5)D(4) multiplets of the Tb(3+) ion split by the C(4v) symmetry crystal environment were determined. The presence of three- and two-doublet states in the energy spectra of the Tb(3+)ion multiplets (7)F(6) and (5)D(4), respectively, was established, which is in good agreement with theoretical predictions. The use of the wavefunctions of the Stark sublevels of multiplets split by a tetragonal crystal field and combining in the studied optical transition made it possible to explain some of the magnetic and magneto-optical features observed in the KTb(3)F(10) single crystals.