Influence of glass matrix on magneto-optical activity of f-f transitions in Dy³⁺ ion

The absorption and magnetic circular dichroism spectra of f-f transitions ⁶H_15/2 ← ⁶F_3/2, ⁶F_5/2, ⁶(F_7/2 +H_5/2) and ⁶(F_9/2+H_7/2) in Dy³⁺ ion were studied in the glasses: Dy₂O₃-P₂O ₅-SiO₂-GeO₂ and Dy₂O ₃-La₂O₃-Al₂O₃-B ₂O₃-SiO₂-GeO₂ with different concentrations of Dy³⁺ ions in temperature range 100-300 K. Basing on this data, absolute values and temperature dependences of the paramagnetic magneto-optical activity (MOA) of the transitions were determined. The origin of the MOA of f-f transitions was analyzed with the help of two models. In the first model, MOA is considered as a consequence of admixture of states with opposite parity by odd components of crystal field. The second approach is based on the Judd-Ofelt theory. The same f-f transitions reveal different values and temperature dependences in different glasses, what testifies to a different symmetry of the nearest environment of Dy³⁺ ions in these glasses.