Comparison of the spectra and dynamics of Er3+:Y2−xScxO3 (x = 0, 1, 2)

We have studied the spectra and lifetimes of Er3+ in the isostructural series, Y2O3, YScO3. Addition of Sc3+ to Er3+:Y2O3 shifted the energy level positions, changed the inhomogeneous broadening and shortened the fluorescence lifetimes for Er3+ in the C2 site. Going from Er3+:Y2O3 to Er3+: Sc2O3 increased the barycenter of the four lowest J-multiples, decreased the barycenter of the 4F92 and higher multiplets, and increased the crystal-field splitting within each J-multiplet. The inhomogenous line widths in the Er3+:YScO3 spectra were much larger than in Er3+:Y2O3 or Er3+: Sc2O3 due to random substitutional disorder in the mixed system. The random disorder in Er3+:YScO3 removed the inversion symmetry of the C31 lattice site and allowed observation of transitions from Er3+ ions in this site. All fluorescence lifetimes decreased with addition of Sc3+ indicating an increase in the nonradiative relaxation.