Optical spectroscopy of NaLa(WO4)2:Dy3+ single crystal

NaLa(WO4)2:Dy3+ crystals were grown successfully by the Czochraski technique. The Raman, infrared, electronic absorption and emission spectra were measured at room temperature. The Judd–Ofelt theory, extended to anisotropic system, has been applied to evaluate the intensity parameters Ωt (t = 2, 4, 6), radiative transition rates A, radiative lifetimes τR, and fluorescent branching ratios β. Although there are several transitions originating in the 4F9/2 level, a major part of emission intensity is contained in the 4F9/2 → 6H13/2 transition. The stimulated emission cross-sections for this transition were estimated by using the Füchtbauer–Ladenburg method. The luminescence decay curve was also measured at room temperature. The results indicate that NaLa(WO4)2:Dy3+ may be considered as laser active materials operating near 0.57 μm.