Spectroscopic properties of Dy3+-doped NaBi(WO4)2 crystal

Abstract

Abstract A Dy3+-doped NaBi(WO4)2 crystal was successfully grown by the Czochralski method. Spectroscopic properties of the crystal at room temperature were measured and analyzed. Peak absorption cross-sections of the 6H15/2 → 4I15/2 transition for the crystal are 1.4 × 10-21 and 2.3 × 10-21 cm2 with full widths at half maximum of 7.5 and 6.6 nm for σ and π polarizations, respectively, and at 454 nm for both polarizations. Meanwhile, the crystal exhibits a strong yellow emission at 574 nm corresponding to the 4F9/2 → 6H13/2 transition with peak cross-sections of 0.97 × 10-20 and 1.27 × 10-20 cm2 for σ and π polarizations, respectively. The fluorescence lifetime and quantum efficiency of the 4F9/2 multiplet were estimated to be 179 μs and 80%, respectively. It has been found that the cross relaxation plays an important role in the relaxation of the 4F9/2 multiplet. The results show that the Dy3+:NaBi(WO4)2 crystal may be a promising gain medium of the 574 nm yellow laser pumped by a blue laser diode at 454 nm.