Growth, structure and spectroscopic properties of 1 at.% Er³⁺: GdTaO₄ laser crystal

1 at% Er³⁺ doped Er: GdTaO₄ laser crystal with high optical quality was successfully grown by the Czochralski method. The structural parameters were obtained by the X-ray Rietveld refinement. A high crystalline quality of Er: GdTaO₄ was determined by the X-ray rocking curve. The transition intensity parameters of Er³⁺ ions were fitted according to the absorption spectra along three principal polarization directions. The relatively larger emission cross section (1.022×10⁻²⁰ cm²), long fluorescence lifetime ( 5.66 ms) and relatively weaker reabsorption phenomenon around 1.6 µm indicate that 1 at% Er: GdTaO₄ crystal can be used as a promising NIR laser material. Meanwhile, the stimulated emission cross-section spectra along three principal polarization directions were investigated for ⁴I_13/2 →⁴I_15/2 transitions at 1.5–1.6 µm which indicates a great potential of Er: GdTaO₄ for multi-wavelength emission at 1.5–1.6 µm. In addition, the possibility of generating green and red lasers in Er: GdTaO₄ was also analyzed and evaluated.