Optical properties of Er3+ in Ca3Gd2(BO3)4 crystal

Ca3Gd2(BO3)4:Er3+ crystals of high optical quality with a large size up to ∅25 mm × 60 mm were grown by Czochralski method. The absorption spectra of the crystal in three mutually perpendicular arbitrary directions at room temperature were measured. Based on Judd-Ofelt theory and a least square fit of calculated three perpendicular directions and averaged results of the absorption line intensity (referred to as TPM method), the intensity parameters Ωt (t = 2, 4, 6), the radiative transition rates, the radiative lifetimes, the fluorescence branching ratios, the experimental and theoretical oscillator strengths were obtained. The fluorescence spectrum and decay curve under the excitation of 530 nm were presented too. The stimulated emission cross-section and radiative quantum efficiency were also diplayed.