Yb:Ca9Gd(VO4)7, a potential ultrafast pulse laser crystal with promising spectral properties

The Yb3+:Ca9Gd(VO4)7 crystal with dimensions of Φ19 × 25 mm3 was grown by the Czochralski method for the first time. The polycrystalline materials, crystal growth, absorption and fluorescence spectra, energy level schema, fluorescence lifetime and laser performance parameters were investigated in detail. For π-polarization, the absorption coefficients, cross-sections, maximal full width at half maximum (FWHM) at around 976 nm are 1.05 cm−1, 1.27 × 10−20 cm2 and 33 nm, respectively. For σ-polarization, the relevant absorption spectral parameters at around 981 nm are 1.58 cm−1, 1.90 × 10−20 cm2 and 28 nm, respectively. At the laser wavelength around 1023 nm, the FWHM and emission cross-sections are 57 nm and 0.94 × 10−20 cm2 for π-polarization, 54 nm and 2.18 × 10−20 cm2 for σ-polarization, respectively. The results reveal that Yb3+:Ca9Gd(VO4)7 crystal can be regarded as a potential candidate for efficient LD-pumping and ultrashort pulse laser crystal.