Diode-pumped laser operation at 1053 and 900 nm in Sr_(1-x)La _(x-y)Nd_yMg_xAl_(12-x)O_(19) (Nd:ASL) single crystal

摘要

Neodymium-doped strontium lanthanum magnesium aluminoxide (Sr _(1-x)La_(x-y)Nd)yMg_xAl _(12-x)O_(19), Nd:ASL) single crystals were grown by the Czochralski technique. Branching ratios for both transitions ~4F _(3/2)→~4I_(9/2) (900 nm) and ~4F _(3/2)→~4I_(11/2) (1053 nm) were calculated to be 45% by the Judd-Ofelt theory based on polarized absorption spectra of Nd ~(3+). The spectroscopic quality factors (X = Ω_4/ Ω_6) of X = 0.87 for σ polarization and X = 1.55 for π polarization were calculated for 7 at.% Nd:ASL crystal. Quantum efficiency was calculated to be 74%. Laser operation was pumped by a 792 nm LD source. By adopting 7 at.% Nd:ASL crystal as gain media, output power of 5.7 W and slope efficiency of 50% were obtained at 1053 nm with output coupler T = 9.79% and achromatic lens focus of 75 and 150 mm. Output power of 6.9 W and slope efficiency of 36% at 1053 nm, together with output power of 1.72 W and slope efficiency of 17% at 900 nm were obtained in 5 at.% Nd:ASL crystal.