Spectroscopic Properties of Sr1−Xndylax−Ymgxal12−Xo19 Shaped Crystal Fibers Grown by the Micro-Pulling-Down Method

Nd3+-doped Sr0.7La0.3Mg0.3Al11.7O19 and LaMgAl12O19 shaped crystal fibers have been successfully grown by the micro-pulling-down (μ-PD) method for the first time. The polarized absorption spectra, fluorescence spectra and fluorescence lifetime decay curves were measured at room temperature. The most intense emission peak of 5 at.% Nd:Sr0.7La0.3Mg0.3Al11.7O19 crystal fiber appears at 1052 nm with the full width at half maximum (FWHM) of 6.8 nm for σ polarization and at 1052 nm with FWHM of 6.9 nm for π polarization, respectively. The decay lifetimes of 4F3/2 level state of Nd:ASL shaped crystal fibers with different neodymium concentration were calculated. All the results show that Nd:ASL crystal fiber has potential as a laser gain medium for ultrashort and tunable laser system.