Polarized spectroscopic properties of disordered Er3+:Gd2SrAl2O7 crystal

Abstract

A multi-position disordered Er3+:Gd2SrAl2O7 single crystal was grown by the Czochralski method. Room temperature polarized spectral properties of the crystal were investigated in detail. The Judd–Ofelt theory was applied to analyze the polarized absorption spectra. The peak stimulated emission cross-sections of the 4I13/2→4I15/2 transition reach 0.79 ×10−20 and 1.25×10−20 cm2 for σ and π polarizations, respectively. The gain curves are flat with full widths at half the maximum larger than 60 nm. Fluorescence lifetimes of the 4I13/2 multiplet for Er3+ ions were fitted to be 4.93 ms and 3.48 ms from measured fluorescence decay curves for bulk and powder samples, respectively. The results show that the Er3+:Gd2SrAl2O7 crystal may be a potential gain medium for a 1.55 µm laser with low pumping threshold.