Excited-state absorption at 1.3 μm in Nd3+-doped fluoride and sulfide glasses

Excited-state absorption (ESA) and emission spectra are recorded from the F-4(3/2) level of Nd3+ ions in Zr-Ba-La-Al-Na (ZBLAN) and Ba-In-Ga (BIC) fluoride glasses and in Ge-Ga-S-Cs-Cl (GGSC) chlorosulfide glass. The respective contributions of stimulated emission (SE) and ESA are determined in the 1.3 mu m region, a spectral domain that corresponds to the second telecommunication window. The pump-probe technique utilized in this study predicts the gain profile as a function wavelength in optical fibers. Gain-is expected at wavelengths greater than 1.31 mu m with ZBLAN and BIG, and 1.35 mu m with GGSC. It is shown that the relative intensities of SE and ESA processes can be evaluated with consistency by Judd-Ofelt calculations. (C) 1999 Elsevier Science B.V. All rights reserved.