Spectroscopic properties of Nd-doped phosphate glass with a high emission cross section

Abstract

Neodymium doped phosphate glasses have been prepared by the semi-continuous melting technique. Their absorption and emission spectra have been recorded at room temperature. The Judd-Ofelt theory has been applied to evaluate the stimulated emission cross sections of 4F3/2→4I11/2 transition for Nd3+. The higher stimulated emission cross section, 4.0×10-20cm2, is obtained. The fluorescence decays of the 4F3/2→4I11/2 transition of Nd3+ are measured for the samples doped (0.7-10) wt% of Nd2O3 at room temperature. The concentration quenching of Nd-doped phosphate glass is mainly attributed to cross-relaxation and energy migration. The site-dependent properties of fluorescence spectra and the fluorescence lifetime of the Nd3+-doped phosphate glass (with 2.2wt% Nd2O3) are studied using laser-induced fluorescence line narrowing techniques and the site-to-site variations of optical properties are observed at low temperature.