Dehydroxylation processing and lasing properties of a Nd alumino-phosphate glass

In this work, we have studied the preparation and properties of an alumino-phosphate glass with composition 13Na 2 O-13K 2 O-16BaO-4Al 2 O 3 -54P 2 O 5 (mol%). The first part of the work deals with the study of the processing conditions of the dehydroxylation of the phosphate glass , which was performed by remelting under N 2 flow using graphite crucibles. Glass samples from 5 to 50 g and Nd 2 O 3 doped were submitted to dehydroxylation and the influence of temperature, time, mass of glass and viscosity were correlated with the content of water in the glasses through the coefficient of absorption of OH ions. The network structure of the glasses was also determined by means of 31 P and 27 Al 1D/2D nuclear magnetic resonance and the local environment of Nd 3+ ions was probed by electron paramagnetic resonance . The optimized conditions of processing were then used to obtain a dehydroxylated glass with a 2.5 wt% Nd 2 O 3 whose spectroscopic and laser emission properties were studied. The spectroscopic properties of Nd 3+ ions which include, Judd-Ofelt calculation, stimulated emission cross-section of the laser transition, lifetime, and quantum efficiency are presented. Site-selective laser spectroscopy and stimulated emission obtained under selective wavelength pumping along the 4 I 9/2 → 4 F 5/2 absorption band were performed to determine the distribution of crystal field in which the rare earth is located, together with its influence in the pump wavelength dependence of the spontaneous and laser emissions of Nd 3+ in this glass matrix.