Nd3+:YAG microspheres powders prepared by spray pyrolysis: Synthesis, characterization and random laser application

Nd3+:YAG crystals have been used to develop photonic devices since the 1960s. Its unique properties, which stem from the combination of the YAG structure with lanthanide ions, have made it the most widely employed material in commercial solid-state lasers. This work reports the synthesis of dense Nd3+:YAG particles prepared by spray pyrolysis. During the synthesis, no clusters emerged, and the particles did not coalesce even after thermal treatment at 1100 °C. All characterization confirmed that the YAG phase was obtained as a spherical micro- and sub-micrometric material. In addition, the photoluminescence spectra showed the expected spectroscopic profile of Nd3+ replacing Y3+ at the dodecahedral sites. The presence of high Nd3+ concentration was exploited as a simultaneous gain and scatter medium for random laser application. The spray pyrolysis methodology described could be easily scaled up for a pilot setup or industrial production. Further applications as sensors or superluminescent sources can be envisaged.