Luminescence of Neodymium in Barium Magnesium Germanate Crystals and Glass Hosts

Abstract

The optical properties of the rare-earth dopant neodynium in crystal and glass hosts of the identical chemical composition ${\mathrm{Ba}}_2$Mg${\mathrm{Ge}}_2$ ${\mathrm{O}}_7$ have been studied on a comparative basis. This technique offers many advantages. Concentration quenching of emission is seen to commence at ${\mathrm{Nd}}^{3+}$ doping in the glass, but not at all for ${\mathrm{Nd}}^{3+}$ concentrations of up to ∼ 2 at.% in the crystal. This and other related concentration- and temperature-dependent phenomena, including multiple-lifetime effects observed in the glass, are shown to be consistent with the existence of two predominant types of resonant-energy-transfer mechanisms between ${\mathrm{Nd}}^{3+}$ ions.