Modified absorption attributes of neodymium doped magnesium-zinc-sulfophosphate glass

Rare-earth doped glass systems with improved absorption and emission features are greatly demanding for diverse applications. In this endavour, selection of right glass host, modifier, rare earth ions with optimized composition is the key issue. This communication reports the conventional melt-quench synthesis of neodymium (Nd 3+ ) doped magnesium-zinc- sulfophosphate glass system of the form (60- x )P 2 O 5 -20MgO-20ZnSO 4 - x Nd 2 O 3 ( x = 0, 0.5, 1, 1.5, 2.0 and 2.5 mol%). The influence of varying Nd 3+ contents on the physical (density, molar volume, molar refractivity, refractive index and electronic polarizability) and absorption properties of the prepared glass system is determined. The amorphousity of the obtained samples is confirmed by XRD analysis. The glass refractive indices (ranged from 1.85 to 1.90)  and densites (between 2.63 to 2.77 g.cm -3 ) are found to increase with increasing concentration of Nd 3+ ion. Furthermore, the energies associated with the direct and indirect optical transitions across the forbidden gap are observed to reduce with the increase of Nd 3+ ion concentration. Meanwhile, the increase of Urbach energy with increasing Nd 3+ doping is ascribed to the interaction of rare earth ions with the ligands of the glass network and subsequent transformation of weak bonds into defects. The room temperature UV–Vis-NIR spectra revealed eleven absorption band corresponding to the transitions from the ground state to various excited states of the Nd 3+ ion. Incorporation of  Nd 3+ ion is discerned to enhance the glass absorbance appreciably together with the alteration of physical properties. Present findings may be beneficial for the advancement of Nd 3+ ions doped magnesium-zinc-sulfophosphate glass system based photonic devices especially for infrared solid state laser.