A study of NIR emission and associated spectroscopic properties of Nd3+:P2O5+K2O+Al2O3+ZnF2 glasses for 1.06 μm laser applications

For studying spectroscopic properties of 1.06 μm laser emission, zincfluorophosphate glasses(PKAZf) with varying of Nd2O3 concentration were fabricated by the melt-quenching technique. Amorphous nature, thermal stability and physical properties of glasses were studied in detail. The optical band gap of PKAZfNd1.0 glass was estimated for indirect(3.21 eV) and direct(3.34 eV) transitions. The radiative parameters like radiative emission probability, radiative lifetime, branching ratio, and effective line width were calculated for 4F3/2→4I13/2,11/2,9/2 transitions. With 808 nm irradiation, the NIR emission spectra showed a strong band at 1.06 μm (4F3/2→4I11/2), and two less intensity bands at 1.33 μm (4F3/2→4I13/2) and 0.89 μm (4F3/2→4I9/2). The decay curves were fitted to the double exponential function and the decrease of lifetimes from 261 to 208 μs was observed. The PKAZfNd1.0 glass provides some favorable spectroscopic parameters: high gain (125.61 × 10−25 cm2s) and low threshold (1.67 × 108 W/m2) properties, including stimulated emission cross-section (4.74 × 10−20 cm2) and quantum efficiency (89%).