UP-CONVERSION FLUORESCENCE SPECTROSCOPY OF ER3+ YB3+-DOPED HEAVY-METAL BI2O3-NA2O-NB2O5-GEO2 GLASS/

Upconversion fluorescence emission of Er3+/Yb3+-doped Bi2O3-Na2O-Nb2O5 -GeO2 heavy metal glass samples excited at 1.06 mu m is experimentally investigated. The results reveal the existence of intense emission ba nds centered around 520, 545, and 655 nm. The germano-niobate based ho st glass presents high transparency in the region of 400-2700 nm, the capability of incorporating high dopant concentrations, high melting t emperature, and large resistance to atmospheric moisture. The observed intensity of the green fluorescence emission, suggested that the niob ium based host glass material plays an important role in the efficienc y of the upconversion process. Emission lines centered at 425, 483, 50 3, 608, and 628 nm were also observed. (C) 1997 American Institute of Physics.