Spectroscopic properties of Yb3+ in heavy metal contained fluorophosphate glasses

A new series of 20Bi(PO{sub 3}){sub 3}-10Sr(PO{sub 3}){sub 2}-35BaF{sub 2}-35MgF{sub 2} doped with Yb{sup 3+} is introduced for fiber and waveguide laser applications. The stimulated emission cross-section {sigma} {sub emi}, which was found to be 1.37 pm{sup 2} at the lasing wavelength of 996 nm, is the highest one among fluorophosphate glasses. It has been found that an extremely high gain coefficient of G = 1.65 ms pm{sup 4} and high quantum efficiency of {eta} = 93% for 1 wt.% Yb{sub 2}O{sub 3} doped systems. The various concentration effects on laser performance properties including minimum pumping intensity I {sub min}, the minimum fraction of excited ions {beta} {sub min} and the saturation pumping intensity I {sub sat} are analyzed as a function of Yb{sub 2}O{sub 3} concentration. Those results obtained in current system had advantage over some fluorophosphate glasses reported.