The optical loss coefficient at 1053-nm wavelength, influenced by Fe ions in N31-type Nd-doped phosphate laser glass, was determined precisely and analyzed in detail. It is found that the optical loss coefficient per unit of Fe concentration (cm^(-1)/ppmw) increases with Fe concentration in the range of 0---300 ppmw, but it approaches a constant as the Fe concentration is larger than 300 ppmw. Such a concentration effect is due to a shift in the redox equilibrium between Fe3+ and Fe2+ ions in the glass. The effect of oxygen pressure, temperature, and variable valence states of other metal ions in glass samples on the optical loss is also discussed.
© 2005 Chinese Optics Letters
(140.3530) Lasers and laser optics : Lasers, neodymium
(160.2750) Materials : Glass and other amorphous materials
(160.6990) Materials : Transition-metal-doped materials
(300.1030) Spectroscopy : Absorption
Yongchun Xu, Shunguang Li, Lili Hu, and Wei Chen, "Effect of Fe impurity on the optical loss of Nd-doped phosphate laser glass," Chin. Opt. Lett. 3, 701-704 (2005)