The presence of defect states in the band gap is an essential ingredient of recent models of photoinduced second-harmonic generation (SHG) in fibers. We have created such states by doping aluminosilicate glass fibers that do not contain Ge with Ce or Eu and observed SHG from 1.06-µm light after preparation of the fibers with 0.532- and 1.06-µm light. In an aluminosilicate fiber doped with 0.008 wt. % Ce, the SHG conversion efficiency is as high as 1.5% at infrared (1.06-µm) peak powers of 200 W.
© 1991 Optical Society of America
D. M. Krol and J. R. Simpson, "Photoinduced second-harmonic generation in rare-earth-doped aluminosilicate optical fibers," Opt. Lett. 16, 1650-1652 (1991)