Abstract

Fiber lasers made from Nd³⁺-doped silica operate efficiently at 1088 and 938 nm, corresponding tothe⁴F_3/2-⁴I_11/2,⁴I_9/2 transitions in glass^1,2 but not on the ⁴F_3/2—⁴I_13/2 transition which normally occurs at 1370 nm.³ it has been supposed that this is due to excited-state absorption in the fiber, but thus far no detailed measurements have been reported. We report here measurements of gain and excited- state absorption over the 900-1400-nm wavelength range covering the three common transitions in Nd:glass lasers. The results confirm a strong pump-induced absorption centered at 1300 nm.

© 1988 Optical Society of America