Abstract

Pump lasers for Er³⁺-doped silica fiber optical amplifiers must demonstrate excellent spatial mode stability to high output power levels in order to achieve useful gain.^1,2 The pump band at 980 nm is the most efficient of the principle Er³⁺ absorption bands in terms of gain per input optical power.³ Pumping at 980 nm is also preferred in comparison to pumping at 1480 nm because it reduces the noise introduced into the amplified optical signal.⁴

© 1991 Optical Society of America