Gain saturation characteristics of Raman amplification in silica and fluoride glass optical fibers

Abstract

Raman amplification in silica and fluoride glass fibers is studied experimentally and theoretically. Two tunable dye lasers are employed to provide pump and signal light. In an 80 m long silica glass fiber, a small-signal gain of 39 dB has been achieved at a pump wavelength of 580 nm. The gain bandwidth is 127 cm -1 in small-signal amplification and 250 cm -1 in saturated amplification. In an 18 m long fluoride glass fiber, a small-signal gain of 9.3 dB has been obtained. The measured Raman-gain coefficient at 580 nm is (2±0.5) × 10 -11 cm/W in the fluoride glass fiber.