High Gain Erbium-Doped Traveling Wave Fiber Amplifier.
01 January 1987
Traveling-wave amplification of a lambda = 1.53microns signal with +22 dB gain is achieved at 295 K in an Er sup 3+ doped single-mode fiber using a lambda = 514.5 nm pump source. The optimum fiber length for maximum gain is determined experimentally. A limit in signal-to- noise ratio due to concurrent amplification of spontaneous emission is observed. By colling the fiber to 77K, the amplifier gain is increased to +29 dB, due to depopulation of the lower laser level.