A Two-Stage S-Band Erbium-Doped Fiber Amplifier Based on W-type Erbium-Doped Fiber

An S-band erbium-doped fiber (EDF) amplifier based on a W-type EDF designed by ourselves is demonstrated by employing a two-stage double-pass configuration. The amplifier provides a bandwidth of 34 nm (1486-1520 nm) for the gain over 20 dB. The maximal gain of 32.8 dB is achieved at 1501 nm and the corresponding noise figure is 6.0 dB. The proposed amplifier has a promising foreground in extending the current network to the S band.