High performance C+L-band EDFA enhanced by using a long-period fiber grating

A simple method to improve gain bandwidth of double-pass C+L-band erbium-doped fiber amplifier (EDFA) is demonstrated by using Bi/Er co-doped fiber (BEDF) and a long-period fiber grating. The achieved 20 dB gain bandwidth is up to 78 nm, covering 1530-1608 nm, with a minimum noise figure of 4.8 dB.