An L‐band‐cascaded erbium‐doped fiber amplifier for uniform gain without gain equalizing filter

Abstract

In the letter, a high gain‐naturally flattened L‐band erbium‐doped fiber amplifier (EDFA) is demonstrated. The system uses two bidirectionally pumped lasers for exciting Er3+ in three cascaded fiber amplifiers. The maximum gain of ∼36.4 dB and equalized gain of over 26 dB in the absence of any gain flattening filter with ∼2.5‐dB variation over 35 nm (1572–1608 nm) was obtained. Studies for varying amplifier lengths; signal power and pump powers have also been reported. The proposed EDFA has a noise figure below 5 dB and was found to be stable at extreme temperatures. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2053–2055, 2014

Electrospun Amplified Fiber Optics

“…As further confirmation of the effective amplification process, we analyzed the signal transmission at 960 and 970 nm (Figure b), finding a lower gain in agreement with the spectrum obtained by the ASE characterization (Figure c). Importantly, amplification of ∼14 dB over a length of 8 mm is comparable to or larger than the typical maximum gain obtained in other dye-doped fiber amplifiers , as well as in rare-earth-doped fibers . Considering their small size, these new fibrous systems can be considered as promising media for short-distance and pulsed amplification uses.…”

“…Importantly, the amplification of about 14 dB on a length of 8 mm, is comparable or larger than the typical maximum gain obtained in other dyedoped fiber amplifiers 12,38 as well as in rare-earth-doped fibers. 42 Considering their small size, these new fibrous systems could be considered as promising media for short-distance as well as pulsed amplification uses.…”

Multi‐wavelength L‐band gain‐clamped erbium‐doped fiber amplifier with high gain and flatness by using composite FBGS

“…To extend the operating band, long‐wavelength‐band (L‐band, 1570–1610 nm) EDFAs have received much attention since the end of 1990s. Naturally, the gain spectrum of erbium‐doped fiber (EDF) in L‐band is more flat than that in conventional‐band (C‐band, 1525–1565 nm), but the drawback is lower gain efficiency . Two‐stage and dual‐pass configurations have been proved to efficiently enhance the output gain of L‐band EDFAs .…”

Single‐/Dual‐FBG‐based gain controller of gain‐clamped L‐band erbium‐doped fiber amplifier with high gain and flatness

“…With the continuous increase of traffic, the operating band of EDFA needs to be extended from conventional‐band (C‐band, 1525–1565 nm) to long‐wavelength‐band (L‐band, 1570–1610 nm). The benefits of L‐band EDFA are that it can be easily realized by adding the length of erbium‐doped fiber (EDF) and has a more flat gain spectrum even without any equalizer . Recently, due to the bursty of traffic, the research on gain‐clamping in L‐band EDFAs has received much attention.…”