36dB gain in S-band EDFA with distributed ASE suppression

An EDFA hybrid gain control technique for extended input power and dynamic gain ranges with suppressed transients

“…At all five levels of gain considered during the experiments, the EDFA was submitted to five different input channel loads (2,4,8,16, and 32 channels). At each channel load, for each gain level, the surviving channel gain was measured before and after add/drop.…”

“…A brief list would certainly mention the development of new types of erbium doped fiber, including fibers with high erbium concentration, primarily for L band use [1], as well as depressed cladding fibers for S band applications [2]. Together with the availability of 980-nm pump lasers packaged in mini-DIL capsules, these advances allowed the proposal of circuit configurations for better gain and noise figure performances, embedded chromatic dispersion compensation and multi-band operation [3].…”

Efficient S-Band Amplification Using Depressed-Cladding Erbium-Doped Silica Fibers

“…Thus, supression of the ASE power from the C-band is fundamental to increase the gain effficiency and allow optical amplification in the S band. A few years ago, a new erbium doped fiber was proposed as an all silica solution for S band amplification [2]. This new S band erbium doped silica fiber employs a depressed cladding refractive index profile in order to provide a high attenuation cutoff filter for long wavelengths, above 1530 nm, allowing more efficient amplification for S-band wavelengths.…”

S Band EDFA Using Standard Erbium Doped Fiber, 1450 nm Pumping and Single Stage ASE Filtering

“…Upon proper bending, this fiber is capable of filtering out the undesired C and L ASE bands and provides useful S-band gain. Many investigations reporting S-Band EDFAs based on this fiber have been published [4][5].…”