Gain equalization in C+L erbium-doped fiber amplifiers

An apparatus comprising:

• a C-band amplification section;
• an L-band amplification section;
• a first gain flattening filter (GFF) for performing C-band gain equalization, the first GFF coupled and arranged subsequent to the C-band amplification section;
• a second GFF, different from the first GFF, for performing L-band gain equalization, the second GFF coupled and arranged subsequent to the L-band amplification section;
• a first optical isolator arranged or coupled between the first EDF of the C-band amplification section and the first GFF;
• and
• a second optical isolator arranged or coupled between the second EDF of the L-band amplification section and the second GFF;
• wherein the C-band amplification section includes at least a first erbium doped fiber (EDF) for amplifying a C-band optical signal;
• wherein the L-band amplification section includes at least a second EDF for amplifying an L-band optical signal;
• wherein the C-band amplification section and the L-band amplification section are configured in a parallel arrangement;
• and
• wherein at least the first and second optical isolators and the first and second GFFs form a hybrid component.