Polarization analysis in double-pass erbium-doped fiber amplifiers with an embedded-DCF module

Two configurations of double-pass erbium-doped fiber amplifiers with an embedded dispersion-compensating module are evaluated under changes of the input optical polarization. The first configuration employs the usual combination of a polarization-beam splitter and a Faraday rotator mirror (FRM), while the second is based on the use of two circulators. The amplifiers are characterized in terms of polarization-dependent gain, noise figure, and BER. It is demonstrated that the topology employing circulators show much improved performance compared to the configuration using the FRM.