Spectral noise figure of Er/sup 3+/-doped fiber amplifiers

The erbium-doped fiber amplifier noise figure spectrum and its evolution under various pumping regimes is analyzed. The analysis shows that noise figures in the range +or-0.15 dB around the 3-dB quantum limit are possible within a spectral band of 50 nm. This demonstrates the possibility of quantum-limited amplification for broadband wavelength-division multiplexed (WDM) signals.<
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