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arXiv · 0911.3960

Design and fabrication of an intrinsically gain flattened Erbium doped fiber amplifier

B. Nagaraju·M. C. Paul·M. Pal·A. Pal·Ravi K. Varshney·B. P. Pal·S. K. Bhadra·Gérard Monnom·Bernard Dussardier
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Abstract

We report design and subsequent fabrication of an intrinsically gain flattened Erbium doped fiber amplifier (EDFA) based on a highly asymmetrical and concentric dual-core fiber, inner core of which was only partially doped. Phase-resonant optical coupling between the two cores was so tailored through optimization of its refractive index profile parameters that the longer wavelengths within the C-band experience relatively higher amplification compared to the shorter wavelengths thereby reducing the difference in the well-known tilt in the gains between the shorter and longer wavelength regions. The fabricated EDFA exhibited a median gain ?28 dB (gain excursion below $\pm$2.2 dB within the C-band) when 16 simultaneous standard signal channels were launched by keeping the I/P level for each at ?20 dBm/ channel. Such EDFAs should be attractive for deployment in metro networks, where economics is a premium, because it would cut down the cost on gain flattening filter head.

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B. Nagaraju, M. C. Paul, M. Pal, A. Pal, Ravi K. Varshney, B. P. Pal, S. K. Bhadra, Gérard Monnom, Bernard Dussardier. 2009-11-20. Design and fabrication of an intrinsically gain flattened Erbium doped fiber amplifier. https://doi.org/10.1016/j.optcom.2009.02.063

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