Structural detuning of pump absorption rate in doped fiber for the enhancement of power conversion efficiency

We propose a novel doped fiber structure along with its design criteria, for the enhancement of power conversion efficiency in L-band erbium doped fiber amplifier. With proper adjustments on doping profiles for the reduction of pump absorption rate, it becomes possible to optimize pump evolution map inside the doped fiber to get better power efficiency, while suppressing the development of pump-depleting, detrimental ASE. Exemplary analysis shows significant enhancement in the saturation output power of more than 2.0 dB, when compared to conventional doping profiles.