Multi-stage optical fiber amplifier having high conversion efficiency

摘要

We have found that the conversion efficiency of a Er/Yb-doped cladding pumped fiber amplifier increases with increasing signal input power. Thus, preamplification of the input signal by means of an Er-doped fiber amplifier can result in increased conversion efficiency of the cladding pumped power amplifier. Such increased efficiency is desirable, lessening heat removal problems and/or facilitating increased reliability.