Investigation of efficient pump scheme for Pr/sup 3+/-doped fluoride fiber amplifiers

Numerical analysis reveals that a bi-directional pump scheme suppresses the population reduction of the /sup 1/G/sub 4/ level due to pump ESA and cooperative upconversion. It is confirmed experimentally that the gain coefficient increases from 0.21 to 0.24 dB/mW, which is the maximum single pass gain coefficient ever reported, with the bi-directional pump scheme. It is shown that this pump scheme is effective in extracting the potential of Pr/sup 3+/-doped fluoride fibers.<
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