Fiber amplification in the 940-nm water vapor absorption band using the F-4(3/2)->I-4(9/2) transition in Nd

The measurement of atmospheric mater vapor in the 940-nm absorption band may be accomplished using fiber amplifiers based on the F-4(3/2) --> I-4(9/2) transition in Nd. We report initial experimental results on the effects codopants have on the characteristics of this transition in Nd-doped fiber, and present modeled and experimental results of a fiber amplifier. To our knowledge, this is the first reported fiber amplifier employing this transition.