Erbium transversal distribution influence on the effectiveness of a doped fiber:: optimization of its performance

A simple mathematical function is introduced to describe a wide assortment of dopant profiles and study its influence on an erbium-doped fiber performance. Significant gain differences are observed in active fibers similar in every respect save for their erbium transversal distributions (ETD). It is found that a well-known overlapping parameter turns out to be suitable to characterize the active fiber transversal properties. Optimization of the active fiber performance reduces to maximizing such parameter. Thanks to this fact, the most appropriate ETD is easy to find, which constitutes an interesting information for active fiber designers. (C) 2001 Elsevier Science B.V. All rights reserved.