Design and fabrication of erbium-doped fibers for optical amplifiers

Erbium-doped optical fibers are designed using the refractive index differe nce, fiber core diameter and Er concentration as parameters in the numerica l calculations. The fibers are fabricated with modified chemical vapor depo sition and solution doping techniques, which are described in detail. Prefo rm and fiber parameters also measured at several laboratories participating in the European Community's COST 217 project are given and compared with t he fiber design values. The produced Er fiber is utilized in prototype fibe r amplifiers. The differential efficiency of an Al-doped Er fiber is measur ed to be 77%. (C) 2000 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(00)02207-8].