Combined Temperature and Radiation Effects on the Gain of Er- and Er–Yb-Doped Fiber Amplifiers

Abstract

We investigated the coupled radiation and temperature effect on the gain degradation of erbium-doped fiber amplifier (EDFA) and erbium-ytterbium-doped fiber amplifier (EYDFA). The irradiation temperatures range from -40 °C to 120 °C. Steady-state X-ray (40 keV, 300 krad (SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ), ~27 rad/s) experiments provide evidence for a minor coupled radiation and temperature effect on the gains of both reference and radiation-tolerant EDFA and EYDFA. This is an important result as it validates the reliance on room-temperature testing in establishing the suitability of fiber amplifiers for space applications. Furthermore, we also investigated the radiation-induced attenuation (RIA) kinetics during and after the various rare-earth-doped fiber irradiations to improve our knowledge of the basic radiation-effects mechanisms and their dependence on the temperature during irradiation. It appears that these effects also depend on the presence of cerium, a codopant that is incorporated to passivate the Al- or P-related defects and then to enhance the amplifier radiation tolerance.