Article

Radiation Effects on Ytterbium- and Ytterbium/Erbium-Doped Double-Clad Optical Fibers

DIF, CEA, Bruyeres-le-Chatel, France
IEEE Transactions on Nuclear Science (Impact Factor: 1.22). 01/2009; 56(Part 1):3293 - 3299. DOI: 10.1109/TNS.2009.2033999
Source: IEEE Xplore

ABSTRACT We characterize by different spectroscopic techniques the radiation effects on ytterbium- (Yb) and ytterbium/erbium (Yb/Er)-doped optical fibers. Their vulnerability to the environment of outer space is evaluated through passive radiation-induced attenuation (RIA) measurements during and after exposure to 10 keV X-rays, 1 MeV ¿-rays, and 105 MeV protons. These fibers present higher levels of RIA (1000×) than telecommunication-type fibers. Measured RIA is comparable for ¿-rays and protons and is on the order of 1 dB/m at 1.55 ¿ m after a few tenths of a kilorad. Their host matrix codoped with aluminum (Al) and/or phosphorus (P) is mainly responsible for their enhanced radiation sensitivity. Thanks to the major improvements of the Er-doped glass spectroscopic properties in case of Yb-codoping, Yb/Er-doped fibers appear as very promising candidates for outer space applications. In the infrared part of the spectrum, losses in P-codoped Yb-doped fibers are due to the P1 center that absorbs around 1.6 ¿ m and are very detrimental for the operation of Er-codoped devices in a harsh environment. The negative impact of this defect seems reduced in the case of Al and P-codoping.

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