Spectroscopic study of the radiation hardening of bismuth/erbium co-doped optical fiber (BEDF) by hydrogen loading

Abstract

Targeting the improved performance and the potential implementation in terrestrial and space applications, radiation hardening of bismuth/erbium co-doped optical fiber (BEDF) by hydrogen loading has been investigated. It is evident that gamma radiation induced absorptions (RIAs) exist in BEDFs with and without H2 loaded. Thereinto, RIA of BEDF with H2 loaded is greatly suppressed. Particularly, RIA of H2 loaded BEDF at 620 nm is over 40 dB/m lower than that of BEDF without H2 loaded after 35.6 Gy gamma irradiation. Due to the RIA, the bismuth active center (BAC) emission spectra of all irradiated BEDFs are reduced. But the decrement of H2 loaded BEDF is ~1 dB less than that of the counterpart. Although the change of the BAC-Si concentration by gamma radiation is unnoticeable via the comparison of the absorption and emission spectra, the results in this work demonstrate that H2 loading is an effective radiation hardening method for potential applications of bismuth doped optical fiber (BDF) and BEDF in radiative environment.