Experimental study on pulsed gamma-ray radiation-induced absorption in optical fibers

Abstract

The general effect mechanism of pulsed gamma-ray on optical fibers is introduced. In order to measure pulsed gammaray radiation-induced loss, a transient experimental measurement system is developed. It employs pulsed diode lasers with five wavelengths as detecting carriers and high dose rate electron accelerator as irradiation source. The radiationinduced loss of pulsed gamma-ray on conventional single mode and multi-mode optical fibers are measured respectively. The experiment of two rare-earth-doped fibers spontaneous emission spectrum measurement system is established and the results of Er-doped and Yb-doped fibers are obtained also. Experimental results show that: (1) Radiation-induced loss is relevant to the fiber types. On the same experimental condition of pulsed gamma-ray radiation, the radiationinduced loss of multimode fibers is larger than single-mode fibers. (2) Radiation-induced loss will increase as the laser detecting wavelength shifts from near-infrared to visible regions of optical spectrum. (3) As the total dose increases, the spontaneous emission spectrum of the doped fibers decreases greatly, and the performance of the doped fiber will fail at a certain total dose.