摘要
We study the photodarkening effect in a double clad ytterbium-doped silica fiber fabricated by modified chemical vapor deposition and solution doping.A common measurement technology for photodarkening is used to study the photodarkening-induced absorption spectra.We present a fast and simple method to observe the PD effect by measurement of the fluorescence spectra.The method proposed here can be used to observe the influence for a short time,and thus reduces the requirements of system stability and heat management.It is obtained that under the condition of 45.5%Yb ion inversion level,photodarkening-induced excessive loss at an equilibrium state is above 4.5 dB/m and florescence intensity degradation is above 10%after 500 min pumping at 1041 nm for the home-made normal Yb/Al co-doped silica fiber.
基金
Supported by the National High-Technology Research and Development Program of China under Grant Nos 2013AA031501 and 2011AA030201.
作者简介
Corresponding author:李进延,Email:ljy@mail.hust.edu.cn。
