硼锗共掺光纤CCG的载氢研究

Research on the Hydrogen-Load of B-Ge Co-Doped Fiber Chemical Composition Grating

为研究载氢的作用对由载氢引起的硼锗共掺光纤CCG的形成及其热稳定性进行实验,利用硼锗掺杂物浓度分别为w(Ge)=9.640%,w(B)=0.475%和w(Ge)=28.277%,w(B)=2.375%的光纤进行对比试验.实验结果显示:相同载氢条件下高浓度的Ge离子更容易导致FBG在高温退化,并获得CCG的高温稳定性;对于相同掺杂的光纤,氢元素能提高CCG的反射比,但同时也引起光栅反射比在高温时不稳定.通过对上述两种影响因素的优化,实验获得了传感范围在10～1 010℃,反射比接近40%的高温稳定光栅.

To explore the effect of hydrogen-loading on B-Ge co-doped fiber chemical composition grating （CCG）, the thermal stability and generating property of B-Ge co-doped fiber CCG caused by hydrogen-loading have been experimentally studied. Different dopant concentrations of two fibers have been used as the subjects for comparison, one is w（Ge） = 9. 640% with w（B） = 0.475% and the other is w（Ge）=28.277% with w（B）=2.375%. The result shows that, with the same conditions of hydrogen-loading and high temperature, the higher concentration of germanium in the fiber is, the easier to bring about the decay of fiber Bragg grating （FBG） and the thermal instability of CCG is. For the same fibers with different hydrogen-loading conditions, hydrogen would increase the reflectance of grating, but make its stability worse. By trial, the excellent thermal sensor with better stability in high temperature condition is fabricated, which can be used in the range from 10-1010 ℃ with reflectance of about 40%.