不同掺杂浓度光纤拉曼增益特性的研究

Study on the Raman gain spectrum of different GeO_2-doped silica fiber

研究了受激拉曼散射增益系数和增益谱与泵浦功率、光纤掺杂浓度的关系,得出增益系数和峰值频移量由光纤特性决定,而与泵浦功率无关的结论。在对二氧化硅分子建模计算后,进一步利用LM算法对光纤的拉曼增益谱进行高斯分解。分解图谱表明掺杂物破坏了二氧化硅的分子结构,并在拉曼增益范围内产生了新的峰值,从理论上证明了光纤掺杂物对拉曼增益系数和增益谱的影响。

Experiments were made to investigate how the spectrum of the stimulated Raman scatting gain changes with germania concentration and different pump power. The calculated results show that the Raman gain coefficient is determined by fiber characteristics and has nothing to do with pump power. Based on the establishment of a model of silicon dioxide structure, the effect of germania concentration across the fiber core on Raman gain spectrum was analyzed by the method of Gaussian decomposition. The decomposed spectrum showed that the dopants destroyed the silicon dioxide structure and produced some new Raman gains within the discussed Raman gain range, which verified the experiment conclusion for the influences of germania concentration on Raman gain coefficient and Raman gain spectrum.