掺Nd3+增益导引-折射率交叉导引光纤激光器阈值特性分析
Threshold characteristic analysis on Nd3+-doped gain-guided index-crossover guided fiber laser

研究了单端泵浦条件下掺Nd3+增益导引 折射率交叉导引（GG ICG）光纤激光器的阈值特性。建立了单端泵浦条件下改进的速率方程，通过解析解得到了阈值泵浦功率，并分析了阈值泵浦功率与Nd3+掺杂浓度（N），光纤长度（L），纤芯半径（a）以及输出镜反射率（R2s）之间的关系，并给出了理论解释。研究结果表明，当N=1×1020 cm-3，L=1 cm，a=45 μm，R1s=1，R2s=0.85时，对应的激光阈值最低，为2.95 W。研究结果对光纤激光器的优化设计具有重要的意义。
The threshold characteristics of Nd3+ doped gain guided index crossover guided (GG ICG) fiber lasers under the end pumped condition are investigated.The threshold equation is deduced from the rate equations.The effects of Nd3+ concentration (N),fiber length (L),core radius (a),and mirror reflectivity(R2s) on the threshold pump power are discussed.The results show that when N=1×1020 cm-3,L=1 cm,a=45 μm,R1s=1,and R2s=0.85,the threshold pump power is the lowest,2.95 W.It has important significance for the optimal design of the fiber laser