【摘要】 光纤纤芯中不同的掺杂分布对高功率多模光纤振荡器输出特性有重要的影响。通过建立多模光纤振荡器理论模型,求解光纤振荡器速率方程组,数值模拟了均匀型及抛物线型Yb3+掺杂的双包层增益光纤接入激光器时的输出特性;并针对纤芯75%区域内均匀掺杂Yb3+的情况,通过引入模式耦合系数矩阵,分析了掺杂分布对光纤振荡器输出特性的影响。计算结果表明,不同的Yb3+掺杂分布对振荡输出特性的影响存在差异;通过设计光纤内Yb3+掺杂分布规律和形状,可有效抑制多模光纤振荡器中的高阶模式,从而使多模光纤振荡器实现基模输出。更多还原

【Abstract】 A theoretical model of high power multimode fiber oscillator is built based on rate equations of the multimode Yb3+doped fiber considering improvement of the mode coupling in the core.The effect of Yb3+dopant profiles in the core on the output characteristics of fiber oscillator is carried out.The output characteristics of the high power multimode fiber oscillator with flat and parabolic dopant profiles fibers are described respectively.The output characteristics of the fiber oscillator with 75%flat dopant profiles fibers in different coupling coefficients are described.The results show that the different Yb3+dopant profiles may have different impacts on the output characteristics.Specially,the fundamental mode output can be achieved by designing and controlling the Yb3+dopant profiles.更多还原