报道了自组织反馈光纤环形激光器中施加相位调制后产生的强度混沌现象。对自组织反馈光纤环形激光器进行稍大于阈值的泵浦,通过压电陶瓷引入相位调制;保持泵浦功率及调制电压不变,改变调制频率,得出光强随不同调制频率变化的分岔图,观察到某些特定频率区域内激光器输出进入类似混沌的状态。针对类似混沌的光强输出序列进行非线性时间序列分析,通过功率谱计算、相空间重构、关联积分计算等方法得到了多段调制频率区间内光强序列具有混沌特征的证据。初步分析产生混沌的机理得出:特定条件下施加的相位调制等同于损耗调制。
For self-organized feedback fiber ring laser under the threshold pump,phase modulation is introduced by PZT.Keeping pump power and modulation voltage unchanged,introducing different modulation frequencies,the bifurcation diagram of changing light intensity with different modulation frequencies is obtained.Status similar to chaos is observed in particular frequency region.According to the bifurcation diagram,the data segment similar to chaos is selected for nonlinear time series analysis.The evidence that many intensity time series have chaotic characteristics is obtained by calculating the power spectrum,phase-space reconstruction and correlation integral.