Chakravarty Usha, Mukhopadhyay P K, Kuruvilla A, Upadhyaya B N, Bindra K S
Appl Opt. 2017 May 1;56(13):3783-3788. doi: 10.1364/AO.56.003783.
A narrow-linewidth broadly tunable Yb-doped Q-switched fiber laser using an acousto-optic modulator and multimode interference filter (MMIF) in the linear bulk cavity resonator and an all-fiber ring cavity resonator has been demonstrated. Insertion of an MMIF in the linear cavity resonator using bulk components decreased the spectral bandwidth of the Q-switched signal by two orders of magnitude from 11 to less than 0.1 nm. Spectral tunability of more than 16 nm in the range from 1057 to 1073 nm has also been achieved by the combination of MMIF and a standard polarization controller (SPC). A decrease in the pulse duration with a decrease in the spectral bandwidth of the output signal has also been recorded. The pulse duration of the Q-switched signal was reduced from ∼305 to ∼240 ns by the introduction of the MMIF in the resonator at the same value of the input pump power. In the case of the all-fiber Q-switched ring cavity resonator, the spectral bandwidth of the Q-switched signal was reduced by two orders of magnitude from ∼17 to less than 0.1 nm due to the introduction of the MMIF in the resonator. The spectral tunability of more than 12 nm in the range from 1038 to 1050 nm was achieved by an MMIF and an SPC.
已展示了一种窄线宽、宽调谐的掺镱调Q光纤激光器，其在线性体腔谐振器中使用了声光调制器和多模干涉滤波器（MMIF）以及全光纤环形腔谐振器。在使用体元件的线性腔谐振器中插入MMIF，使调Q信号的光谱带宽从11nm降低了两个数量级，降至小于0.1nm。通过MMIF与标准偏振控制器（SPC）的组合，在1057至1073nm范围内还实现了超过16nm的光谱调谐。还记录到随着输出信号光谱带宽的减小，脉冲持续时间也减小。在相同输入泵浦功率值下，通过在谐振器中引入MMIF，调Q信号的脉冲持续时间从约305ns减小到约240ns。在全光纤调Q环形腔谐振器的情况下，由于在谐振器中引入了MMIF，调Q信号的光谱带宽从约17nm降低了两个数量级，降至小于0.1nm。通过MMIF和SPC在1038至1050nm范围内实现了超过12nm的光谱调谐。
