全固态频移反馈激光器的谱宽稳定特性

从速率方程出发,把激光介质的增益带宽以环程频移量为单位划分为若干频带并进行移频处理,仿真分析了基于Nd∶YVO4介质的频移反馈(FSF)激光器在连续输出情况下的特性,给出了在改变抽运功率水平、声光调制器(AOM)衍射效率、环程频移量、介质增益带宽等条件下频移反馈激光器的输出谱宽、频谱位移等的仿真计算结果。实验中,采用端面抽运驻波腔结构并以声光调制器作为腔内移频器,构建了基于Nd∶YVO4介质的全固态频移反馈激光器,实验研究验证了理论计算的结果,并得到了1 W以上的连续激光输出。研究结果表明频移反馈激光器的输出频谱在不同抽运水平下具有谱宽基本稳定的特点。

Spectrum-Width Stability of All Solid-State Frequency-Shifted Feedback Laser

The continuous-wave output of the frequency-shifted feedback (FSF) laser with Nd∶YVO4 crystal was analyzed, with laser rate equations by dividing the gain spectrum of laser crystal into many bands in unit of round-trip frequency shift and frequency-shifting. The output spectrum width and spectrum shift with varied pumping power level, diffraction efficiency of acousto-optical modulator (AOM), round-trip frequency shift and gain spectrum width of laser crystal were given in details. Based on a resonator structure of end-pumping and frequency-shifter of AOM, an all solid-state FSF laser with Nd∶YVO4 crystal was constructed. The experimental results were in consistent with the simulated ones, and output power higher than 1 W is also obtained. The result proves the spectrum-width stability of the FSF laser at variant pumping levels.