新型钒酸盐混晶Nd∶Gd_(0.42)Y_(0.58)VO_4/Cr~(4+)∶YAG被动调Q锁模特性研究

研究了Nd∶Gd0.42Y0.58VO4混晶的激光运转特性。采用Cr4+∶YAG晶体作为被动可饱和吸收体,实现了Nd∶Gd0.42Y0.58VO4混晶的调Q锁模激光运转。实验测量了不同Cr4+∶YAG初始透过率情况下激光器的输出特性。在Cr4+∶YAG初始透过率T0=86.3%,输出镜透过率T=10%时,调Q锁模运转阈值为2.8 W,随着抽运功率的增加,调制深度逐渐加大。采用透过率T=20%的输出镜,注入抽运功率10.3 W时,调Q锁模深度约为70%,相应的脉冲包络重复频率为40 kHz,半高宽度为25 ns,平均输出功率为2.58 W,光-光转换效率为25%。

Study for Cr4+∶YAG Passively Q-Switched Mode-Locking Properties of a New Mixed Vanadate Crystal Nd∶Gd0.42Y0.58VO4

Passively Q-switched mode-locking Nd∶Gd0.42Y0.58VO4 laser is studied with Cr4+∶YAG as saturable absorbers. The output performance of lasers is tested for the Cr4+∶YAG at different transmission. At the initial transmission T0=86.3% for Cr4+∶YAG and the output transmission of 10% for the output coupler, the threshold power of Q-switching mode locking (QML) is 2.8 W. The modulation depth is enlarged with the increase of incident pump power. At the output transmission T=20% and 10.3 W of the incident pump power, Q-switching mode-locking pulse with modulation depth about 70% is available, and the Q-switching envelope trains with the repetition rate of 40 kHz and the pulse duration of 25 ns are obtained, the average output power and the optical to optical conversion efficiency reach 2.58 W and 25%, respectively.