镱、钠共掺的氟化钙晶体在1050nm的可饱和吸收作用

通过在稳定连续波运转的Yb:YAG激光器中插入不同掺杂浓度的新型钠、镱共掺的氟化钙晶体的对比性实验,证明了镱、钠共掺的氟化钙晶体在1050nm具有明显的可饱和吸收作用,从而解释了该晶体作为增益介质在该波段总是趋于自调Q运转的原因.Yb3+离子是该晶体可饱和吸收作用的主要因素,但是共掺入适当的Na离子可以明显改善晶体的调Q效果.优化共掺镱、钠离子的浓度和比例后的氟化钙晶体能够作为1050nm波段激光器的被动Q开关.

The saturable absorption of Yb3+/Na+ codoped CaF2 crystals at 1050nm has been demonstrated by comparative experiments by inserting the novel Yb3+, Na+:CaF2 crystal with different doping concentrations into a Yb:YAG laser in stable continuous wave operation, which is the cause for the crystals working as the gain material to tend to self-Q-switching at 1050 nm. The results show that the dominative element is Yb3+ rather than Na+ for saturable absorption action of the crystals. However, the effect of Q-switching by codoping Na+ into the CaF2 crystals can be greatly improved so that the Yb3+, Na+:CaF2 crystals with optimum concentration and doping ratio can be used as a Q-switching element at 1050 nm.