In this paper, a novel 2D ternary chalcogenide Ta2NiSe5 is fabricated into a saturable absorber by using the liquid phase exfoliation (LPE) method and successfully applied to the passive Q-switching experiment of Tm:YAP all-solid-state laser at 2 µm. The nonlinear optical absorption (NOA) properties of Ta2NiSe5 at 2 µm was measured by using an open-aperture Z-scan method, showing saturation fluence and modulation depth of 400 µJ/cm2 and 24%, respectively. By using Ta2NiSe5 as saturable absorber, the shortest pulse width of 740 ns and maximum repetition frequency of 71 kHz are obtained, respectively. This results prove that the Ta2NiSe5 is an excellent saturable absorber to achieve passively Q-switched laser at 2 µm, for the first time to the best of our knowledge.

中文翻译：

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基于 Ta2NiSe5 可饱和吸收体的 2 µm 被动调Q全固态激光器

在本文中，采用液相剥离（LPE）方法将新型二维三元硫族化物 Ta2NiSe5 制成可饱和吸收体，并成功应用于 2 µm Tm:YAP 全固态激光器的被动调Q实验。Ta2NiSe5 在 2 µm 处的非线性光吸收 (NOA) 特性是通过使用开放孔径 Z 扫描方法测量的，显示饱和注量和调制深度分别为 400 µJ/cm2 和 24%。通过使用Ta2NiSe5作为饱和吸收体，分别获得了740 ns的最短脉冲宽度和71 kHz的最大重复频率。这一结果证明，据我们所知，Ta2NiSe5 是一种出色的可饱和吸收体，可实现 2 µm 的被动调Q激光。