The nonlinear absorption properties of GaAs were measured at 1.06 and 1.34 µm by the open aperture Z-scan technique in this paper. Based on a neodymium doped calcium niobium gallium garnet (Nd:CNGG) disordered crystal grown by the Czochralski method, passively Q-switched lasers with the conventional GaAs wafer as the saturable absorber were demonstrated, operating on the transitions of ⁴F_3/2 → ²I_11/2 and ⁴F_3/2 → ²I_13/2. For the ⁴F_3/2 → ²I_11/2 transition, the laser operated at 1063 nm with a pulse duration of 546 ns and a repetition rate of 98.5 kHz. While for the ⁴F_3/2 → ²I_13/2 transition operating at 1340 nm, the minimum pulse width was 499.6 ns with the pulse repetition rate of 110.7 kHz.

中文翻译：

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GaAs调Q Nd：CNGG激光器：工作在⁴ F _3/2 → ² I _11/2和⁴ F _3/2 → ² I _13/2跃迁

本文通过开孔Z扫描技术测量了GaAs的非线性吸收特性，分别为1.06和1.34 µm。基于通过Czochralski方法生长的掺钕铌钙镓镓石榴石（Nd：CNGG）无序晶体，证明了采用传统GaAs晶片作为可饱和吸收体的被动调Q激光器，其在⁴ F _3/2 →跃迁下工作。² I _11/2和⁴ F _3/2 → ² I _13/2。对于⁴ F _3/2 → ² I _11/2过渡时，激光器在1063 nm处工作，脉冲持续时间为546 ns，重复频率为98.5 kHz。对于工作在1340 nm的⁴ F _3/2 → ² I _13/2跃迁，最小脉冲宽度为499.6 ns，脉冲重复率为110.7 kHz。