为了获得可调谐长波红外激光输出，本文设计了一种基于ZnGeP₂（ZGP）温度调谐的长波红外光参量振荡器。采用中心波长为2097 nm的Ho:YAG激光器泵浦不同相位匹配角的ZGP晶体，通过改变晶体工作温度来研究ZnGeP₂光参量振荡器(ZGP-OPO)的温度调谐特性。在15~30 °C温度范围内，实现了7.53~8.77 μm分段可调谐长波激光输出，总调谐宽度为1.24 μm。整个调谐范围内，输出功率大于1.503 W，当闲频光波长为8.77 μm时，输出功率为1.503 W，斜率效率和光光转换效率分别为12.19%和6.53%。实验结果表明，ZGP温度调谐是实现连续可调谐长波红外激光输出的有效技术途径。本实验研究在可调谐长波固体激光器工程化领域具有潜在的应用价值。

ZnGeP₂ (ZGP) crystals have attracted tremendous attention for their applications as frequency conversion devices. Nevertheless, the existence of native point defects, including at the surface and in the bulk, lowers their laser-induced damage threshold by increasing their absorption and forming starting points of the damage, limiting their applications. Here, native point defects in a ZGP crystal are fully studied by the combination of high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and optical measurements. The atomic structures of the native point defects of the Zn vacancy, P vacancy, and Ge-Zn antisite were directly obtained through an HAADF-STEM, and proved by photoluminescence (PL) spectra at 77 K. The carrier dynamics of these defects are further studied by ultrafast pump-probe spectroscopy, and the decay lifetimes of 180.49, 346.73, and 322.82 ps are attributed to the donor V_p⁺ → valence band maximum (VBM) recombination, donor Ge_Zn⁺ → VBM recombination, and donor–acceptor pair recombination of V_p⁺ → V_Zn^-, respectively, which further confirms the assignment of the electron transitions. The diagrams for the energy bands and excited electron dynamics are established based on these ultrahigh spatial and temporal results. Our work is helpful for understanding the interaction mechanism between a ZGP crystal and ultrafast laser, doing good to the ZGP crystal growth and device fabrication.