在经典的双温模型中引入电子激发、载流子吸收等电离过程,建立了飞秒激光和晶体材料相互作用的理论模型。采用有限差分法数值模拟了在飞秒激光作用下,不同掺杂摩尔分数的Mg O∶Li Nb O3晶体内电子、晶格温度随飞秒激光脉宽、激光能量密度的变化规律。并定量分析了不同掺杂摩尔分数的Mg O∶Li Nb O3晶体材料的损伤阈值随脉宽的变化规律,以及掺杂浓度对晶体损伤阈值的影响。结果表明,在Li Nb O3晶体中掺入适量的Mg O将使载流子迁移率发生变化,进而会影响晶体的损伤阈值。在适当掺杂范围内,掺Mg O的摩尔分数越高,载流子迁移率越大,晶体的损伤阈值越高。因此,实际应用中可通过在Li Nb O3晶体中掺入适量的Mg O来提高晶体的抗损伤能力。 In the classic dual-temperature model, the introduction of electronic excitation, carrier absorption and other ionization processes, the establishment of the femtosecond laser and crystal material interaction theory model. The finite difference method was used to numerically simulate the electron and lattice temperature dependences of the femtosecond laser pulse width and laser energy density on the MgO: LiNbO3 crystal with different molar fractions under the femtosecond laser. The damage threshold of Mg O: Li Nb O 3 crystal with different doping mole fractions was quantitatively analyzed, and the influence of doping concentration on the damage threshold of the crystal was also analyzed. The results show that the incorporation of the appropriate amount of MgO in LiNbO3 crystal will change the carrier mobility, which will affect the damage threshold of the crystal. Within the appropriate doping range, the higher the mole fraction of MgO doped, the larger the carrier mobility and the higher the damage threshold of the crystal. Therefore, in practical applications, the anti-damage ability of the crystal can be improved by incorporating an appropriate amount of MgO into the LiNbO3 crystal.