【摘要】 基于固体的能带理论和能量守恒原理建立了一个描述激光与非金属材料作用时载流子随时间空间变化的理论模型。讨论了材料的破坏阈值、烧蚀深度与激光脉宽、波长和强度之间的关系,同时也讨论了破坏阈值、烧蚀深度与材料禁带宽度等特性之间的关系。讨论了多光子电离、隧道电离和雪崩电离在激光对材料破坏过程中的不同地位,理论结果表明,光电离在超短脉冲激光对非金属材料破坏过程中对破坏阈值的影响最大。更多还原

【Abstract】 A theoretical model based on solid state energy band theory and energy conservation is developed which can describe temporal and spatial distribution of carriers in nonmetal materials during laser-induced damage.The relation between damage threshold,ablation depth and laser pulse duration,wavelength,energy fluence is studied with the model.The effects of the electronic properties of material on damage threshold and ablation depth are also discussed.The respective roles of multi-photon ionization,tunnel ionization,and avalanche ionization in laser induced damage are examined,and it is found that photo-ionization is always the most important role in the nonmetal materials during ultra-short laser induced damage.更多还原