超短脉冲激光与介质相互作用过程中光学特性的变化

根据雪崩离化模型,分析了飞秒激光脉冲与介质材料相互作用过程中光学特性的变化规律。由于多层膜光学元件的光学特性与材料的折射率密切相关,当飞秒激光照射介质材料时,折射率会随着电场强度分布呈现不同程度的减小,从而会影响光学元件的性能。文中计算了飞秒激光照射多层膜光学元件时的透射光谱曲线,结果表明薄膜材料在发生不可逆损伤之前,光学元件的光谱特性已经发生变化。

Dielectric optical property transformation under irradiation of ultra-short pulse laser

The transformation of dielectric optical property under irradiation of ultra-short pulse laser is studied based on avalanche ionization theory.The multilayer optical characteristic depends on material′s refractive index.While under the irradiation of femtosecond laser pulse,the refractive index will decrease with the electric-field distribution,which will influence multilayer′s optical property.The spectrum is analyzed when multilayer is irradiated under femtosecond laser pulse.It is shown that the spectrum property will change before laser damage happens.