Ablation of transparent materials by high intensity and ultrashort laser pulses

The processes of nonlinear absorption is considered in transparent materials like nitride semiconductor, sapphire and others transparent dielectrics under ultrashort (fs-range) laser pulses irradiation. The ablation threshold is in multi-TW/cm 2 range. The power consumption under the ablation process is described in terms of the tunneling absorption. It is derived the ablation threshold increases as about third power of the energy bandgap of the material, in close agreement with experimental data.