Title of article :
Modeling validity of femtosecond laser breakdown in wide bandgap dielectrics
Author/Authors :
Xufeng Jing، نويسنده , , Ying Tian، نويسنده , , Junchao Zhang، نويسنده , , Shunli Chen، نويسنده , , Yunxia Jin، نويسنده , , Jianda Shao، نويسنده , , Zhengxiu Fan، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2012
Pages :
9
From page :
4741
To page :
4749
Abstract :
In order to accurately calculate the femtosecond laser breakdown threshold of wide band-gap dielectrics using the photoionization and avalanche ionization theories, the applied range of these classical methods is demonstrated quantitatively by the comparison of the calculated results with the available experimental data. It is found that these standard theories to estimate laser ablation threshold are valid when the laser pulse duration is less than about 600 fs and the laser wavelength is more than around 400 nm. Besides, we demonstrate that the multi-photon ionization of wide band-gap dielectrics is the dominant breakdown mechanism when the laser wavelength is at the region of 0.4 μm < λ < 1.3 μm. But the tunneling ionization mechanism performs a significant role when the laser wavelength is at the range of λ < 1.3 μm. Based on our calculation, we found that a valence band (VB) electron can absorb simultaneously the greatest number photons of ten in the multiphoton ionization process. Furthermore, it is revealed that the photoionization in dielectrics ionization process can provide seed electrons even at the pulse duration down to sub-10 fs.
Keywords :
Femtosecond laser breakdown
Journal title :
Applied Surface Science
Serial Year :
2012
Journal title :
Applied Surface Science
Record number :
1004838
Link To Document :
بازگشت