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arXiv · 1903.10298

Great enhancement of strong-field ionization in femtosecond-laser subwavelength-structured fused silica

Shaohua Ye·Min Huang
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Abstract

A wavelength-degenerate pump-probe spectroscopy is used to study the ultrafast dynamics of strong-field ionization in femtosecond-laser subwavelength-structured fused silica. The comparative spectra demonstrate that femtosecond-laser subwavelength structuring always give rise to great enhancement for strong-field ionization as well as third-order nonlinear optical effects, which is the direct evidence of great local field enhancement in subwavelength apertures of fs-laser highly-excited surface. In short, the study shows the prominent subwavelength spatial effect of strong-field ionization in femtosecond-laser ablation of dielectrics, which greatly contributes to the well-known "incubation effect".

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Shaohua Ye, Min Huang. 2018-12-30. Great enhancement of strong-field ionization in femtosecond-laser subwavelength-structured fused silica. https://arxiv.org/abs/1903.10298

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