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Theory for the ultrafast ablation of graphite films

H. O. Jeschke·M. E. Garcia·K. H. Bennemann
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Abstract

The physical mechanisms for damage formation in graphite films induced by femtosecond laser pulses are analyzed using a microscopic electronic theory. We describe the nonequilibrium dynamics of electrons and lattice by performing molecular dynamics simulations on time-dependent potential energy surfaces. We show that graphite has the unique property of exhibiting two distinct laser induced structural instabilities. For high absorbed energies (> 3.3 eV/atom) we find nonequilibrium melting followed by fast evaporation. For low intensities above the damage threshold (> 2.0 eV/atom) ablation occurs via removal of intact graphite sheets.

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H. O. Jeschke, M. E. Garcia, K. H. Bennemann. 2001-03-05. Theory for the ultrafast ablation of graphite films. https://doi.org/10.1103/physrevlett.87.015003

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