Theory for the Ultrafast Ablation of Graphite Films

Harald O. Jeschke, Martin E. Garcia, K. H. Bennemann
2001 Physical Review Letters  
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
more » ... rium melting followed by fast evaporation. For low intensities above the damage threshold (> 2.0 eV/atom) ablation occurs via removal of intact graphite sheets.
doi:10.1103/physrevlett.87.015003 pmid:11461471 fatcat:7vezsh3kdvh4rdowdi3fkaycnq