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.
@article{arxiv.cond-mat/0103118,
title = {Theory for the ultrafast ablation of graphite films},
author = {H. O. Jeschke and M. E. Garcia and K. H. Bennemann},
journal= {arXiv preprint arXiv:cond-mat/0103118},
year = {2007}
}
Comments
5 pages RevTeX, 3 PostScript figures, submitted to Phys. Rev