Nanoscale ablation on patterned diamondlike carbon film with femtosecond laser pulses

The authors have studied the origin of nanostructure formation on diamondlike carbon film in femtosecond laser ablation at low fluence. Using the thin film target patterned with submicrometer-size stripes, they have observed that the nanostructure starts to be formed on the crest of stripes along the direction perpendicular to the laser polarization. The experimental results have shown that nanoscale ablation for the nanostructuring would preferentially be initiated by the enhancement of localized electric field on the stripe surface with high curvature.