TY - GEN A1 - Reif, Jürgen A1 - Varlamova, Olga A1 - Uhlig, Sebastian A1 - Varlamov, Sergej A1 - Bestehorn, Michael T1 - On the physics of self-organized nanostructure formation upon femtosecond laser ablation T2 - Applied Physics A N2 - We present new results on femtosecond LIPSS on silicon, fostering the dynamic model of self-organized structure formation. The first set of experiments demonstrates LIPSS formation by irradiation with a femtosecond white light continuum. The ripples are, as usual, perpendicular to the light polarization with a fluence-dependent wavelength between 500 and 700 nm. At higher dose (fluence × number of shots), the LIPSS turn to much coarser structures. The second set of experiments displays the dose dependence of pattern evolution at about threshold fluence. In contrast to the general case of multi-pulse LIPSS, where a strong dependence of the structures on the laser polarization is observed, single-shot exposition of silicon at about the ablation threshold results in a concentric pattern of very regular sub-wavelength ripples following the oval shape of the irradiated spot, without any reference to the laser polarization. When increasing the number of pulses, the usual, typical ripples develop and then coalesce into broader perpendicular structures, interlaced with remnants of the first, finer ripples. Y1 - 2016 UR - https://opus4.kobv.de/opus4-UBICO/frontdoor/index/index/docId/17081 UR - http://link.springer.com/article/10.1007/s00339-014-8339-x SN - 0947-8396 SN - 1432-0630 VL - 117 IS - 1 SP - 179 EP - 184 ER -