Journal article
Material processing of dielectrics with temporally asymmetric shaped femtosecond laser pulses on the nanometer scale



Publication Details
Authors:
Englert, L.; Wollenhaupt, M.; Haag, L.; Sarpe-Tudoran, C.; Rethfeld, B.; Baumert, T.
Publication year:
2008
Journal:
Applied Physics A
Pages range:
749-753
Volume number:
92
Start page:
749
End page:
753
ISSN:
0947-8396

Abstract
Laser material processing of dielectrics with temporally asymmetric femtosecond laser pulses of identical fluence, spectrum, and statistical pulse duration is investigated experimentally. To that end single shot structures at the surface of fused silica as a function of fluence and pulse shape are analyzed with the help of scanning electron microscopy. Structures for the bandwidth limited pulses show the known expansion in structure size with increasing laser fluence approaching the diffraction limit, which is 1.4 mu m for the 0.5NA microscope objective used. In contrast, structures from the asymmetric pulses are remarkably stable with respect to variations in laser fluence and stay below 300 nm despite doubling the fluence. Different thresholds for surface material modification with respect to an asymmetric pulse and its time reversed counterpart are attributed to control of different ionization processes.


Research Areas


Last updated on 2019-01-11 at 16:05