Femtosecond laser-induced large area of periodic structures on chalcogenide glass via twice laser direct-writing scanning process

摘要

We presented a theoretical and experimental study for the evolution of femtosecond laser direct-writing induced large area of periodic surface structures on As2S3 glass. The laser direct-writing induced large area of low spatial frequency LIPSS (LSFL) structures can be fabricated with the overlap rate increases from 65% to 80%. The evolution process can be defined by the competition between the laser fluence and pulse overlap rate. What is more important is that, based on secondary femtosecond laser scanning process, the interaction between the initial LSFL structures induced by the first scanning and the laser pulse of the second scanning process can induce local field enhancement effect, which can directly split the surface periodic structures of LSFL. Such new subsequent high spatial frequency LIPSS (HSFL) fabrication process is quite different from the traditional multipulse induced HSFL and can be used to fabricate large-area HSFL structures.