Controllable formation of laser-induced periodic surface structures on ZnO film by temporally shaped femtosecond laser scanning

We achieved the controllable formation of laser-induced periodic surface structures (LIPSSs) on ZnO films deposited on fused silica induced by modulated temporally shaped femtosecond (fs) laser pulses (800 nm, 50 fs, 1 kHz) through the laser scanning technique. Two-dimensional (2D) high spatial frequency LIPSSs (HSFLs) with a period from 100 to 200 nm could be flexibly modulated based on the preprocessed nanostructures with appropriate fs laser irradiation conditions (fluence, scanning speed, and pulse delay). The finite-difference time-domain (FDTD) method combined with the Drude model was employed to calculate the redistributions of electric fields, which suggested the origin of HSFL formation.