Femtosecond laser-induced periodic surface structures of copper: Experimental and modeling comparison

This study compared the experimental and numerical results of femtosecond laser-induced periodic surface structures (LIPSS) produced on copper surface. The experiments were carried out using a fiber laser of duration 300 fs, wavelength 515 nm, and a repetition rate 100 kHz. The periods of LIPSS were obtained by 2D fast Fourier transform analysis of the SEM images, and the depths were measured with an Atomic force microscope. Numerical analysis was performed using a two-dimensional two-temperature model (TTM) along with a modified Drude-critical points model, periodic energy distribution, and the phase change and explosion models for material ablation. The simulation results are in fairly good agreement with the experimental measurements.