High peak power mid-infrared ablation for laser-induced periodic surface structuring on highly nonlinear zinc selenide (ZnSe)

High peak power lasers are essential tools in industrial materials processing, enabling precise control over material surfaces. Laser-Induced Periodic Surface Structuring (LIPSS) has emerged as a promising technique for surface engineering, enhancing properties such as light trapping, anti-reflectivity, and surface texturing. This research investigates the formation of LIPSS on Zinc Selenide (ZnSe) using high peak power Mid-Infrared (MIR) laser ablation, aiming to advance techniques in material modification for industrial applications. We utilized a femtosecond laser with a wavelength of 5.37 μ, pulse energy of 9 μJ, and a pulse duration of 170 fs to ablate 5 mm thick ZnSe samples. The experimental setup included a beam delivery system optimized for high-intensity MIR wavelengths, using Off-Axis Parabolic (OAP) mirrors to focus the beam. High-resolution digital microscopy and 3D surface reconstruction techniques were used post-interaction to analyze the ablation and LIPSS formation. The MIR laser ablation successfully generated periodic surface structures on ZnSe. The LIPSS exhibited high uniformity and precision, with a periodicity of approximately 1.52 times the wavelength of the incident light. The process demonstrated efficient control over surface structuring, enhancing material properties and functionalities. Subsequent studies will adjust laser parameters to tune the LIPSS patterns for specific applications. The controlled formation of periodic structures enables suitability for various high-tech manufacturing processes. This study demonstrates the successful implementation of LIPSS on ZnSe using high peak power MIR laser ablation, highlighting significant advancements in surface structuring techniques. The findings underscore the potential of MIR lasers for precise materials processing and surface engineering, paving the way for innovative applications in industrial manufacturing and material modification.