LIPSS formation on Ni surface using mixed near-infrared laser beam harmonics

Generation of laser-induced periodic surface structures (LIPSS) is investigated with femtosecond laser pulses with 1030nm wavelength and its second and its harmonics. The second (λ 2 ω = 515 nm ) and third harmonics (λ 3 ω = 343 nm ) beams in addition to their combination were utilized to control the period of the LIPSS on a Ni surface. The resulting periodicity of the formed structures was ∼ 0.42 μm , 0.22 μm , and 0.33 μm respectively for the second harmonic beam, third harmonic beam, and their combination. This method demonstrates a direct way to control the periodicities on a metal target by employing an individual laser beam wavelength to induce a variable range of LIPSS periods.