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Periodic structure of metals with femtosecond laser ablation

The laser ablation for Cu, Al, Fe, Zn, Ni, Pb, and Mo by short pulse laser (800 nm wavelength, 100 fs pulse duration, 1 kHz repetition rate) in air was studied. The craters produced by laser ablation were measured with a scanning electron microscope (SEM) and an atomic forced microscope (AFM). Some possible physical mechanisms in relation to the process of the periodic structure are discussed.