Color nickel fabricated with femtosecond laser pulses

Colorful nickel is produced by scanning nickel films with femtosecond laser pulses. SEM images show that the surface of the colorful nickel is full of laser-induced periodic surface structures covered with nanostructures, whose period is from 480 nm to 510 nm. UV-Vis-NIR spectrophotometer analyses indicate that the reflectance of the colorful nickel decreases sharply in a wide wavelength range from 200 nm to 2 200 nm. NiO is also found in the samples studied with Raman spectra.