Optical and Wetting Properties of Femtosecond Laser Nanostructured Materials
We modify optical and wetting properties of solids using a femtosecond laser surface nanostructuring technique. We demonstrate that this technique allows creating black and color metals. Absorptance of black titanium created in our study is measured to be about 90-97% over a broad wavelength range from the ultraviolet to infrared. Moreover, our technique can be also used for modifying wetting properties of solids. Here, we create a novel surface structure that transforms regular silicon to superwicking. This surface structure makes water run vertically uphill in a gravity defying way. Our study of the liquid motion shows that the extraordinarily strong self-propelling motion of water is due to a capillary effect from the surface structures we created.
A.Y. Vorobyev and C. L. Guo, "Optical and Wetting Properties of Femtosecond Laser Nanostructured Materials", Journal of Nano Research, Vol. 14, pp. 57-67, 2011