Metal colorization with femtosecond laser pulses

Abstract

Recently, using a femtosecond laser surface structuring technique we turned highly reflective metals to highly absorptive, creating the so-called "black metals". In this study, we made an even more significant advancement. Here, we demonstrate that our femtosecond laser structuring technique not only allows us to create black metals but also gray and even color metals. We show that our technique essentially provides a controllable modification of optical properties of metals from the UV to THz spectral range via surface structuring on the nano-, micro-, and submillimeter-scales.