Femtosecond laser processed non-additive broad-band/selective absorptive coatings for a range of military and civilian applications

S. Singh
University of Rochester, United States

Keywords: Broadband absorber, selective absorber, anti-reflective coating, enhanced transmittance,super-hydrophobic, superhydrophillic

Femtosecond laser processing developed and pioneered by University of Rochester (UoR) is a direct surface processing technology that alters a thin layer of a range of materials including metals, semiconductors and ceramics to perfectly black or decorate with particular structural color.1 Femtosecond laser processing technology can dramatically alters wetting properties of surface to make it either superhydrophobic or superhydrophilic/ super-wicking. Superhydrophobicity is so strong that water drop bounces as ping-pong ball on concrete surface. Similarly, the superwicking property is so strong that water uphilles against gravity with unprecedented high speed. These technologies developed at UoR attained wide media coverage including four times in NY times.2 In contrast to conventional physical and chemical coating technology, proposed approach has number of advantages including (i) retaining intrinsic thermal and elastic properties of metals, (ii) ambient based single step processing, (iii) easily scalable for large-scale production, (iv) can be applied to treat surface of any material in any shape, size and geometry. Convectional, coating and paints add extra mass to the material that is critical for space applications.