We report on the fabrication and evolution of metal nanowires with a length of 5 μm and a diameter of 100 nm which were successfully photo-converted from scale-like copper micro-flakes, dispersed in an alcohol solution, under ultrashort pulse laser radiation and a subsequent aging treatment. The dependence of the observed copper nanowires on the conditions of the laser irradiation and aging treatment, and the influence of the surrounding solvent were also investigated. The photoinduced morphology changes are unusual and their optical properties are striking. These previously unknown metal nanowires have a very high aspect ratio, and are created by nuclear growth mechanisms.

Keywords: Morphology control, Copper nanowires, Femtosecond laser.