Femtosecond laser-induced nanostructure formation in Sb2Te3

We report femtosecond laser-induced nanotracks in highly absorbing Sb2Te3. Groups of nanotracks are observed with widths ∼50 nm and periodicity ∼130 nm, their area of coverage extending with the increase of laser fluence. We demonstrate that under a narrow range of laser fluences and laser irradiation times, long highly aligned nanotracks can be formed in Sb2Te3. The results suggest a promising avenue for laser nanostructuring of chalcogenide thermoelectrics, with implications for high efficiency thermoelectric energy conversion.