Surface nanostructuring by using circularly polarized GHz burst mode femtosecond laser pulses

Recently, there has been growing interest in GHz burst mode femtosecond laser pulses, which are characterized by a series of pulse (intra-pulse) trains with an extremely short pulse-to-pulse interval of several hundred picoseconds. The GHz burst is expected to be a superior tool to achieve high quality, high speed, and high efficiency as compared to the conventional irradiation scheme of fs laser pulses (single-pulse mode). We have revealed that linearly polarized GHz bursts can create lattice-like, 2D laser-induced periodic surface structures (LIPSS), exhibiting distinct geometries from the stripe-patterned 1D-LIPSS formed by the single-pulse mode fs laser pulse irradiation. It’s known that the circularly polarized single-pulse mode fs laser pulses can produce dot-patterned LIPSS on various solid materials. This study explores the potential of creating novel surface nanostructures by using the circularly polarized GHz burst mode fs laser processing and investigate their functionalities.