Nanograting imprinted with femtosecond-laser-induced plasmonic near-field

Summary form only given. As a promising approach to laser nanoprocessing, much interest has been focused on the self-organized, periodic surface nano structure s that are often observed in the femtosecond (fs) laser ablation experiment [1], while the ultrafast interaction poses a significant challenge to controlling the nanostructuring process and fabricating well-defined nano structures. Here we demonstrate that surface plasmon polaritons (SPPs) [3] excited with fs laser pulses can generate periodically enhanced local fields to imprint a homogeneous nanograting on gallium nitride (GaN) surface in air.