▎ 摘　　要

In this work, we present an observation of laser induced periodic surface structures (LIPSS) on graphene. LIPSS on other materials have been observed for nearly 50 years, but until now, not on graphene. Our findings for LIPSS on multi-layer graphene were consistent with previous reports of LIPSS on other materials, thus classifying them as high spatial frequency LIPSS. LIPSS on multi-layer graphene were generated in an air environment by a linearly polarized femtosecond laser with excitation wavelength lambda of 840 nm, pulse duration tau of similar to 150 fs, and a fluence F of similar to 4.3-4.4 mJ/cm(2). The observed LIPSS were perpendicular to the laser polarization and had dimensions of width w of similar to 30-40 nm and length l of similar to 0.5-1.5 mu m, and spatial periods K of similar to 70-100 nm (similar to lambda/8-lambda/12), amongst the smallest of spatial periods reported for LIPSS on other materials. The spatial period and width of the LIPSS were shown to decrease for an increased number of laser shots. The experimental results support the leading theory behind high spatial frequency LIPSS formation, implying the involvement of surface plasmon polaritons. This work demonstrates a new way to pattern multi-layer graphene in a controllable manner, promising for a variety of emerging graphene/LIPSS applications. (C) 2014 AIP Publishing LLC.