Femtosecond laser patterning, synthesis, defect formation, and structural modification of atomic layered materials

This article summarizes recent research on laser-based processing of two-dimensional (2D) atomic layered materials, including graphene and transition-metal dichalcogenides (TMDCs). Ultrafast lasers offer unique processing routes that take advantage of distinct interaction mechanisms with 2D materials to enable extremely localized energy deposition. Experiments have shown that ablative direct patterning of graphene by ultrafast lasers can achieve resolutions of tens of nanometers, as well as single-step pattern transfer. Ultrafast lasers also induce non-thermal excitation mechanisms that are useful for the thinning of TMDCs to tune the 2D material bandgap. Laser-assisted site-specific doping was recently demonstrated and ultrafast laser radiation under ambient air environment could be used for the direct writing of high-quality graphene patterns on insulating substrates. This article concludes with an outlook on developing further advanced laser processing with scalability, in situ monitoring strategies, and potential applications.