We present in‐situ Raman measurements of laser‐induced oxidation in exfoliated single‐layer graphene. By using high‐power laser irradiation, we can selectively and in a controlled way initiate the oxidation process and investigate its evolution over time. Our results show that the laser‐induced oxidation process is divided into two separate stages, namely tensile strain due to heating and subsequent p‐type doping due to oxygen binding. We discuss the temporal evolution of the D/G‐mode ratio during oxidation and explain the unexpected steady decrease of the defect‐induced D mode at long irradiation times. Our results provide a deeper understanding of the oxidation process in single‐layer graphene and demonstrate the possibility of sub’m patterning of graphene by an optical method.
Evolution of the D/G‐mode ratio in laser‐irradiated single‐layer graphene, as well as a representative Raman spectrum.