Micro-structuring, ablation, and defect generation in graphene with femtosecond pulses

Femtosecond micromachining offers a contact-free and mask-less technique for material patterning. Femtosecond pulse irradiation of single layer graphene by low energy pulses around 12 nJ over a 15 second illumination period is studied. The ablated graphene holes are surrounded by a radially symmetric region characterized by generated defects, whose extension can be modified based on the laser fluence. The femtosecond induced structural modifications can be attractive for graphene or carbon-based device fabrication as well as sensor and transistor applications, where regions of varying carrier concentrations and different electrical, optical, or physical properties are desired.