Additivity of kinetic and potential energy contributions in modification of graphene supported on SiO₂

The damage production induced by MeV highly charged ions (HCI) irradiations in graphene supported on a SiO₂ substrate is investigated using molecular dynamics method. We get results in agreement with our recent experiments. We find that the electronic energy loss and potential energy deposition have similar effects on the defects creation in SiO₂ substrate-supported graphene and both mechanisms of energy deposition seem to contribute in an additive way. The influences of the energy deposition depth and radius are studied. Only the energy deposited below the surface within 2.5 nm will induce the damage in graphene. Hence, the HCI can be a powerful tool to induce defects in graphene without causing deep damage of the substrate. When charge of incident Xe^q+ is above 30, a nanopore is formed and the size of nanopore in graphene can be controlled by changing the incident charge state.