Molecular dynamic simulation on the graphitization of amorphous carbon induced by laser irradiation

In this work, we use MD simulation to model the graphitization process of a-C film by laser heating in heat-assisted magnetic recording. The amorphous carbon is heated to 800K and cooled down to room temperature within nanosecond. During the laser heating and cooling process, the rate of the sp2-hybridized atoms rate keeps increasing from 16% to 68%. The trend of sp2 hybridized atoms rate is analogous with the pressure of the system. The pressure is an essential ingredient in the graphitization of amorphous carbon.