Effects of Mid-infrared Graphene Plasmons on Photothermal Heating

We theoretically investigate the plasmonic heating of graphene-based systems under the mid-infrared laser irradiation, where periodic arrays of graphene plasmonic resonators are placed on dielectric thin films. Optical resonances are sensitive to structural parameters and the number of graphene layers. Under mid-infrared laser irradiation, the steady-state temperature gradients are calculated. We find that graphene plasmons significantly enhance the confinement of electromagnetic fields in the system and lead to a large temperature rise compared to the case without graphene. The correlations between temperature change and the optical power, laser spot, and thermal conductivity of dielectric layer in these systems are discussed. Our numerical results are in accordance with experiments.