Quantum Back Action from Photo-Excited Electrons in Graphene Layers on Hybridization of Radiative and Evanescent Fields*

We demonstrate the quantum back action from photo-excited Dirac electrons in two Coulomb-coupled graphene layers on the hybridization of radiative and evanescent field modes. The induced polarization fields in graphene layers significantly modify an incident surface-plasmon-polariton wave. This results in a high sensitivity to local dielectric environments and provides a unique tool for detecting and probing molecules selectively bound to carbons. Both optical-absorption spectra and scattering matrices of the surface-plasmon-polariton wave are calculated for frequencies close to the surface-plasmon resonance with various interaction strengths between two layers and the surface of a conducting substrate.