Graphene susceptibility in Holstein model

We study the effects of the electron-phonon interaction on the temperature dependence of the orbital magnetic susceptibility of monolayer graphene. We use the linear response theory and Green's function formalism within the Holstein Hamiltonian model. The results show that the effects of the electron-phonon interaction on the susceptibility of graphene sheet have different behaviors in two temperature regions. In the low temperature region, susceptibility increases when the electron-phonon coupling strength increases. On the other hand, the susceptibility reduces with increasing the electron-phonon coupling strength in the high temperature region.