The Equation of Electron Diffusion in the Momentum Space in Graphene

Small fluctuations of the electron system from the equilibrium state due to electronacoustic phonon intraband, intravalley random scatterings in graphene have been analyzed. In the linearization approximation of the Boltzmann transport equation a second-order linear partial differential equation for the time and energy dependences of the symmetric component of the fluctuations of the electron distribution function has been obtained. This equation can be considered as the Fokker-Planck equation in the momentum space, which describes the chaotic movement of the electron along the energy axis, i.e. the electron diffusion in the momentum space.