Electron and phonon transport in twisted graphene nanoribbons

We theoretically study the electronic, thermal and thermoelectric properties of graphene nanoribbons under torsional deformations. The modelling follows a nonequilibrium Green's function approach in the ballistic transport regime, describing the electrical and phononic properties through ab initio density functional theory and empirical interatomic potentials, respectively. We consider two different types of deformations, a continuous twist of a given angle applied to the nanoribbon, and two consecutive twists applied in opposite angular directions. The numerical results are carefully analysed in terms of spatially-resolved electron eigenchannels, polarization-dependent phonon transmission and thermoelectric figure-of-merit.