Thermopower and thermoconductance properties of zigzag edged graphene nanoribbon based thermoelectric module

The thermopower S and thermoconductance kappa properties of graphene nanoribbon based three terminal thermoelectric module are studied theoretically in two cases: with magnetic field and without magnetic field. By using the non-equilibrium Green's function method combined with the Landauer-13fittiker formula, the electric current and linear electrical conductance through the system is obtained. The S-E-F curves show a series of peaks and dips and kappa-E-F curves show plateau structures. The kappa-E-F relation is roughly linear when there is no magnetic field and is parabolic when in the quantum Hall regime because of the unique Dirac fermion in graphene. The dependence of S and kappa on the on-site energy of the terminals, sample size and Anderson disorder are investigated as well. (C) 2013 Elsevier B.V. All rights reserved.