Thermoelectric Properties of Graphene Like Nanotube Structure Due to Next-to-nearest Neighbor Hopping Amplitude

Abstract

We have addressed the density of states and thermoelectric properties of doped graphene like nanotubes for both zigzag and armchair types in the context of tight binding model hamiltonian. The effects of next nearest neighbor hopping amplitude for electrons and gap parameter on thermal conductivity, Seebeck coefficient and figure of merit have been investigated. Green’s function approach has been implemented to find the behavior of transport coefficients of nanotube within linear response theory. We have found the temperature dependence of thermoelectric properties for different values of the gap parameter and tube diameter in the presence of next nearest neighbor hopping integral. The results of electrical conductivity show the increase of diameter leads to increase thermal conductivity of armchair nanotubes. However the variation of tube diameter has no remarkable effect on thermal conductivity of zigzag nanotube. Also the increase of chemical potential reduces the conductivity of zigzag nanotube. Moreover the temperature behavior of the other thermoelectric properties, i.e. figure of merit and Seebeck coefficient, have been addressed for both types of nanotubes in details.