Even–odd effect of the thermoelectric information for zigzag phosphorene nanoribbons under an electric field

Abstract

We study the thermoelectric properties of zigzag-edge phosphorene nanoribbon with N chains (N-ZPNR) under a perpendicular electric field (PEF). By adopting the tight-binding Hamiltonian combined with the nonequilibrium Green’s function method, it is demonstrated that the maximum value of the Seebeck coefficients for both 40- and 41-ZPNRs can reach 4 mV/K. Interestingly, there is an even–odd effect on the thermoelectric properties when a PEF is applied, which originates from the structure symmetry of N-ZPNR and can result in different behavior of edge states for even and odd cases. Specifically, the increasement induced by the external field of the Seebeck coefficient for 41-ZPNR with odd number of chains is much more pronounced than that for 40-ZPNR with even number. Moreover, the introduction of the Anderson disorder to the system can suppress the transmission but enhance the Seebeck coefficients for both even and odd cases.