Electron transport of carbon atoms sequence in two-band model

Abstract

The electron quantum transport of a linear chain of carbon atoms between two semi-infinite carbon leads has been investigated using the nearest neighbor tight-binding approximation of the Harrison’s model and the Landauer–Buttiker formalism. The analytical results of band structure of the chain and the self-energies due to leads have been obtained by solving the discretized form of the Schrodinger’s equation. Based on the formulation of the multi-atomic orbital approach in the Harrison’s model, the electronic band structure, density of states, electron transmission probability and current–voltage curves are discussed. The results show that the $$sp_x$$ -hybridized carbon chain with equivalent double bonds exhibits a conductive behavior. Studying the effect of length increase (the number of atoms) on the density of states and transmission probability of carbon chains, an evident even–odd behavior is observed at the Fermi level. Finally, it is found that as the temperatures of the leads increase, the shape of the sharp step of current–voltage curves smoothens.