Nonequilibrium elastic quantum transport using plane waves

In this work, we present an \emph{ab initio} nonequilibrium electronic structure method for modeling the elastic electron transport through a nanostructure coupled to semi-infinite external electrodes and with an applied bias voltage. Our method is based on the scheme presented in Ref.\,[1], where the coherent quantum transport is calculated by means of the \emph{exact} scattering states of the system obtained using plane waves and for zero applied bias voltage. In the case of a finite bias voltage, the electronic system is in a nonequilibrium situation, and the problem needs to be solved self-consistently. Here, we present an approach to obtain the self-consistent charge density and potential of the system, which are then employed in the calculation of the nonequilibrium transmission coefficient and conductance. As an illustration, results for a model system made up of a di-thiol-benzene (DBT) molecule connected by two Cu wires are provided. [1] A. Garcia-Lekue and L.W. Wang, Phys. Rev. B. {\bf 74}, 245404 (2006).