title: Steady-State Density Functional Theory for Finite Bias Conductances.
abstract: In the framework of density functional theory, a formalism to describe electronic transport in the steady state is proposed which uses the density on the junction and the steady current as basic variables. We prove that, in a finite window around zero bias, there is a one-to-one map between the basic variables and both local potential on as well as bias across the junction. The resulting Kohn-Sham system features two exchange-correlation (xc) potentials, a local xc potential, and an xc contribution to the bias. For weakly coupled junctions the xc potentials exhibit steps in the density-current plane which are shown to be crucial to describe the Coulomb blockade diamonds. At small currents these steps emerge as the equilibrium xc discontinuity bifurcates. The formalism is applied to a model benzene junction, finding perfect agreement with the orthodox theory of Coulomb blockade.
authors.affiliation: Dipartimento di Fisica and European Theoretical Spectroscopy Facility (ETSF), Università di Roma Tor Vergata , Via della Ricerca Scientifica 1, 00133 Rome, Italy.|INFN, Laboratori Nazionali di Frascati, Via E. Fermi 40, 00044 Frascati, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Stefanucci
authors.affiliation: Nano-Bio Spectroscopy Group and European Theoretical Spectroscopy Facility (ETSF), Dpto. de Física de Materiales, Universidad del País Vasco UPV/EHU , Av. Tolosa 72, E-20018 San Sebastián, Spain.|IKERBASQUE, Basque Foundation for Science, Maria Diaz de Haro 3, E-48013 Bilbao, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Kurth
keywords: Coulomb blockade diamonds; Density functional theory (DFT); exchange-correlation bias; quantum transport