Testing the Standard Approach for Density-Functional Transport Calculations

Conductance across a single molecular junction can be calculated via the Landauer formalism. This is the standard approach for density-functional theory calculations of transport, but it requires extremely accurate Kohn-Sham potentials that can only be achieved under certain conditions using accurate functionals. Recent work has shown an example where the standard approach works remarkably well for a site model [1, 2]. In this work, we test the standard approach for one dimension in real space where we can extract numerically exact potentials using density-matrix renormalization group [3]. \\[4pt] [1] J. P. Bergfield, Z.-F. Liu, K. Burke, and C. A. Stafford, ``Bethe ansatz approach to the kondo effect within density-functional theory,'' Phys. Rev. Lett., 108, 066801 (2012).\\[0pt] [2] Z.-F. Liu, J. P. Bergfield, K. Burke, and C. A. Stafford, ``Accuracy of density functionals for molecular electronics: the anderson junction,'' Phys. Rev. B (2012).\\[0pt] [3] E. M. Stoudenmire, L. O. Wagner, S. R. White, and K. Burke, ``One-dimensional continuum electronic structure with the density-matrix renormalization group and its implications for density-functional theory,'' Phys. Rev. Lett., 109, 056402 (2012).