Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany.
Phys Chem Chem Phys. 2013 Oct 14;15(38):15845-9. doi: 10.1039/c3cp51307f. Epub 2013 Sep 3.
We compare the conductance of an interacting ring with six lattice sites threaded by flux π in a two terminal setup with the conductance of the corresponding Kohn-Sham particles. Based on symmetry considerations we can show that even within (lattice) Density Functional Theory employing the exact Kohn-Sham exchange-correlation functional the conductance of the Kohn-Sham particles is exactly zero, while the conductance of the physical system is close to the unitary limit. We provide a clear demonstration that the linear conductance is not given by the conductance of the Kohn-Sham particles. We show that this fundamental problem might be solved by extending the standard DFT scheme.
我们将通过一个两端装置，对比由通量π穿过的具有六个晶格位置的相互作用环的电导，与相应的 Kohn-Sham 粒子的电导。基于对称考虑，我们可以表明，即使在（晶格）密度泛函理论中采用精确的 Kohn-Sham 交换关联泛函，Kohn-Sham 粒子的电导也严格为零，而物理系统的电导则接近于幺正极限。我们清楚地证明，线性电导不是由 Kohn-Sham 粒子的电导给出的。我们表明，通过扩展标准的 DFT 方案，可以解决这个基本问题。
