Dipartimento di Fisica, Università di Roma Tor Vergata, Rome, Italy.
Phys Rev Lett. 2011 Nov 18;107(21):216401. doi: 10.1103/PhysRevLett.107.216401. Epub 2011 Nov 14.
We demonstrate that the zero-temperature conductance of the Anderson model can be calculated within the Landauer formalism combined with static density-functional theory. The proposed approximate functional is based on finite-temperature density-functional theory and yields the exact Kohn-Sham potential at the particle-hole symmetric point. Furthermore, in the limit of zero temperature it correctly exhibits a derivative discontinuity which is shown to be essential to reproduce the conductance plateau. On the other hand, at the Kondo temperature the exact Kohn-Sham conductance overestimates the real one by an order of magnitude. To understand the failure of density-functional theory, we resort to its time-dependent version and conclude that the suppression of the Kondo resonance must be attributed to dynamical exchange-correlation corrections.
我们证明了安德森模型的零温电导可以在包含静态密度泛函理论的朗道规范下进行计算。所提出的近似泛函基于有限温度密度泛函理论,并在粒子-空穴对称点给出了精确的库恩-肖姆势。此外,在零温极限下,它正确地表现出导数不连续,这对于再现电导平台是至关重要的。另一方面,在近藤温度下,精确的库恩-肖姆电导率比实际电导率高出一个数量级。为了理解密度泛函理论的失效,我们求助于它的时间相关版本,并得出结论,近藤共振的抑制必须归因于动态交换相关修正。