Nonequilibrium Anderson model made simple with density functional theory

S. Kurth; G. Stefanucci

doi:10.1103/physrevb.94.241103

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arXiv · 1605.09330

Nonequilibrium Anderson model made simple with density functional theory

S. Kurth·G. Stefanucci

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Abstract

The single-impurity Anderson model is studied within the i-DFT framework, a recently proposed extension of density functional theory (DFT) for the description of electron transport in the steady state. i-DFT is designed to give both the steady current and density at the impurity, and it requires the knowledge of the exchange-correlation (xc) bias and on-site potential (gate). In this work we construct an approximation for both quantities which is accurate in a wide range of temperatures, gates and biases, thus providing a simple and unifying framework to calculate the differential conductance at negligible computational cost in different regimes. Our results mark a substantial advance for DFT and may inform the construction of functionals applicable to other correlated systems.

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S. Kurth, G. Stefanucci. 2016-05-30. Nonequilibrium Anderson model made simple with density functional theory. https://doi.org/10.1103/physrevb.94.241103

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