Kondo physics of the Anderson impurity model by distributional exact diagonalization

A recently proposed density functional approach for steady-state transport through nanoscale systems (called i-DFT) is used to investigate junctions which are asymmetrically coupled to the leads and biased with asymmetric voltage drops. In the latter case, the system can simply be transformed to a physically equivalent one with symmetric voltage drop by a total energy shift of the entire system. For the former case, known exchange correlation gate and bias functionals have to be generalized to take into account the asymmetric coupling to the leads. We show how differential conductance spectra of the constant interaction model evolve with increasing asymmetry of both voltage drops and coupling to the leads.

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“…For comparison, equilibrium spectral functions from numerical renormalization group (NRG) calculations of Ref. [38] are shown.…”

Section: Resultsmentioning

confidence: 99%

Exchange-correlation functionals of i-DFT for asymmetrically coupled leads

Kurth

Jacob

2018

Eur. Phys. J. B

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“…Comparison of Anderson model spectra calculated from i-DFT via Eq. (10) with NRG (taken from Ref [33]…”

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confidence: 99%

Many-Body Spectral Functions from Steady State Density Functional Theory

Jacob

Kurth

2018

Nano Lett.

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We propose a scheme to extract the many-body spectral function of an interacting many-electron system from an equilibrium density functional theory (DFT) calculation. To this end we devise an ideal scanning tunneling microscope (STM) setup and employ the recently proposed steady-state DFT formalism (i-DFT) which allows one to calculate the steady current through a nanoscopic region coupled to two biased electrodes. In our setup, one of the electrodes serves as a probe ("STM tip"), which is weakly coupled to the system we want to measure. In the ideal STM limit of vanishing coupling to the tip, the system is restored to quasi-equilibrium and the normalized differential conductance yields the exact equilibrium many-body spectral function. Calculating this quantity from i-DFT, we derive an exact relation expressing the interacting spectral function in terms of the Kohn-Sham one. As illustrative examples, we apply our scheme to calculate the spectral functions of two nontrivial model systems, namely the single Anderson impurity model and the Constant Interaction Model.

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“…[31] for the two-terminal case, i.e., for γ T = 0, which has been shown to be accurate in a wide range of temperatures and charging energy. For V T,xc we propose [40,41]. The Kondo temperature is ΘK /γ ≈ 0.066.…”

Section: I-dft Potentials For the Anderson Modelmentioning

confidence: 99%

“…2. Equilibrium i-DFT spectral functions A(ω) of the SIAM at ph symmetry for U/γ = 5 for various temperatures compared with NRG results [40,41]. The Kondo temperature is ΘK /γ ≈ 0.066.…”

Section: I-dft Potentials For the Anderson Modelmentioning

confidence: 99%

Nonequilibrium spectral functions from multiterminal steady-state density functional theory

et al. 2019

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Multi-terminal transport setups allow to realize more complex measurements and functionalities (e.g., transistors) of nanoscale systems than the simple two-terminal arrangement. Here the steady-state density functional formalism (i-DFT) for the description of transport through nanoscale junctions with an arbitrary number of leads is developed. In a three-terminal setup and in the ideal STM limit where one of the electrodes (the "STM tip") is effectively decoupled from the junction, the formalism allows to extract its non-equilibrium spectral function (at arbitrary temperature) while a bias is applied between the other two electrodes. Multi-terminal i-DFT is shown to be capable of describing the splitting of the Kondo resonance in an Anderson impurity in the presence of an applied bias voltage, as predicted by numerically exact many-body approaches. arXiv:1905.13070v1 [cond-mat.mes-hall]

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Kondo physics of the Anderson impurity model by distributional exact diagonalization

Cited by 9 publications

References 50 publications

Exchange-correlation functionals of i-DFT for asymmetrically coupled leads

Exchange-correlation functionals of i-DFT for asymmetrically coupled leads

Many-Body Spectral Functions from Steady State Density Functional Theory

Nonequilibrium spectral functions from multiterminal steady-state density functional theory

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