Kondo effect in the Kohn-Sham conductance of multiple levels quantum dots

Abstract

At zero temperature, the Landauer formalism combined with static density functional theory is able to correctly reproduce the Kondo plateau in the conductance of the Anderson impurity model provided that an exchange-correlation potential is used which correctly exhibits steps at integer occupation. Here we extend this recent finding to multi-level quantum dots described by the constant-interaction model. We derive the exact exchange-correlation potential in this model for the isolated dot and deduce an accurate approximation for the case when the dot is weakly coupled to two leads. We show that at zero temperature and for non-degenerate levels in the dot we correctly obtain the conductance plateau for any odd number of electrons on the dot. We also analyze the case when some of the levels of the dot are degenerate and again obtain good qualitative agreement with results obtained with alternative methods. As in the case of a single level, for temperatures larger than the Kondo temperature, the Kohn-Sham conductance fails to reproduce the typical Coulomb blockade peaks. This is attributed to {\em dynamical} exchange-correlation corrections to the conductance originating from time-dependent density functional theory.

8 pages, 4 figures, submitted to special issue of pss(b)

References in corpus (14)

• The discontinuous nature of the exchange-correlation functional -- critical for strongly correlated systems
• Time-dependent density-functional theory for open systems
• Dynamical corrections to the DFT-LDA electron conductance in nanoscale systems
• Piecewise Linearity of Approximate Density Functionals Revisited: Implications for Frontier Orbital Energies
• Strong correlation in Kohn-Sham density functional theory
• Universal Dynamical Steps in the Exact Time-Dependent Exchange-Correlation Potential
• Bound states in ab initio approaches to quantum transport: A time-dependent formulation
• Conserving Approximations in Time-Dependent Density Functional Theory
• Microscopic Current Dynamics in Nanoscale Junctions
• Time-dependent versus static quantum transport simulations beyond linear response
• Kohn-Sham density functional theory for quantum wires in arbitrary correlation regimes
• Dynamical correction to linear Kohn-Sham conductances from static density functional theory
• Local Control and v-Representability of Correlated Quantum Dynamics
• Time dependent transport phenomena

Cited by in corpus (12)

• Steady-State Density Functional Theory for Finite Bias Conductances
• Many-body spectral functions from steady state density functional theory
• Transport through correlated systems with density functional theory
• Nonequilibrium Anderson model made simple with density functional theory
• Density Functional Theory of the Seebeck coefficient in the Coulomb blockade regime
• Density functional description of Coulomb blockade: Adiabatic or dynamic exchange-correlation?
• Time-dependent i-DFT exchange-correlation potentials with memory: Applications to the out-of-equilibrium Anderson model
• Non-equilibrium spectral functions from multi-terminal steady-state density functional theory
• Exchange-correlation potentials for multi-orbital quantum dots subject to generic density-density interactions and Hund's rule coupling
• What can lattice DFT teach us about real-space DFT?
• Exchange-correlation functionals of i-DFT for asymmetrically coupled leads
• Level occupation switching with density functional theory