Comparison between scattering-states numerical renormalization group and the Kadanoff-Baym-Keldysh approach to quantum transport: Crossover from weak to strong correlations

Abstract

The quantum transport through nanoscale junctions is governed by the charging energy $U$ of the device. We employ the recently developed scattering-states numerical renormalization group approach to open quantum systems to study nonequilibrium Green functions and current-voltage characteristics of such junctions for small and intermediate values of $U$. The reliability of the approach is established by the excellent agreement with diagrammatic Kadanoff-Baym-Keldysh results at small values of the $U$. We demonstrate the limits of the diagrammatic approaches at intermediate Coulomb repulsion. These approaches predict two different low-energy scale for magnetic and charge fluctuations in zero bias while the numerical renormalization group approach correctly yields only one single, universal scale. At large voltages and intermediate values of the Coulomb repulsion the self-consistent second Born as well as the GW approximation reproduce the SNRG spectral functions quite well for a symmetric junctions, while for the asymmetric model the voltage-dependent redistribution of spectral weight differs significantly. The second-order perturbation theory does not capture the correct single-particle dynamics at large bias and violates current conservation for asymmetric junctions.

To be published in Phys. Rev. B 81, Issue 16

References in corpus (24)

• Single-shot read-out of an individual electron spin in a quantum dot
• The numerical renormalization group method for quantum impurity systems
• Real-time dynamics in Quantum Impurity Systems: A Time-dependent Numerical Renormalization Group Approach
• Real-time path integral approach to nonequilibrium many-body quantum system
• Diagrammatic Monte Carlo simulation of non-equilibrium systems
• A Numerical Renormalization Group approach to Green's Functions for Quantum Impurity Models
• Spin Precession and Real Time Dynamics in the Kondo Model: A Time-Dependent Numerical Renormalization-Group Study
• Conserving GW scheme for nonequilibrium quantum transport in molecular contacts
• On steady-state currents through nano-devices: a scattering-states numerical renormalization group approach to open quantum systems
• Iterative real-time path integral approach to nonequilibrium quantum transport
• Real-time simulations of nonequilibrium transport in the single-impurity Anderson model
• Twofold advance in the theoretical understanding of far-from-equilibrium properties of interacting nanostructures
• A perturbative nonequilibrium renormalization group method for dissipative quantum mechanics: Real-time RG in frequency space (RTRG-FS)
• Universal Scaling in Non-equilibrium Transport Through a Single-Channel Kondo Dot
• Weak-coupling quantum Monte Carlo calculations on the Keldysh contour: theory and application to the current-voltage characteristics of the Anderson model
• Impurity and correlation effects on transport in one-dimensional quantum wires
• Imaginary-time formulation of steady-state nonequilibrium: application to strongly correlated transport
• Relaxation vs decoherence: Spin and current dynamics in the anisotropic Kondo model at finite bias and magnetic field
• Electronic correlation in nanoscale junctions: Comparison of the GW approximation to a numerically exact solution of the single-impurity Anderson model
• Nonequilibrium magnetotransport through a quantum dot: An interpolative perturbative approach
• Time-dependent DMRG Study on Quantum Dot under a Finite Bias Voltage
• A Numerical Renormalization Group approach to Non-Equilibrium Green's Functions for Quantum Impurity Models
• The Coulomb Blockade in Quantum Boxes
• Magnetic-Field-Induced Crossover to a Nonuniversal Regime in a Kondo Dot

Cited by in corpus (35)

• Comparative study of theoretical methods for nonequilibrium quantum transport
• Transport through an Anderson impurity: Current ringing, non-linear magnetization and a direct comparison of continuous-time quantum Monte Carlo and hierarchical quantum master equations
• Comparative study of many-body perturbation theory and time-dependent density functional theory in the out-of-equilibrium Anderson model
• Green's function methods for single molecule junctions
• Influence of vibrational modes on the quantum transport through a nano-device
• Nonequilibrium perturbation theory in Liouville-Fock space for inelastic electron transport
• Spatial and temporal propagation of Kondo correlations
• Markovian Treatment of non-Markovian Dynamics of Open Fermionic Systems
• Many-body Green's function theory for electron-phonon interactions: the Kadanoff-Baym approach to spectral properties of the Holstein dimer
• Coherent control of correlated nanodevices: A hybrid time-dependent numerical renormalization-group approach to periodic switching
• Auxiliary master equation for nonequilibrium dual-fermion approach
• Nonequilibrium Zeeman-splitting in quantum transport through nanoscale junctions
• Effective Equilibrium Theory of Nonequilibrium Quantum Transport
• Effective Equilibrium Description of Nonequilibrium Quantum Transport I: Fundamentals and Methodology
• Imaginary-time formulation of steady-state nonequilibrium in quantum dot models
• Adiabatic Preparation of a Correlated Symmetry-Broken Initial State with the Generalized Kadanoff--Baym Ansatz
• Second-order post-Hartree-Fock perturbation theory for the electron current
• Build-up of the Kondo effect from real-time 2PI effective action for the Anderson impurity model
• Time-Dependent and Steady-State Gutzwiller approach for nonequilibrium transport in nanostructures
• Consistent bosonization-debosonization II: The two-lead Kondo problem and the fate of its non-equilibrium Toulouse point
• Kinks in the electronic dispersion of the Hubbard model away from half filling
• Hamiltonian approach to the charge transfer statistics of Kondo quantum dots contacted by a normal metal and a superconductor
• Transient dynamics and steady state behavior of the Anderson-Holstein model with a superconducting lead
• Transport properties of fully screened Kondo models
• Nonequilibrium Kondo effect by equilibrium numerical renormalization group method: The hybrid Anderson model subject to a finite spin bias
• Hierarchical equations of motion approach to transport through an Anderson impurity coupled to interacting Luttinger liquid leads
• Non-equilibrium quantum transport through a dissipative resonant level
• 1/(N-1) expansion for a finite U Anderson model away from half-filling
• Double Occupancy and Magnetic Susceptibility of the Anderson Impurity Model out of Equilibrium
• Real-time effective-action approach to the Anderson quantum dot
• Spectral Density Modulation and Universal Markovian Closure of Fermionic Environments
• Equilibrium and real-time properties of the spin correlation function in the two-impurity Kondo model
• Nonequilibrium dual-boson approach
• Restoring the continuum limit in the time-dependent numerical renormalization group approach
• Quantum transport through a molecular level: a scattering states numerical renormalisation group study