Exact Green's function for a multi-orbital Anderson impurity at high bias voltages
arXiv:1412.6718 · doi:10.1103/PhysRevB.91.115429
Abstract
We study the nonequilibrium Keldysh Green's function for an N-orbital Anderson model at high bias voltages, extending a previous work, which for the case only with the spin degrees of freedom N=2, to arbitrary N. Our approach uses an effective non-Hermitian Hamiltonian that is defined with respect to a Liouville-Fock space in the context of a thermal field theory. The result correctly captures the relaxation processes at high energies, and is asymptotically exact not only in the high-bias limit but also in the high-temperature limit at thermal equilibrium. We also present an explicit continued-fraction representation of the Green's function. It clearly shows that the imaginary part is recursively determined by the decay rate of intermediate states with at most N-1 particle-hole-pair excitations. These high-bias properties follow from the conservations of a generalized charge and current in the Liouville-Fock space. We also examine temperature dependence of the spectral function in equilibrium, comparing the exact results with both the finite-T and infinite-T results of the non-crossing approximation (NCA).
arXiv comment16 pages, 6 figures, typos have been corrected and DOI has been provided
References in corpus (32)
- Nonequilibrium fluctuations, fluctuation theorems, and counting statistics in quantum systems
- The Anderson Model out of Equilibrium: Non-Crossing-Approximation Approach to Transport through a Quantum Dot
- Diagrammatic Monte Carlo simulation of non-equilibrium systems
- On steady-state currents through nano-devices: a scattering-states numerical renormalization group approach to open quantum systems
- Universality of the Kondo Effect in a Quantum Dot out of Equilibrium
- Universal Scaling in Non-equilibrium Transport Through a Single-Channel Kondo Dot
- Towards full counting statistics for the Anderson impurity model
- Fractional Shot Noise in the Kondo Regime
- Fermi liquid theory for the Anderson model out of equilibrium
- Noisy Kondo impurities
- Two-electron bunching in transport through a QD induced by Kondo correlations
- Evolution of the Kondo Effect in a Quantum Dot Probed by the Shot Noise
- Theory of non-equilibrium transport in the SU(N) Kondo regime
- Universal Scaling of Nonequilibrium Transport in the Kondo Regime of Single Molecule Devices
- Fermionic superoperators for zero-temperature non-linear transport: real-time perturbation theory and renormalization group for Anderson quantum dots
- Non-equilibrium Differential Conductance through a Quantum Dot in a Magnetic Field
- Quantum Noise Measurement of a Carbon Nanotube Quantum Dot in the Kondo Regime
- Shot noise near the unitary limit of a Kondo quantum dot
- Time-dependent DMRG Study on Quantum Dot under a Finite Bias Voltage
- Time-dependent quantum transport: causal superfermions, exact fermion-parity protected decay mode, and Pauli exclusion principle for mixed quantum states
- Anderson impurity model in nonequilibrium: analytical results versus quantum Monte Carlo data
- Conserving Diagrammatic Approximations for Quantum Impurity Models: NCA and CTMA
- The Kondo crossover in shot noise of a single quantum dot with orbital degeneracy
- Full counting statistics for SU(N) impurity Anderson model
- Extension of the Non-Crossing Approximation for the Anderson Model with Finite Coulomb Repulsion
- Out-of-equilibrium Anderson model at high and low bias voltages
- Second-order post-Hartree-Fock perturbation theory for the electron current
- Imaginary-time quantum many-body theory out of equilibrium I: Formal equivalence to Keldysh real-time theory and calculation of static properties
- Full counting statistics for orbital-degenerate impurity Anderson model with Hund's rule exchange coupling
- 1/(N-1) expansion based on a perturbation theory in U for the Anderson model with N-fold degeneracy
- 1/(N-1) expansion for a finite U Anderson model away from half-filling
- Exact interacting Green's function for the Anderson impurity at high bias voltages