Time-dependent quantum transport through an interacting quantum dot beyond sequential tunneling: second-order quantum rate equations

Abstract

A general theoretical formulation for the effect of a strong on-site Coulomb interaction on the time-dependent electron transport through a quantum dot under the influence of arbitrary time-varying bias voltages and/or external fields is presented, based on slave bosons and the Keldysh nonequilibrium Green's function (GF) techniques. To avoid the difficulties of computing double-time GFs, we generalize the propagation scheme recently developed by Croy and Saalmann to combine the auxiliary-mode expansion with the celebrated Lacroix's decoupling approximation in dealing with the second-order correlated GFs and then establish a closed set of coupled equations of motion, called second-order quantum rate equations (SOQREs), for exact description of transient dynamics of electron correlated tunneling. We verify that the stationary solution of our SOQREs is able to correctly describe the Kondo effect on a qualitative level. Moreover, a comparison with other methods, such as the second-order von Neumann approach and Hubbard-I approximation, is performed. As illustrations, we investigate the transient current behaviors in response to a step voltage pulse and a harmonic driving voltage, and linear admittance as well, in the cotunneling regime.

16 pages, 9 figures

References in corpus (22)

• Driven quantum transport on the nanoscale
• An On-Demand Coherent Single Electron Source
• Real-time path integral approach to nonequilibrium many-body quantum system
• Single-parameter non-adiabatic quantized charge pumping
• Iterative real-time path integral approach to nonequilibrium quantum transport
• Tunneling through molecules and quantum dots: master-equation approaches
• Hierarchical Liouville-space approach for accurate and universal characterization of quantum impurity systems
• Time-dependent density-functional theory for open systems
• 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 time-dependent approach to electron pumping in open quantum systems
• Tunneling through nanosystems: Combining broadening with many-particle states
• The influence of ultra-fast laser pulses on electron transfer in molecular wires studied by a non-Markovian density matrix approach
• Transient dynamics of the Anderson impurity model out of equilibrium
• Anderson Model out of equilibrium: decoherence effects in transport through a quantum dot
• Transient regime in non-linear transport through many-level quantum dots
• Non adiabatic features of electron pumping through a quantum dot in the Kondo regime
• Hybrid NRG-DMRG approach to real-time dynamics of quantum impurity systems
• A partial fraction decomposition of the Fermi function
• Non-adiabatic transport in a quantum dot turnstile
• First-order coherent resonant tunneling through an interacting coupled-quantum-dot interferometer: generic quantum rate equations and current noise
• A diagrammatic description of the equations of motion, current, and noise within the second-order von Neumann approach