Perturbation Study of the Conductance through an Interacting Region Connected to Multi-Mode Leads

Abstract

We study the effects of electron correlation on transport through an interacting region connected to multi-mode leads based on the perturbation expansion with respect to the inter-electron interaction. At zero temperature the conductance defined in the Kubo formalism can be written in terms of a single-particle Green's function at the Fermi energy, and it can be mapped onto a transmission coefficient of the free quasiparticles described by an effective Hamiltonian. We apply this formulation to a two-dimensional Hubbard model of finite size connected to two noninteracting leads. We calculate the conductance in the electron-hole symmetric case using the order $U^2$ self-energy. The conductance shows several maximums in the $U$ dependence in some parameter regions of $t_y/t_x$, where $t_x$ ($t_y$) is the hopping matrix element in the $x$- ($y$-) directions. This is caused by the resonance occurring in some of the subbands, and is related with the $U$ dependence of the eigenvalues of the effective Hamiltonian.

17 pages, 12 figures, to be published in J.Phys.Soc.Jpn. 71(2002)No.1

References in corpus (3)

• Fermi liquid theory for the Anderson model out of equilibrium
• Transmission Probability for Interacting Electrons Connected to Reservoirs
• Quasi-particle description for the transport through a small interacting system

Cited by in corpus (7)

• Numerical renormalization group approach to a quartet quantum-dot array connected to reservoirs:gate-voltage dependence of the conductance
• Correlated electron transport through double quantum dots coupled to normal and superconducting leads
• Crossover between two different Kondo couplings in side-coupled double quantum dots
• Determination of the phase shifts for interacting electrons connected to reservoirs
• NRG approach to the transport through a finite Hubbard chain connected to reservoirs
• Effects of disorder on conductance through small interacting systems
• Effects of Electron Correlation on the Transport through a Quantum Dot Superlattice