White Rose University Consortium logo
University of Leeds logo University of Sheffield logo York University logo

Generalization and applicability of the Landauer formula for nonequilibrium current in the presence of interactions

Ness, H., Dash, L.K. and Godby, R. (2010) Generalization and applicability of the Landauer formula for nonequilibrium current in the presence of interactions. Physical Review B (PRB). 085426. -. ISSN 1098-0121

Full text available as:
[img] Other (Fwd_Re_Generalization_and_applicability_of_the_Landauer_formula_for_nonequilibrium_current_in_the_presence_of_interactions.txt)
Fwd_Re_Generalization_and_applicability_of_the_Landauer_formula_for_nonequilibrium_current_in_the_presence_of_interactions.txt

Download (3767b)

Abstract

Using nonequilibrium Green's functions (NEGFs), we calculate the current through an interacting region connected to noninteracting leads. The problem is reformulated in such a way that a Landauer-like term appears in the current as well as extra terms corresponding to nonequilibrium many-body effects. The interaction in the central region renormalizes not only the Green's functions but also the coupling at the contacts between the central region and the leads, allowing the total current to be further expressed as a generalized Landauer-like current formula. The general expression for the dynamical functional that renormalizes the contacts is provided. We analyze in detail under what circumstances Landauer-like approaches to the current, i.e., without contact renormalization, are valid for interacting electron-electron and/or electron-phonon systems. Numerical NEGF calculations are then performed for a model electron-phonon coupled system in order to validate our analytical approach. We show that the conductance for the off-resonant transport regime is adequately described by Landauer-like approach in the small-bias limit while for the resonant regime, the Landauer-like approach results depart from the exact results even at small finite bias. The validity of applying a Landauer-like approach to inelastic electron-tunneling spectroscopy is also studied in detail.

Item Type: Article
Copyright, Publisher and Additional Information: © 2010 American Physical Society. This is an author produced version of a paper published in Physical Review B. Uploaded in accordance with the publisher's self archiving policy.
Keywords: CURRENT-VOLTAGE CHARACTERISTICS, SCANNING-TUNNELING-MICROSCOPY, KADANOFF-BAYM EQUATIONS, GREENS-FUNCTIONS, TRANSPORT-PROPERTIES, MOLECULAR JUNCTIONS, QUANTUM TRANSPORT, ANDERSON IMPURITY, CONDUCTANCE, SCATTERING, Condensed Matter Physics, Electronic, Optical and Magnetic Materials
Institution: The University of York
Academic Units: The University of York > Physics (York)
Depositing User: Repository Administrator York
Date Deposited: 12 Oct 2010 14:34
Last Modified: 20 Aug 2014 11:19
Published Version: http://dx.doi.org/10.1103/PhysRevB.82.085426
Status: Published
Refereed: Yes
Related URLs:
URI: http://eprints.whiterose.ac.uk/id/eprint/15186

Actions (login required)

View Item View Item