Theory of I-V characteristics for two-dimensional charge-ordered electron systems at quarter filling

Yasuhiro Tanaka, Kenji Yonemitsu

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The current-voltage characteristics and charge distribution of charge-ordered electron systems at quarter-filling under an applied bias voltage (V) are investigated theoretically by using nonequilibrium Green's functions. We consider an extended Hubbard model with long-range Coulomb interactions on a square lattice, which describes a checkerboard-type charge order in the absence of the bias V. The effects of metallic electrodes are incorporated into the self-energy. The electron density and a scalar potential that satisfies the Poisson equation with a suitable boundary condition are calculated self-consistently within the Hartree approximation. A first-order transition is observed from the charge-ordered insulating state to a conductive state with increasing V. In the former state, the charge distribution is almost unchanged by V, whereas the charge order disappears so that the charge distribution is basically uniform in the latter state.

Original languageEnglish
JournalPhysica B: Condensed Matter
Volume405
Issue number11 SUPPL.
DOIs
Publication statusPublished - 2010 Jun 1
Externally publishedYes

Fingerprint

Charge distribution
charge distribution
Electrons
Hartree approximation
Hubbard model
electrons
Poisson equation
electric potential
Current voltage characteristics
Bias voltage
Coulomb interactions
Green's function
Carrier concentration
Green's functions
Boundary conditions
boundary conditions
scalars
Electrodes
electrodes
interactions

Keywords

  • Charge order
  • I-V characteristics
  • Nonequilibrium Green's function

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this

Theory of I-V characteristics for two-dimensional charge-ordered electron systems at quarter filling. / Tanaka, Yasuhiro; Yonemitsu, Kenji.

In: Physica B: Condensed Matter, Vol. 405, No. 11 SUPPL., 01.06.2010.

Research output: Contribution to journalArticle

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