### 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 language | English |
---|---|

Journal | Physica B: Condensed Matter |

Volume | 405 |

Issue number | 11 SUPPL. |

DOIs | |

Publication status | Published - 2010 Jun 1 |

Externally published | Yes |

### Fingerprint

### 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

*Physica B: Condensed Matter*,

*405*(11 SUPPL.). https://doi.org/10.1016/j.physb.2009.12.065

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

Research output: Contribution to journal › Article

*Physica B: Condensed Matter*, vol. 405, no. 11 SUPPL.. https://doi.org/10.1016/j.physb.2009.12.065

}

TY - JOUR

T1 - Theory of I-V characteristics for two-dimensional charge-ordered electron systems at quarter filling

AU - Tanaka, Yasuhiro

AU - Yonemitsu, Kenji

PY - 2010/6/1

Y1 - 2010/6/1

N2 - 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.

AB - 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.

KW - Charge order

KW - I-V characteristics

KW - Nonequilibrium Green's function

UR - http://www.scopus.com/inward/record.url?scp=79961010954&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79961010954&partnerID=8YFLogxK

U2 - 10.1016/j.physb.2009.12.065

DO - 10.1016/j.physb.2009.12.065

M3 - Article

AN - SCOPUS:79961010954

VL - 405

JO - Physica B: Condensed Matter

JF - Physica B: Condensed Matter

SN - 0921-4526

IS - 11 SUPPL.

ER -