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 |
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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 journal › Article
}
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 -