### Abstract

The phase structure of two-dimensional topological insulators under a sufficiently strong electron-electron interaction is investigated. The effective theory is constructed by extending the idea of the Kane-Melé model on the graphenelike honeycomb lattice, in terms of U(1) lattice gauge theory (quantum electrodynamics). We analyze the phase structure by the techniques of strong-coupling expansion of lattice gauge theory. As a result, we find that the topological phase structure of the system is modified by the electron-electron interaction. There evolves a new phase with the antiferromagnetism not parallel to the direction pointed by the spin-orbit coupling, in-between the conventional and the topological insulator phases. We also discuss the physical implication of the new phase structure found here, in analogy to the parity-broken phase in lattice quantum chromodynamics, known as the "Aoki phase."

Original language | English |
---|---|

Article number | 205440 |

Journal | Physical Review B - Condensed Matter and Materials Physics |

Volume | 87 |

Issue number | 20 |

DOIs | |

Publication status | Published - 2013 May 29 |

Externally published | Yes |

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### ASJC Scopus subject areas

- Condensed Matter Physics
- Electronic, Optical and Magnetic Materials

### Cite this

*Physical Review B - Condensed Matter and Materials Physics*,

*87*(20), [205440]. https://doi.org/10.1103/PhysRevB.87.205440

**Phase structure of two-dimensional topological insulators by lattice strong-coupling expansion.** / Araki, Yasufumi; Kimura, Taro.

Research output: Contribution to journal › Article

*Physical Review B - Condensed Matter and Materials Physics*, vol. 87, no. 20, 205440. https://doi.org/10.1103/PhysRevB.87.205440

}

TY - JOUR

T1 - Phase structure of two-dimensional topological insulators by lattice strong-coupling expansion

AU - Araki, Yasufumi

AU - Kimura, Taro

PY - 2013/5/29

Y1 - 2013/5/29

N2 - The phase structure of two-dimensional topological insulators under a sufficiently strong electron-electron interaction is investigated. The effective theory is constructed by extending the idea of the Kane-Melé model on the graphenelike honeycomb lattice, in terms of U(1) lattice gauge theory (quantum electrodynamics). We analyze the phase structure by the techniques of strong-coupling expansion of lattice gauge theory. As a result, we find that the topological phase structure of the system is modified by the electron-electron interaction. There evolves a new phase with the antiferromagnetism not parallel to the direction pointed by the spin-orbit coupling, in-between the conventional and the topological insulator phases. We also discuss the physical implication of the new phase structure found here, in analogy to the parity-broken phase in lattice quantum chromodynamics, known as the "Aoki phase."

AB - The phase structure of two-dimensional topological insulators under a sufficiently strong electron-electron interaction is investigated. The effective theory is constructed by extending the idea of the Kane-Melé model on the graphenelike honeycomb lattice, in terms of U(1) lattice gauge theory (quantum electrodynamics). We analyze the phase structure by the techniques of strong-coupling expansion of lattice gauge theory. As a result, we find that the topological phase structure of the system is modified by the electron-electron interaction. There evolves a new phase with the antiferromagnetism not parallel to the direction pointed by the spin-orbit coupling, in-between the conventional and the topological insulator phases. We also discuss the physical implication of the new phase structure found here, in analogy to the parity-broken phase in lattice quantum chromodynamics, known as the "Aoki phase."

UR - http://www.scopus.com/inward/record.url?scp=84878561123&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84878561123&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.87.205440

DO - 10.1103/PhysRevB.87.205440

M3 - Article

AN - SCOPUS:84878561123

VL - 87

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 20

M1 - 205440

ER -