Phase structure of topological insulators by lattice strong-coupling expansion

Yasufumi Araki (1) , Taro Kimura (2, 3) , Akihiko Sekine (4) , Kentaro Nomura (4) , Takashi Z. Nakano (5)

1 University of Texas at Austin [Austin]
2 RIKEN - RIKEN - Institute of Physical and Chemical Research [Japon]
3 IPHT - Institut de Physique Théorique - UMR CNRS 3681
4 WPI-AIMR - WPI Advanced Institute for Materials Research
5 Kozo Keikaku Engineering Inc.

The effect of the strong electron correlation on the topological phase structure of 2-dimensional (2D) and 3D topological insulators is investigated, in terms of lattice gauge theory. The effective model for noninteracting system is constructed similarly to the lattice fermions with the Wilson term, corresponding to the spin-orbit coupling. Introducing the electron-electron interaction as the coupling to the gauge field, we analyze the behavior of emergent orders by the strong coupling expansion methods. We show that there appears a new phase with the in-plane antiferromagnetic order in the 2D topological insulator, which is similar to the so-called "Aoki phase" in lattice QCD with Wilson fermions. In the 3D case, on the other hand, there does not appear such a new phase, and the electron correlation results in the shift of the phase boundary between the topological phase and the normal phase.

Mots clés: Strongly Correlated Electrons (cond-mat.str-el); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); High Energy Physics - Lattice (hep-lat); High Energy Physics - Theory (hep-th)

Domaines: Physique des Hautes Energies - Réseau [hep-lat]; Physique des Hautes Energies - Théorie [hep-th]

Yasufumi Araki, Taro Kimura, Akihiko Sekine, Kentaro Nomura, Takashi Z. Nakano. Phase structure of topological insulators by lattice strong-coupling expansion. 31st International Symposium on Lattice Field Theory - LATTICE 2013, Jul 2013, Mainz, Germany. pp.50. ⟨cel-01335764⟩