Integer quantum Hall effect in a triangular-lattice: Disorder effect and scaling behavior of the insulator-plateau transition. (January 2017)

• Record Type: Journal Article
• Authors: Yu, H.L.; Jiang, C.; Zhai, Z.Y.
• Is Part Of: Solid state communications. Volume 249(2017)
• Page Start: 44
• Page End: 47
• Publication Date: 2017-01
• Subjects: Integer quantum Hall effect -- Chern number -- Quantum phase transition; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2016.10.015
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: We investigate numerically the integer quantum Hall effect in a three-band triangular-lattice model. The three bands own the Chern number C=2, −1, −1, respectively. The lowest topological flat band carrying Chern number C=2, which leads to the Hall plateau σ H = 2 ( e 2 / h ) . This Hall plateau is sensitive to the disorder scattering and is rapidly destroyed by the weak disorder. Further increasing the strength of disorder, the gap of density of states always disappears before the vanishing of the corresponding Hall plateau. The scaling behavior of quantum phase transition between an insulator and a quantum Hall plateau is studied. We find that the insulator-plateau transition becomes sharper with increasing the size of system. Due to the different of edge states, the critical energy E c 1 gradually shifts to the center of Hall plateau while E c 2 is unaffected with increasing the disorder strength. Highlights: Three energy bands are created in a triangular-lattice model. The Hall plateau with C=2 is sensitive to the disorder scattering. The insulator-plateau transition becomes sharper with increasing the size of system. The disorder dependence of the critical energy is investigated.