期刊
PHYSICAL REVIEW B
卷 90, 期 7, 页码 -出版社
AMER PHYSICAL SOC
DOI: 10.1103/PhysRevB.90.075114
关键词
-
资金
- NSF [DMR-1410375]
- AFOSR [FA9550-11-1-0067]
- Inamori Fellowship
- Princeton Center for Theoretical Science
- National Natural Science Foundation of China [11328403]
- Division Of Materials Research [1410375] Funding Source: National Science Foundation
We construct a minimal four-band model for the two-dimensional (2D) topological insulators and quantum anomalous Hall insulators based on the p(x) -and p(y) -orbital bands in the honeycomb lattice. The multiorbital structure allows the atomic spin-orbit coupling which lifts the degeneracy between two sets of on-site Kramers doublets j(z) = +/- 3/2 and j(z) = +/- 1/2. Because of the orbital angular momentum structure of Bloch-wave states at Gamma and K (K') points, topological gaps are equal to the atomic spin-orbit coupling strengths, which are much larger than those based on the mechanism of the s-p band inversion. In the weak and intermediate regime of spin-orbit coupling strength, topological gaps are the global gap. The energy spectra and eigen wave functions are solved analytically based on Clifford algebra. The competition among spin-orbit coupling lambda, sublattice asymmetrym, and the Neel exchange field n results in band crossings at Gamma and K (K') points, which leads to various topological band structure transitions. The quantum anomalous Hall state is reached under the condition that three gap parameters., m, and n satisfy the triangle inequality. Flat bands also naturally arise which allow a local construction of eigenstates. The above mechanism is related to several classes of solid state semiconducting materials.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据