Abstract
By combining first-principles calculations with Wannier-based tight-binding modeling, we demonstrate that a heterostructure that was previously proposed as a prototypical semi-Dirac system becomes a Chern insulator (quantum anomalous Hall insulator) in the presence of spin-orbit coupling. We show that this occurs only when the semi-Dirac structure is of a special type that can be formed by the merging of three conventional Dirac points. Our results reveal how the nontrivial topology with a nonzero Chern number emerges naturally from this kind of semi-Dirac structure, establishing a general scenario that provides a different route to the formation of Chern-insulating states in practical materials systems.
- Received 3 July 2015
DOI:https://doi.org/10.1103/PhysRevB.92.161115
©2015 American Physical Society