Abstract
We study the tight-binding model of the square-hexagon lattice, which supports two kinds of nearest-neighbor hoppings and spin-orbit couplings. Based on the parity criterion and Fukui-Hatsugai method, the topological properties are investigated. In the presence of spin-orbit coupling, topological phase transition between topological semimetal and normal band insulator can be realized. The phase diagrams as a function of the spin-orbit couplings, and , are presented. Also, the effects of the Rashba spin-orbit coupling and staggered potential are discussed. We find that the Rashba spin-orbit coupling can drive the square-hexagon lattice into topological nontrivial phase at 1/5 and 2/5 filling fraction. The helical edge states are given numerically to confirm the topological property of square-hexagon lattice. Our results enlarge the number of two-dimensional lattices which have only a simple cubic symmetry and can support topological nontrivial phase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
