The electronic and topological properties of plumbene by first-principles calculations*

Combining tight-binding (TB) models with first-principles calculations, we investigate the electronic and topological properties of plumbene. “Constructive” coupling effects of topological states are found in the plumbene, causing the system being a normal insulator, opposite to topologically nontrivial states formed in the other group IVA monolayers. Based on this mechanism, several schemes are raised to produce a globally topological state in the plumbene. Interestingly, after the edge modification in the nanoribbon structure, the plumbene can own low-dissipation tunable edge states with good conduction performance despite the topologically trivial behavior.