Band engineering of Dirac materials in Sb(m)Bi(n) lateral heterostructures

Band engineering the electronic structures of Sb(m)Bi(n) lateral heterostructures (LHS) from antimonene and bismuthene is systematically investigated using first principles calculations. The spin–orbit coupling is found to be crucial in determining electronic structures of Sb(m)Bi(n) LHS. The results indicate that these lateral heterostructures have a type-II band alignment which can be easily tuned using their size and tensile strain. The band gap tends to zero when the lateral heterostructure size is larger than a critical value, which intrinsically corresponds to a semiconductor-to-semimetal transition. The band inversion near the Γ point occurs under suitable tensile strain, indicating that Sb(m)Bi(n) LHS are very promising to realize quantum spin Hall effects.