First principles study on planar mechanism and heterostructures of ultraflat stanene

The successful preparation of ultraflat stanene on Cu (111) has broad application prospects in topological insulators. Here, we investigate the mechanism of stanene extending from buckled structure to ultraflat structure by using the first principle calculation. Different heterojunctions are constructed to clarify the influence of different structure heterojunctions on the topological properties of ultraflat stanene. The results show that the mechanism of planar structure is the joint action of pz orbital filtration and stress stretching. On this basis, we have established heterojunctions of ultraflat stanene with MoS2 and 4-SiC models and analyzed their topological properties. The results show that only the van der Waals heterojunction of ultraflat stanene on MoS2 is used as a substrate. The topological properties can be maintained. However, the heterojunction of ultraflat stanene on 4SiC with chemical bond changes the topological properties of ultraflat stanene. Therefore, the heterojunction of ultraflat stanene on MoS2 is a promising candidate for topological devices.

Automated summary

The successful preparation of ultraflat stanene on Cu (111) has potential applications in topological insulators. The mechanism behind the transition from a buckled structure to an ultraflat structure was investigated using first principle calculations. Different heterojunctions were constructed to analyze their impact on the topological properties of ultraflat stanene. The results indicate that only the van der Waals heterojunction of ultraflat stanene on MoS2 can maintain its topological properties, while chemical bond changes in the heterojunction with 4SiC alter the topological properties. The heterojunction of ultraflat stanene on MoS2 shows promise for topological devices.