Misfit strain-induced buckling for transition-metal dichalcogenide lateral heterostructures: a molecular dynamics study

Molecular dynamics simulations are performed to investigate the misfit strain-induced buckling of the transition-metal dichalcogenide (TMD) lateral heterostructures, denoted by the seamless epitaxial growth of different TMDs along the in-plane direction. The Stillinger-Weber potential is utilized to describe both the interaction for each TMD and the coupling between different TMDs, i.e., MX2 (with M=Mo, W and X=S, Se, Te). It is found that the misfit strain can induce strong buckling of the free-standing TMD lateral heterostructures of large area, resulting from the TMDs' atomic-thick nature. The buckling phenomenon occurs in a variety of TMD lateral heterostructures of different compositions and in various patterns. Our findings raise a fundamental mechanical challenge for the structural stability of the free-standing TMD lateral heterostructures.