[PO-J1] Poster Session 1

[P1-65] Multiscale Model for Interlayer Defects in Heterogeneous Bilayer Material

^○Shuyang Dai¹, David Joseph Srolovitz², Yang Xiang³ (1.Wuhan University, China, 2.University of Pennsylvania, United States of America, 3.Hong Kong University of Science and Technology, Hong Kong)

We present a multiscale model to describe the interlayer defects in bilayer materials. The model incorporates both the anisotropy elasticity of each layer and the first-principle calculation informed interaction between two layers, i.e., the 3-dimensional generalized stacking-fault energy. The force balance between these two contributions determines the structure. We apply this approach to determine the structure and energetics of twisted bilayer material. In twisted bilayer graphene, two distinct, modified Moiré structures are observed. We also study the buckling twisted heterogeneous bilayer material such as bilayer graphene/hexagonal boron nitride. We investigate the structure and corresponding dislocation network due to various misfits and twist angles between two layers. The relaxation of the Moiré structure reduces the symmetry and increases the period of the bilayer material. Our model agrees well with the atomistic results. An analytical description is developed based on the obtained structural features.