School of Mechanical Engineering Prof. Ellad Tadmor

School of Mechanical Engineering Seminar
Wednesday, June 28, 2017 at 14:00
Wolfson Building of Mechanical Engineering, Room 206

Multiscale Simulation of 2D Heterostructures: Incommensurate to Commensurate Transformations in Twisted Graphene Bilayers

Prof. Ellad B. Tadmor

Department of Aerospace Engineering and Mechanics

University of Minnesota

The synthesis of graphene, a one-atom thick 2D graphitic sheet, was a revolution in materials physics. Since then a host of other 2D materials have been discovered that can be stacked to create layered heterostructures with remarkable properties. Due to the weak van der Waals interaction between layers, the resulting structures can be incommensurate and therefore challenging to model. We describe recent work on developing a hybrid continuum-atomistic computational framework for simulating the mechanical response of 2D heterostructures. In agreement with electron diffraction experiments, simulations of twisted bilayer graphene show a transformation from an initially incommensurate structure to commensurate structures separated by localized solitons. This behavior is explained using a simple mechanical model.

‏