Detail:
Abstract: When atomically thin two-dimensional materials are layered, they often form incommensurate noncrystalline structures that exhibit long-period moire patterns when examined by scanning probes. In this talk I present a methodology that uses information obtained from ab initio calculations performed on short-period crystalline structures to derive effective Hamiltonians that are able to efficiently describe the influence of the moire pattern superlattices on electronic properties. We applied our approach to obtain the Hamiltonian of graphene on hexagonal boron nitride (G/BN) that can be used to calculate electronic properties of interest for arbitrary twist angles and lattice constants. We show that our multiscale approach can be used to obtain electronic structure models that have predictive accuracy, and that moire strains can play an important role in reconfiguring the mechanical and electronic properties of G/BN such as its band gap. The bridge between the continuum and the lattice Hamiltonian established by our theory can be used in realistic simulations of G/BN subject to disorder or perpendicular magnetic fields.
Biosketch： Dr. Jeil Jung obtained his PhD degree at National Distance Education University, Madrid, Spain in 2005. Thereafter, he worked as a Fulbright research fellow in Prof. Allan MacDonald’s group at University of Texas at Austin from 2006-2013 and a Senior Research Fellow at National University of Singapore from 2013-2015. Since 2015 he joined University of Seoul as an Associate Professor.
