2134/10011236.v1
Petri Hirvonen
Petri
Hirvonen
Vili Heinonen
Vili
Heinonen
Haikuan Dong
Haikuan
Dong
Zheyong Fan
Zheyong
Fan
Ken R Elder
Ken R
Elder
Tapio Ala-Nissila
Tapio
Ala-Nissila
Phase-field crystal model for heterostructures
Loughborough University
2019
Uncategorised value
2019-10-22 13:45:12
Journal contribution
https://repository.lboro.ac.uk/articles/journal_contribution/Phase-field_crystal_model_for_heterostructures/10011236
Atomically thin two-dimensional heterostructures are a promising, novel class of materials with groundbreaking properties. The possibility of choosing many constituent components and their proportions allows
optimization of these materials to specific requirements. The wide adaptability comes with a cost of large
parameter space making it hard to experimentally test all the possibilities. Instead, efficient computational
modeling is needed. However, large range of relevant time and length scales related to physics of polycrystalline
materials poses a challenge for computational studies. To this end, we present an efficient and flexible phase-field
crystal model to describe the atomic configurations of multiple atomic species and phases coexisting in the same
physical domain. We extensively benchmark the model for two-dimensional binary systems in terms of their
elastic properties and phase boundary configurations and their energetics. As a concrete example, we demonstrate
modeling lateral heterostructures of graphene and hexagonal boron nitride. We consider both idealized bicrystals
and large-scale systems with random phase distributions. We find consistent relative elastic moduli and lattice
constants, as well as realistic continuous interfaces and faceted crystal shapes. Zigzag-oriented interfaces are
observed to display the lowest formation energy.