摘要
Negative Poisson’s ratio(NPR)materials are functional and mechanical metamaterials that shrink(expand)longitudinally after being compressed(stretched)laterally.By using first-principles calculations,we found that Poisson’s ratio can be tuned from near zero to negative by different stacking modes in van der Waals(vdW)graphene/hexagonal boron nitride(G/h-BN)superlattice.We attribute the NPR effect to the interaction of pz orbitals between the interfacial layers.Furthermore,a parameter calculated by analyzing the electronic band structure,namely,distance-dependent hopping integral,is used to describe the intensity of this interaction.We believe that this mechanism is not only applicable to G/h-BN superlattice but can also explain and predict the NPR effect in other vdW layered superlattices.Therefore,the NPR phenomenon,which was relatively rare in 3D and 2D materials,can be realized in the vdW superlattices by different stacking orders.The combinations of tunable NPRs with the excellent electrical/optical properties of 2D vdW superlattices will pave a novel avenue to a wide range of multifunctional applications.
出处
《Research》
SCIE
EI
CAS
CSCD
2021年第1期50-60,共11页
研究（英文）
基金
supported by the Center for Computational Science and Engineering of Southern University of Science and Technology,NSFC(National Natural Science Foundation of China)grant number 51972160
the Science and Technology Research Items of Shenzhen grant numbers JCYJ20170412153325679,JCYJ20180504165650580,JCYJ20190809142603695,and JCYJ20170817110302672
High-level Special Funding(Nos.G02206303 and G02206403).
