六角氮化硼(h-BN)对单层硒化铟(InSe)的调制效应及这一新结构的电子性质

Modulation effect of monolayer h-BN on InSe and the electronic properties of this new structure

采用基于密度泛函理论的第一性原理计算和分析了三种InSe/h-BN异质结的结构和电子性质.研究发现InSe/h-BN异质结具有间接带隙特点,并且价带顶和导带底的贡献均来自于InSe,差分电荷密度表明体系中没有明显的电荷交换.通过体系能带结构,我们发现h-BN层对单层InSe有着明显的调控效应.对比纯粹应变调控下单层的InSe的能带结构,发现h-BN对InSe能带结构的调控效应实际上是由InSe和h-BN之间的相互作用而诱导的晶格应变引起的.我们的研究结果表明,单层InSe沉积或生长在不同h-BN片上可以获得不同的晶格应变,实现对单层InSe能带结构的有效调控.

First-principles based on density functional theory(DFT)are used to calculate and analyze the structural and electronic properties of three InSe/h-BN heterostructures.We find that the InSe/h-BN heterostructures show indirect bandgap features with both of CBM and VBM localized on the monolayer InSe.Difference charge density indicates that there is no obvious charge exchange between layers.By calculating the energy band structure of the system,we find that the h-BN layer has a significant regulatory effect on the monolayer InSe.Comparing the energy band structure of monolayer InSe under pure strain control,it is found that the regulation effect of h-BN on InSe band structure is caused by the lattice strain induced by the interaction between InSe and h-BN.Our results show that a monolayer of InSe can be deposited or grown on different h-BN sheets to obtain different lattice strains,which can effectively control the single-layer InSe energy band.