Effects of strain on electronic properties of graphene
Effects of strain on electronic properties of graphene
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DOI：
10.1103/physrevb.81.081407
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发表时间：
2010-02-01
影响因子：
3.7
通讯作者：
Son, Young-Woo
中科院分区：
文献类型：
--
作者：
Choi, Seon-Myeong;Jhi, Seung-Hoon;Son, Young-Woo
我们提出了第一性原理计算的单轴和各向同性应变下的石墨烯的电子性质，分别。的半金属性质示出坚持到一个非常大的单轴应变30%，除了一个非常窄的应变范围，其中一个微小的能隙打开。当单轴应变沿某一方向沿着增加时，平行于该方向的费米速度迅速减小并最终消失，而垂直于该方向的费米速度则增加了25%。因此，当无质量和有质量的电子与大的电子共存时，具有小的单轴应变的低能性质可以由广义Weyl方程描述。的功函数也被预测为单轴和各向同性应变增加大幅增加。因此，石墨烯中的均匀应变可以被视为有效电子标量势。
We present first-principles calculations of electronic properties of graphene under uniaxial and isotropic strains, respectively. The semimetallic nature is shown to persist up to a very large uniaxial strain of 30% except a very narrow strain range where a tiny energy gap opens. As the uniaxial strain increases along a certain direction, the Fermi velocity parallel to it decreases quickly and vanishes eventually, whereas the Fermi velocity perpendicular to it increases by as much as 25%. Thus, the low energy properties with small uniaxial strains can be described by the generalized Weyl's equation while massless and massive electrons coexist with large ones. The work function is also predicted to increase substantially as both the uniaxial and isotropic strain increases. Hence, the homogeneous strain in graphene can be regarded as the effective electronic scalar potential.