Spin-orbit gap of graphene: First-principles calculations
Spin-orbit gap of graphene: First-principles calculations
复制标题
石墨烯的自旋轨道间隙：第一性原理计算
DOI：
10.1103/physrevb.75.041401
复制
发表时间：
2007-01-01
影响因子：
3.7
通讯作者：
Fang, Zhong
中科院分区：
文献类型：
--
作者：
Yao, Yugui;Ye, Fei;Fang, Zhong
尽管石墨烯是由碳原子的二维蜂窝晶格组成的低能系统，但其准粒子激发完全由（2+1）维相对论狄拉克方程描述。在本文中，我们表明，虽然石墨烯中的自旋轨道相互作用是4 meV的数量级，它打开了一个10（-3）meV的数量级的狄拉克点的差距。我们提出了一个第一性原理计算的自旋轨道间隙，并解释了一个简单的紧束缚模型的行为。我们的结果还表明，最近预测的量子自旋霍尔效应在石墨烯只能发生在不切实际的低温。
Even though graphene is a low-energy system consisting of a two-dimensional honeycomb lattice of carbon atoms, its quasiparticle excitations are fully described by the (2+1)-dimensional relativistic Dirac equation. In this paper we show that, while the spin-orbit interaction in graphene is of the order of 4 meV, it opens up a gap of the order of 10(-3) meV at the Dirac points. We present a first-principles calculation of the spin-orbit gap, and explain the behavior in terms of a simple tight-binding model. Our result also shows that the recently predicted quantum spin Hall effect in graphene can occur only at unrealistically low temperature.