National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
J Phys Condens Matter. 2012 May 9;24(18):185504. doi: 10.1088/0953-8984/24/18/185504. Epub 2012 Apr 5.
A honeycomb lattice model exhibiting the quantum spin-Hall effect is proposed, where the low-energy properties of the electrons are mainly determined by the energy spectrum in the vicinity of the Γ point, for suitable parameters. The nontrivial topology of the energy bands is revealed by calculating the Chern numbers, Berry curvature distribution, and edge state spectrum. We further show that in the continuum limit, the model Hamiltonian is equivalent to the effective model for the surface states in thin films of three-dimensional topological insulators. As a consequence, this lattice model provides a useful tool for numerical simulation of the physical properties of the surface states.
提出了一个具有量子自旋霍尔效应的蜂窝格子模型，在合适的参数下，电子的低能性质主要由Γ点附近的能谱决定。通过计算陈数、Berry 曲率分布和边缘态谱，揭示了能带的非平凡拓扑结构。我们进一步表明，在连续极限下，模型哈密顿量等效于三维拓扑绝缘体薄膜中表面态的有效模型。因此，这个格子模型为表面态的物理性质的数值模拟提供了一个有用的工具。
