论文标题
Su-Schrieffer-Heeger模型中的分数费用
Fractional Charges in the Su-Schrieffer-Heeger Model
论文作者
论文摘要
Su-Schrieffer-Heeger（SSH）模型已被广泛用于研究1D系统的拓扑特性。据称，在非平凡阶段的边界处有分数电荷，而在琐碎阶段则没有电荷。但是，这个结论与现代极化理论（MTP）直接矛盾。我们通过表明SSH模型的极化仅取决于正电荷的分布，并且与以前的工作中定义的Zak相无关，我们可以解决这一悖论。因此，仅正电荷的分布决定了SSH链是否是拓扑。同样，我们显示由浆果连接定义的极化不能用于表征SSH模型2D概括的拓扑特性。
The Su-Schrieffer-Heeger(SSH) model has been widely used to study the topological property of 1D systems. It is claimed that there is fractional charge at the boundary of the nontrivial phase while none at that of trivial phase. However, this conclusion is in direct contradiction to the modern theory of polarization(MTP). We solve this paradox by showing that the polarization of SSH model depends only on the distribution of the positive charges and is irrelevant to the Zak phase defined in previous works. Thus the distribution of positive charges alone determines whether the SSH chain is topological or not. Similarly, we show the polarization defined by Berry connection can not be used to characterize topological property of a 2D generalization of SSH model.
