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arXiv · 1711.10116

Chern Insulators on Singular Geometries

Ai-Lei He·Wei-Wei Luo·Yi-Fei Wang·Chang-De Gong
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Abstract

Topological quantum states have been proposed and investigated on two-dimensional flat surfaces or lattices with different geometries like the plane, cylinder and torus. Here, we study quantum anomalous Hall (QAH) or Chern insulator (CI) states on two-dimensional singular surfaces (such as conical and helicoid-like surfaces). Such singular geometries can be constructed based on the disk geometry and a defined unit sector with $n$-fold rotational symmetry. The singular geometry induces novel and intriguing features of CI/QAH states, such as in-gap and in-band core states, charge fractionalization, and multiple branches of edge excitations.

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Ai-Lei He, Wei-Wei Luo, Yi-Fei Wang, Chang-De Gong. 2017-11-28. Chern Insulators on Singular Geometries. https://doi.org/10.1103/physrevb.97.045126

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