English

Topological Edge States Induced by Zak's Phase in A3B Monolayers

Mesoscale and Nanoscale Physics 2019-03-27 v1

Abstract

In crystalline systems, charge polarization is related to Zak's phase determined by bulk band topology. Nontrivial charge polarization induces robust edge states accompanied with fractional charge. In Su-Schrieffer-Heeger (SSH) model, it is known that the strong modulation of electron hopping causes nontrivial charge polarization even in the presence of inversion symmetry. Here, we consider a bi-atomic honeycomb lattice to introduce such strong modulation, i.e. A3_3B sheet. By tuning hopping ratio and onsite potential difference between A and B atoms, we show that topological phase transition characterized by Zak's phase occurs. Furthermore, we propose that C3_3N and BC3_3 are the possible realistic materials on the basis of first-principles calculations. Both of them display topological edge states induced by Zak's phase without spin-orbital couplings and external fields unlike conventional topological insulators.

Keywords

Cite

@article{arxiv.1902.02485,
  title  = {Topological Edge States Induced by Zak's Phase in A3B Monolayers},
  author = {Tomoaki Kameda and Feng Liu and Sudipta Dutta and Katsunori Wakabayashi},
  journal= {arXiv preprint arXiv:1902.02485},
  year   = {2019}
}