New Class of 3D Topological Insulator in Double Perovskite

Shu Ting Pi, Hui Wang, Jeongwoo Kim, Ruqian Wu, Yin Kuo Wang, Chi Ken Lu

研究成果: 雜誌貢獻文章

11 引文 斯高帕斯(Scopus)

摘要

We predict a new class of 3D topological insulators (TIs) in which the spin-orbit coupling (SOC) can more effectively generate band gap. Band gap of conventional TI is mainly limited by two factors, the strength of SOC and, from electronic structure perspective, the band gap when SOC is absent. While the former is an atomic property, the latter can be minimized in a generic rock-salt lattice model in which a stable crossing of bands at the Fermi level along with band character inversion occurs in the absence of SOC. Thus large-gap TIs or TIs composed of lighter elements can be expected. In fact, we find by performing first-principles calculations that the model applies to a class of double perovskites A 2 BiXO 6 (A = Ca, Sr, Ba; X = Br, I) and the band gap is predicted up to 0.55 eV. Besides, surface Dirac cones are robust against the presence of dangling bond at boundary.

原文英語
頁(從 - 到)332-339
頁數8
期刊Journal of Physical Chemistry Letters
8
發行號2
DOIs
出版狀態已發佈 - 2017 一月 19

    指紋

ASJC Scopus subject areas

  • Materials Science(all)
  • Physical and Theoretical Chemistry

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