中国物理B ›› 2024, Vol. 33 ›› Issue (12): 127303-127303.doi: 10.1088/1674-1056/ad8a50

• • 上一篇    下一篇

Higher-order topological corner states and origin in monolayer LaBrO

Qing Wang(王庆)1,2 and Ning Hao(郝宁)1,†   

  1. 1 Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Anhui, Chinese Academy of Sciences, Hefei 230031, China;
    2 Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
  • 收稿日期:2024-09-29 修回日期:2024-10-22 接受日期:2024-10-23 出版日期:2024-12-15 发布日期:2024-12-15
  • 通讯作者: Ning Hao E-mail:haon@hmfl.ac.cn
  • 基金资助:
    This work was financially supported by the National Key R&D Program of China (Grant No. 2022YFA1403200), the National Natural Science Foundation of China (Grant Nos. 92265104, 12022413, and 11674331), the Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures (Grant No. JZHKYPT-2021-08), the CASHIPS Director’s Fund (Grant No. BJPY2023A09), the “Strategic Priority Research Program (B)” of the Chinese Academy of Sciences (Grant No. XDB33030100), Anhui Provincial Major S&T Project (Grant No. s202305a12020005), the Major Basic Program of Natural Science Foundation of Shandong Province (Grant No. ZR2021ZD01), and the High Magnetic Field Laboratory of Anhui Province (Grant No. AHHM-FX-2020-02).

Higher-order topological corner states and origin in monolayer LaBrO

Qing Wang(王庆)1,2 and Ning Hao(郝宁)1,†   

  1. 1 Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Anhui, Chinese Academy of Sciences, Hefei 230031, China;
    2 Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
  • Received:2024-09-29 Revised:2024-10-22 Accepted:2024-10-23 Online:2024-12-15 Published:2024-12-15
  • Contact: Ning Hao E-mail:haon@hmfl.ac.cn
  • Supported by:
    This work was financially supported by the National Key R&D Program of China (Grant No. 2022YFA1403200), the National Natural Science Foundation of China (Grant Nos. 92265104, 12022413, and 11674331), the Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures (Grant No. JZHKYPT-2021-08), the CASHIPS Director’s Fund (Grant No. BJPY2023A09), the “Strategic Priority Research Program (B)” of the Chinese Academy of Sciences (Grant No. XDB33030100), Anhui Provincial Major S&T Project (Grant No. s202305a12020005), the Major Basic Program of Natural Science Foundation of Shandong Province (Grant No. ZR2021ZD01), and the High Magnetic Field Laboratory of Anhui Province (Grant No. AHHM-FX-2020-02).

摘要: Intrinsic higher-order topological insulators driven solely by orbital coupling are rare in electronic materials. Here, we propose that monolayer LaBrO is an intrinsic two-dimensional second-order topological insulator. The generalized second-order topological phase arises from the coupling between the 5d orbital of the La atom and the 2p orbital of the O atom. The underlying physics can be thoroughly described by a four-band generalized higher-order topological model. Notably, the edge states and corner states of monolayer LaBrO exhibit different characteristics in terms of morphology, number, and location distribution under different boundary and nanocluster configurations. Furthermore, the higher-order topological corner states of monolayer LaBrO are robust against variations in spin-orbit coupling and different values of Hubbard $U$. This provides a material platform for studying intrinsic 2D second-order topological insulators.

关键词: second order topological insulator, first-principles calculations, higher order topological model, zero-dimensional corner state

Abstract: Intrinsic higher-order topological insulators driven solely by orbital coupling are rare in electronic materials. Here, we propose that monolayer LaBrO is an intrinsic two-dimensional second-order topological insulator. The generalized second-order topological phase arises from the coupling between the 5d orbital of the La atom and the 2p orbital of the O atom. The underlying physics can be thoroughly described by a four-band generalized higher-order topological model. Notably, the edge states and corner states of monolayer LaBrO exhibit different characteristics in terms of morphology, number, and location distribution under different boundary and nanocluster configurations. Furthermore, the higher-order topological corner states of monolayer LaBrO are robust against variations in spin-orbit coupling and different values of Hubbard $U$. This provides a material platform for studying intrinsic 2D second-order topological insulators.

Key words: second order topological insulator, first-principles calculations, higher order topological model, zero-dimensional corner state

中图分类号:  (Electronic structure of nanoscale materials and related systems)

  • 73.22.-f
31.15.es (Applications of density-functional theory (e.g., to electronic structure and stability; defect formation; dielectric properties, susceptibilities; viscoelastic coefficients; Rydberg transition frequencies)) 73.20.At (Surface states, band structure, electron density of states) 02.40.-k (Geometry, differential geometry, and topology)