中国物理B ›› 2020, Vol. 29 ›› Issue (5): 57303-057303.doi: 10.1088/1674-1056/ab7e9e

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Seeing Dirac electrons and heavy fermions in new boron nitride monolayers

Yu-Jiao Kang(康玉娇), Yuan-Ping Chen(陈元平), Jia-Ren Yuan(袁加仁), Xiao-Hong Yan(颜晓红), Yue-E Xie(谢月娥)   

  1. 1 School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, China;
    2 Faculty of Science, Jiangsu University, Zhenjiang 212013, China
  • 收稿日期:2020-02-15 修回日期:2020-03-05 出版日期:2020-05-05 发布日期:2020-05-05
  • 通讯作者: Yue-E Xie E-mail:yueex@ujs.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11874314) and the Natural Science Foundation of Hunan Province, China (Grant No. 2018JJ2377).

Seeing Dirac electrons and heavy fermions in new boron nitride monolayers

Yu-Jiao Kang(康玉娇)1,2, Yuan-Ping Chen(陈元平)1,2, Jia-Ren Yuan(袁加仁)2, Xiao-Hong Yan(颜晓红)2, Yue-E Xie(谢月娥)1,2   

  1. 1 School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, China;
    2 Faculty of Science, Jiangsu University, Zhenjiang 212013, China
  • Received:2020-02-15 Revised:2020-03-05 Online:2020-05-05 Published:2020-05-05
  • Contact: Yue-E Xie E-mail:yueex@ujs.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11874314) and the Natural Science Foundation of Hunan Province, China (Grant No. 2018JJ2377).

摘要: Most three-dimensional (3D) and two-dimensional (2D) boron nitride (BN) structures are wide-band-gap insulators. Here, we propose two BN monolayers having Dirac points and flat bands, respectively. One monolayer is named as 5-7 BN that consists of five- and seven-membered rings. The other is a Kagome BN made of triangular boron rings and nitrogen dimers. The two structures show not only good dynamic and thermodynamic stabilities but also novel electronic properties. The 5-7 BN has Dirac points on the Fermi level, indicating that the structure is a typical Dirac material. The Kagome BN has double flat bands just below the Fermi level, and thus there are heavy fermions in the structure. The flat-band-induced ferromagnetism is also revealed. We analyze the origination of the band structures by partial density of states and projection of orbitals. In addition, a possible route to experimentally grow the two structures on some suitable substrates such as the PbO2 (111) surface and the CdO (111) surface is also discussed, respectively. Our research not only extends understanding on the electronic properties of BN structures, but also may expand the applications of BN materials in 2D electronic devices.

关键词: boron nitride, Dirac fermion, flat band, ferromagnetism

Abstract: Most three-dimensional (3D) and two-dimensional (2D) boron nitride (BN) structures are wide-band-gap insulators. Here, we propose two BN monolayers having Dirac points and flat bands, respectively. One monolayer is named as 5-7 BN that consists of five- and seven-membered rings. The other is a Kagome BN made of triangular boron rings and nitrogen dimers. The two structures show not only good dynamic and thermodynamic stabilities but also novel electronic properties. The 5-7 BN has Dirac points on the Fermi level, indicating that the structure is a typical Dirac material. The Kagome BN has double flat bands just below the Fermi level, and thus there are heavy fermions in the structure. The flat-band-induced ferromagnetism is also revealed. We analyze the origination of the band structures by partial density of states and projection of orbitals. In addition, a possible route to experimentally grow the two structures on some suitable substrates such as the PbO2 (111) surface and the CdO (111) surface is also discussed, respectively. Our research not only extends understanding on the electronic properties of BN structures, but also may expand the applications of BN materials in 2D electronic devices.

Key words: boron nitride, Dirac fermion, flat band, ferromagnetism

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

  • 73.22.-f
73.43.Cd (Theory and modeling) 71.15.Mb (Density functional theory, local density approximation, gradient and other corrections)