Wei Juan, Kong Weixiang, Xiao Xiaoliang, Wang Rui, Gan Li-Yong, Fan Jing, Wu Xiaozhi
Institute for Structure and Function and Department of Physics, Chongqing University, Chongqing 400044, People's Republic of China.
Center for Computational Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China.
J Phys Chem Lett. 2022 Jun 23;13(24):5508-5513. doi: 10.1021/acs.jpclett.2c01087. Epub 2022 Jun 13.
Two-dimensional (2D) boron nitride (BN) is a promising candidate for aerospace materials due to its excellent mechanical and thermal stability properties. However, its unusually prominent band gap limits its application prospects. In this work, we report a gapless monolayer BN, -BN, which has four anisotropic Dirac cones in the first Brillouin zone exactly at the Fermi level. To further confirm the semimetallic character, the nontrivial topological properties are proven through the topologically protected edge states and the invariant non-zero . Additionally, the Young's modulus and Poisson ratio characterize the strong mechanical strength of -BN. Our theoretical predictions provide more possibilities for exploring the Dirac cone in BN, which will enhance the 2D boron derivative materials.
二维（2D）氮化硼（BN）因其优异的机械和热稳定性，是航空航天材料的一个有前途的候选材料。然而，其异常突出的带隙限制了其应用前景。在这项工作中，我们报告了一种无带隙的单层BN，即γ-BN，它在第一布里渊区的费米能级处恰好有四个各向异性的狄拉克锥。为了进一步证实其半金属特性，通过拓扑保护的边缘态和非零不变量证明了其非平凡的拓扑性质。此外，杨氏模量和泊松比表征了γ-BN的强机械强度。我们的理论预测为探索BN中的狄拉克锥提供了更多可能性，这将增强二维硼衍生材料。
