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arXiv · 1705.00257

Two-dimensional boron on Pb (110) surface

Xin-Ling He·Xiao-Ji Weng·Yue Zhang·Zhisheng Zhao·Zhenhai Wang·Bo Xu·Artem R. Oganov·Yongjun Tian·Xiang-Feng Zhou·Hui-Tian Wang
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Abstract

We simulate boron on Pb(110) surface by using ab initio evolutionary methodology. Interestingly, the two-dimensional (2D) Dirac Pmmn boron can be formed because of good lattice matching. Unexpectedly, by increasing the thickness of 2D boron, a three-bonded graphene-like structure (P2_1/c boron) was revealed to possess double anisotropic Dirac cones. It is 20 meV/atom lower in energy than the Pmmn structure, indicating the most stable 2D boron with particular Dirac cones. The puckered structure of P2_1/c boron results in the peculiar Dirac cones, as well as substantial mechanical anisotropy. The calculated Young's modulus is 320 GPa.nm along zigzag direction, which is comparable with graphene.

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Xin-Ling He, Xiao-Ji Weng, Yue Zhang, Zhisheng Zhao, Zhenhai Wang, Bo Xu, Artem R. Oganov, Yongjun Tian, Xiang-Feng Zhou, Hui-Tian Wang. 2017-04-30. Two-dimensional boron on Pb (110) surface. https://arxiv.org/abs/1705.00257

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