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A first-principles study of MgB2 (0001) surfaces

Zhenyu Li·Jinlong Yang·J. G. Hou·Qingshi Zhu
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Abstract

We report self-consistent {\it ab initio} calculations of structural and electronic properties for the B- and Mg-terminated MgB$_{2}$ (0001) surfaces. We employ ultra-soft pseudopotentials and plane wave basis sets within the generalized gradient approximation. The surface relaxations are found to be small for both B- and Mg-terminated surfaces. For the B-terminated surface, both B $σ$ and $π$ surface bands appear, while only one B $π$ surface band exists near the Fermi level for the Mg-terminated surface. The superconductivity of the MgB$_2$ surfaces is discussed. The work function is predicted to be 5.95 and 4.25 eV for the B- and Mg-terminated surfaces respectively. The simulated scanning tunneling microscopy images of the surfaces are not sensitive to the sign and value of the bias voltages, but depend strongly on the tip-sample distance. An image reversal is predicted for the Mg-terminated surface.

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Zhenyu Li, Jinlong Yang, J. G. Hou, Qingshi Zhu. 2001-06-28. A first-principles study of MgB2 (0001) surfaces. https://doi.org/10.1103/physrevb.65.100507

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