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The band structure of MgB$_{2}$ with different lattice constants

Xiangang Wan·Jinming Dong·Hongming Weng·D. Y. Xing
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Abstract

We report a detailed study of the electronic structure of the MgB$_{2}$ with different lattice constants by using the full-potential linearized augmented plane wave(FPLAPW) method. It is found that the lattice parameters have great effect on the $σ$ band of Boron. Our results indicate that increasing lattice constant along the {\it c} axis will increase the density of states(DOS) at the Fermi level, making the $σ$ band upward shift, and increasing hole number in the $σ$ band. So, the superconducting transition temperature T$_{c}$ will be raised correspondingly. Changing the lattice constant along {\it a} axis has an opposite effect to that of along {\it c} axis. Our result is in agreement with experiment. A possible way of searching for higher T$_{c}$ superconductor has been indicated, i.e., making MgB$_{2}$ to have longer {\it c} axis and shorter {\it a, b} axis by doping.

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Xiangang Wan, Jinming Dong, Hongming Weng, D. Y. Xing. 2001-10-22. The band structure of MgB$_{2}$ with different lattice constants. https://doi.org/10.1103/physrevb.65.012502

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