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Role of Boron p-Electrons and Holes in Superconducting MgB2, and other Diborides: A Fully-Relaxed, Full-Potential Electronic Structure Study

Prabhakar P. Singh
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Abstract

We present the results of fully-relaxed, full-potential electronic structure calculations for the new superconductor MgB2, and BeB2, NaB2, and AlB2, using density-functional-based methods. Our results described in terms of (i) density of states (DOS), (ii) band-structure, and (iii) the DOS and the charge density around the Fermi energy EF, clearly show the importance of B p-band for superconductivity. In particular, we show that around EF, the charge density in MgB2, BeB2 and NaB2 is planar and is associated with the B plane. For BeB2 and NaB2, our results indicate qualitative similarities but significant quantitative differences in their electronic structure due to different lattice constants a and c.

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Prabhakar P. Singh. 2001-04-28. Role of Boron p-Electrons and Holes in Superconducting MgB2, and other Diborides: A Fully-Relaxed, Full-Potential Electronic Structure Study. https://doi.org/10.1103/physrevlett.87.087004

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