Two-Dimensional Sigma-Hole Systems in Boron Layers: A First-Principles Study on Mg_{1-x}Na_xB_2 and Mg_{1-x}Al_xB_2

Abstract

We study two-dimensional sigma-hole systems in boron layers by calculating the electronic structures of Mg_{1-x}Na_xB_2 and Mg_{1-x}Al_xB_2. In Mg_{1-x}Na_xB_2, it is found that the concentration of sigma holes is approximately described by (0.8 + 0.8 x) * 10^{22} cm^{-3} and the largest attainable concentration is about 1.6 * 10^{22} cm^{-3} in NaB_2. In Mg_{1-x}Al_xB_2, on the other hand, it is found that the concentration of sigma holes is approximately described by (0.8 - 1.4 x) * 10^{22} cm^{-3} and sigma holes are disappeared at x of about 0.6. These relations can be used for experimental studies on the sigma-hole systems in these materials.

5 pages, 5 figures

Cited by in corpus (11)

• Intralayer Carbon Substitution in the MgB2 Superconductor
• The Tc amplification by quantum interference effects in diborides
• ${}^{11}$B and ${}^{27}$Al NMR spin-lattice relaxation and Knight shift study of Mg${}_{1-x}$Al${}_x$B${}_2$. Evidence for anisotropic Fermi surface
• Electron-phonon coupling and two-band superconductivity of Al- and C-doped MgB2
• A magnetization and ${}^{11}$B NMR study of Mg${}_{1-x}$Al${}_x$B${}_2$ superconductors
• Structural and Superconducting Transitions in Mg_{1-x}Al_{x}B_2
• Electronic Structure of B-2p State in AlB2 Single Crystal: Direct Observation ofpσand pπDensity of States
• Thermoelectric power of MgB${}_{2-x}$Be${}_x$
• Electronic Structures of MgB{${}_2$} under Uniaxial and Hydrostatic Compression
• Electronic structure of single-crystalline Mg${}_x$Al${}_{1-x}$B${}_2$ probed by x-ray diffraction multipole refinements and polarization-dependent x-ray absorption spectroscopy
• Is Delta_{pi}-gap-only superconductivity possible in Mg_{1-x}Al_{x}B_{2} and Mg(B_{1-y}C_{y})_{2} alloys?