Structural and superconducting properties ofMgB2−xBex

Structural and superconducting transitions in Mg1ÀxAlxB2

From systematic ab initio calculations for the alloy system Mg12xAlxB2, we find a strong tendency for the formation of a superstructure characterized by Al-rich layers. We also present a simple model, based on calculated energies and an estimate of the configurational entropy, which suggests that the alloy has two separate concentration regimes of phase separation, with critical points near x50...

Superconducting and structural properties of plasma sprayed Y-Ba-Cu-O layers deposited on metallic substrates*

The properties of plasma sprayed Y-Ba-Cu-O coatings deposited on metallic substrates are studied. Stainless steel, nickel steels and pure nickel are used as substrate. Y-Ba-Cu-O deposited on stainless steel and nickel steel reacts with the substrate. This interaction can be suppressed by using an yttria-stabilized zirconia (YsZ) diffusion barrier. However, after heat treatment the Y-Ba-Cu-O lay...

Structural and superconducting properties of orientation-ordered Y1Ba2Cu3O7-x films prepared by molecular-beam epitaxy.

HYDROSTATIC PRESSURE DEPENDENCE OF THE SUPERCONDUCTING AND STRUCTURAL PROPERTIES OF MgB2

The past ¿fteen years have witnessed some of the more memorable discoveries in the ninety-year-old ¿eld of superconductivity, including the high-AS oxides in 1986 [1], the alkali-doped fullerenes in 1991 [2], the charge-injected fullerenes in 2000 [3], and the binary compound MgB2 in January 2001 [4]. The discovery of superconductivity at such high temperatures (40 K) in the simple rc R-metal c...

Structural and thermodynamic properties of Alumina

We have investigated the electronic structure and thermodynamic properties of supercell of the -Al2O3 by first-principles calculation in framework of density functional theory (DFT) and full potential linearized augmented plane wave (FP-LAPW) with generalized gradient approximation (GGA) and by quasi-harmonic Debye model. Our calculated value for direct band gap of α-Al2O3 is 7.2 eV which i...