Idris Hamid Bhat

Transport properties of spin polarised quaternary CoMnVAs alloy

The electronic structure and transport properties of CoMnVAs quaternary Heusler compound has been investigated first time by using the density functional theory. The material was found half-metallic ferromagnet in F-43m structure. Positive values of the different elastic parameters also confirm its structural stability. Present study predicts an energy band gap of 0.55 eV in localized minority spin channel at an equilibrium lattice constant of 5.75A. Post-DFT treatment predicts this material to be an n-type thermoelectric along with a high Seebeck coefficient of -45μV K-1 at room temperature.

Ferromagnetism in half-metallic quaternary FeVTiAl Heusler compound

The electronic structure and magnetic properties of FeVTiAl quaternary Heusler alloy have been investigated within the density functional theory framework. The material was found completely spin-polarized half-metallic Ferromagnet in the ground state with F-43m structure. The structural stability was further confirmed by calculating different elastic constants in the cubic phase. Present study predicts an energy band gap of 0.72 eV calculated in localized minority spin channel at an equilibrium lattice parameter of 6.0A. The calculated total spin magnetic moment of 2 µB/f.u. is in agreement with the Slater-Pauling rule for full Heusler alloys.

Variation of magnetism and half-metallicity in Ru2VSi with lattice expansion

Full-potential linearized augmented plane wave method has been employed to investigate the electronic and magnetic properties of Ru2VSi Heusler alloy at optimized lattice parameter and in expanded lattice. Present computations predict that Ru2VSi has a ferromagnetic ground state with an optimized lattice constant 5.952 A. The compound in ambient conditions was found to have metallic character. However, increased value of lattice parameter induces 100% spin-polarization in the material at Fermi energy. Further, the band gap tends to increase and the material behaves as pure half-metallic at an increased value of lattice constant.

Study of Ru2VGe and Ru2VSb: High-spin polarized and half-metallic Heusler alloys

Electronic and magnetic properties of Ru2VGe and Ru2VSb have been investigated by ab-initio. The optimized equilibrium lattice parameters were found to be 6.032 A for Ru2VGe and 6.272 A for Ru2VSb. Both the materials have ferromagnetic ground states and V mainly contributes to the magnetic properties in these materials. The highly spin-polarized half-metallic materials have integral magnetic moments of 1.0 µ B for Ru2VGe and 2.0 µ B for Ru2VSb with an energy gap of 0.095 eV for Ru2VGe and 0.186 eV for Ru2VSb in the spin-down channel.

FPLAPW approach to high pressure mechanical and thermal behavior of HfN

We have investigated the mechanical and thermo-physical properties of HfN in B1 and high pressure B2 phases by means of full-potential linearized augmented plane wave method. The calculated data is in good agreement with the experiments. HfN is observed to be mechanically stable in B1 as well as in B2 phases and show brittleness in B1 phase whereas ductility in B2 phase. Calculated values for the thermo-physical properties need experimental validation in both the phases.

Structural and magnetic stability of Fe2NiSi

Full-potential ab-initio calculations in the stable F-43m phase have been performed to investigate the structural and magnetic properties of Fe2NiSi inverse Heusler alloys. The spin magnetic moment distributions show that present material is ferromagnetic in stable F-43m phase. Further, spin resolved electronic structure calculations show that the discrepancy in magnetic moments of Fe-I and Fe-II depend upon the hybridization of Fe with the main group element. It is found that the main group electron concentration is predominantly responsible in establishing the magnetic properties, formation of magnetic moments and the magnetic order for present alloy.