First Principles Study of Fe based Full Heusler Alloy

Kumari Seema, Mandeep Kaur, Ranjan Kumar

Abstract


The electronic structure of Fe-based quaternary Heusler compounds Fe2CoZ (Z=Ga, Ge) is calculated by first-principles density functional theory. Structural optimization is performed for two possible structures: Hg2CuTi-type and Cu2MnAl-type structures of Fe2CoZ. We found that Hg2CuTi-type structure is energetically more favorable than Cu2MnAl-type structure. The calculated equilibrium lattice constant is 5.812Ã… and 5.75Ã… respectively for Ga and Ge based alloy. The calculations reveal that Fe2CoGa material exhibit 100% spin-polarization whereas Fe2CoGe has 62% spin-polarization. The value of magnetic moment for Fe2CoGa and Fe2CoGe is 5.72mB, 4.96mB respectively

Full Text:

PDF

References


Galanakis I, Mavropoulos P, Dederichs P H, Electronic structure and Slater–Pauling behaviour in half-metallic Heusler alloys calculated from first principles, J. Phys. D 2006, 39, 765–775.

Kandpal H C, Fecher G H, and Felser C, Calculated electronic and magnetic properties of the half-metallic, transition metal based Heusler compounds, J. Phys. D 2007, 40 1507 –1523.

DeGroot R A, Mueller F M, van Engen P G, and Buschow K H J, New Class of Materials: Half-Metallic Ferromagnets, Phys. Rev. Lett. 1983, 50, 2024- 2027.

Kübler J, Williams A R, and Sommers C B, Formation and coupling of magnetic moments in Heusler alloys, Phys. Rev. B 1983, 28, 1745 –1755.

Wurmehl S, Kandpal H C, Fecher G H, and Felser C, Valence electron rules for prediction of half-metallic compensated-ferrimagnetic behaviour of Heusler compounds with complete spin polarization, J. Phys.: Condens. Matter 2006, 18, 6171 –6181.

Jung D, Koo H J, and Whangbo M H, Study of the 18-electron band gap and ferromagnetism in semi-Heusler compounds by non-spin-polarized electronic band structure calculations, J. Mol. Struct. (Theochem) 2000, 527, 113-119.

Wernick J H, Hull G W, Geballe T H, Bernadini J E, and Waszczak J V, Superconductivity in ternary Heusler intermetallic compounds, Mater. Lett. 1983, 2, 90-92.

Zayak A T, Entel P, Enkovaara J, Ayuela A, and Nieminen R M, First-principles investigation of phonon softenings and lattice instabilities in the shape-memory system Ni2MnGa, Phys. Rev. B 2003, 68, 132402-1 - 132402-4.

Soler J M, Artacho E, Julian D, Gale J D, Garc A, Junquera J, Ordejon P and Sanchez-Portal D, The SIESTA method for ab initio order-N materials simulation, J. Phys.: Condens. Matter 2002, 14, 2745–2779.

Perdew J P, Burke K, and Erzerhof M, Generalized Gradient Approximation Made Simple, Phys. Rev. Lett. 1996, 77, 3865-3868.

Troullier N, and Martins J L, Efficient pseudopotentials for plane-wave calculations, Phys. Rev. B 1991, 43, 1993-2006.

Luo H, Zhu Z, Liu G, Xu S, Wu G, Liu H, Qu J, Li Y, Prediction of half-metallic properties for the Heusler alloys Mn2CrZ (Z=Al, Ga, Si, Ge, Sb): A first-principles study, J. Magn. Magn. Mater. 1944, 320, 421.

Murnaghan F D, The Compressibility of Media under Extreme Pressures, Proc. Natl. Acad. Sci. U. S. A. 1944, 30, 244–247.

Webster P J and Ziebeck K. R. A., Magnetic and chemical order in Heusler alloys containing cobalt and titanium, J. Phys. Chem. Solids. 1973, 34, 1647-1656.

Kulkova S E, Sergey V. E., T. Kakeshita T. Kulkov S S and Rudenski G E, The Electronic Structure and Magnetic Properties of Full- and Half-Heusler Alloys, Materials Transactions 2006, 47, 599-606.

Gasi T, Ksenofontov V, Kiss J, Chadov S, Nayak A K, Nicklas M, Winterlik J, Schwall M, Klaer P, Adler P and Felser C, New iron-based Heusler compounds Fe2YZ: Comparison with theoretical predictions of the crystal structure and magnetic properties, arXiV 1301.1988

Ren Z, Li S T, and Lu H Z, Structure and magnetic properties of Fe2CoGe synthesized by ball-milling, Physica B 2010, 405, 2840-2843.

Galanakis I, Dederichs P H, and Papanikolaou N, Slater-Pauling behavior and origin of the half-metallicity of the full-Heusler alloys, Phys. Rev. B 2002, 66, 174429-1 - 174429-9.




Bookmark and Share