Electronic, structural, and magnetic properties of the quaternary Heusler alloy NiCoMnZ (Z=Al, Ge, and Sn)

• Published in: Journal of magnetism and magnetic materials Vol. 377; pp. 220 - 225
• Main Authors: Halder, Madhumita, Mukadam, M.D., Suresh, K.G., Yusuf, S.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2015
• Subjects: Aluminum; Electronics; Ferromagnetism; Germanium; Heusler alloys; Magnetic properties; Mathematical analysis; Polarization; Tin
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2014.10.107

The electronic, magnetic, and structural properties of the Heusler alloys NiCoMnZ (Z=Al, Ge, and Sn) have been investigated both theoretically and experimentally. NiCoMnGe and NiCoMnSn have ordered cubic Heusler structure (with a possible disorder between Ni and Co), while NiCoMnAl has a B2 type disordered Heusler structure with random occupancy between Mn and Al atom at their crystallographic sites. Electronic structure calculation shows that NiCoMnGe and NiCoMnSn are normal ferromagnets, whereas NiCoMnAl is nearly half metallic (~100% spin polarization) in nature with its magnetic moment close to an integer value following the Slater–Pauling rule. Ab-initio calculations show ~56% and ~60% spin polarization for NiCoMnGe and NiCoMnSn, respectively. Magnetization measurements show all the three compounds have a high Curie temperature (>583K). •Electronic, magnetic, and structural properties of Heusler alloys NiCoMnZ (Z=Al, Ge, and Sn) have been investigated.•NiCoMnGe and NiCoMnSn are normal ferromagnets, while NiCoMnAl is nearly half metallic.•All the three compounds have a high Curie temperature.•NiCoMnGe and NiCoMnSn have ordered cubic structure; while NiCoMnAl has a B2 type disordered structure.