Half-metallic ferromagnetism in wurtzite MC ( M = Ca , Sr, Ba and Mg)

• Published in: Solid state communications 2009-03, Vol.149 (9), p.387-392
• Main Authors: Zhang, Chang-wen, Yan, Shi-shen
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Electronic structure; D. Half-metallic ferromagnetism; E. First-principles calculation; Exact sciences and technology; Magnetic properties and materials; Nonmetallic ferromagnetic materials; Physics; Studies of specific magnetic materials
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2008.12.012

The first-principles full-potential linearized augmented plane-wave method within density-functional theory is used to investigate electronic structure and magnetism of wurtzite (WZ) crystal structure MC (M=Ca,Sr,Ba and Mg). It is shown that the WZ CaC, SrC and BaC are half-metallic ferromagnets with a magnetic moment of 2 μ B per formula unit, whereas MgC shows the metallic character. The half-metallicity is also found to be robust with respect to the lattice compression and is maintained up to the lattice constant contraction of 12%, 21%, and 8% for WZ CaC, SrC and BaC, respectively. The large HM gaps (0.54–0.81 eV) and robustness of half-metallicity with respect to the lattice change make these materials possible candidates for spin injection in spintronic devices.