Magnetic properties and temperature-dependent half-metallicity of Co2Mn(Ga(1-x)Z(x)) (Z = Si, Ge, Sn) from first-principles calculation

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	Magnetic properties and temperature-dependent half-metallicity of Co2Mn(Ga(1-x)Z(x)) (Z = Si, Ge, Sn) from first-principles calculation
	H. B. Luo; Q. M. Hu; C. M. Li; B. Johansson; L. Vitos; R. Yang
	2013
发表期刊	Journal of Physics-Condensed Matter
ISSN	0953-8984
卷号	25 期号:15
摘要	Using the first-principles exact muffin-tin orbitals method in combination with the coherent potential approximation, we investigated the magnetic properties, exchange interactions, and temperature-dependent half-metallicity of the Co2Mn(Ga(1-x)Z(x)) (Z = Si, Ge, Sn) alloys. The total magnetic moment follows perfectly a previously proposed Slater-Pauling relation, i.e., mu(0) = N-t - 24, with N-t being the number of valence electrons. The Co-Mn and Co1-Co2 (inter-sublattice) interactions are dominated by direct exchange, whereas the Co1-Co1 (intra-sublattice) interaction is characterized by superexchange. The Mn-Mn exchange interaction in Co2MnGa is of long-ranged RKKY-type. However, the Mn-Mn exchange interactions in Co(2)MnZ are relatively localized and can be attributed to superexchange. The Co-Mn, Co1-Co2 and Co1-Co1 total exchange interactions increase with x, whereas the Mn-Mn total exchange interactions show convex behavior. The calculated Curie temperature (T-C) increases with x. The ability of Z to enhance T-C follows the sequence of Si > Ge > Sn, in agreement with the experimental findings. The temperature dependence of the spin polarization at the Fermi level [P(T)] is investigated based on the disordered local moment model. P(T) drops abruptly at temperatures much lower than T-C. At temperatures higher than 200 K, the composition with higher TC generally corresponds to larger P(T).
部门归属	[luo, hu-bin ; hu, qing-miao ; li, chun-mei ; yang, rui] chinese acad sci, shenyang natl lab mat sci, inst met res, shenyang 110016, peoples r china. [johansson, borje ; vitos, levente] royal inst technol, dept mat sci & engn, se-10044 stockholm, sweden. [johansson, borje ; vitos, levente] uppsala univ, div mat theory, dept phys & astron, se-751210 uppsala, sweden. [vitos, levente] wigner res ctr phys, res inst solid state phys & opt, h-1525 budapest, hungary. ; luo, hb (reprint author), chinese acad sci, shenyang natl lab mat sci, inst met res, 72 wenhua rd, shenyang 110016, peoples r china. ; hbluo@imr.ac.cn ; qmhu@imr.ac.cn
关键词	Exchange Interactions Heusler Alloys Ferromagnetic Metals Tunnel-junctions Potential Model Magnetoresistance Crystal States
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语种	英语
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/71395
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	H. B. Luo,Q. M. Hu,C. M. Li,et al. Magnetic properties and temperature-dependent half-metallicity of Co2Mn(Ga(1-x)Z(x)) (Z = Si, Ge, Sn) from first-principles calculation[J]. Journal of Physics-Condensed Matter,2013,25(15).
APA	H. B. Luo,Q. M. Hu,C. M. Li,B. Johansson,L. Vitos,&R. Yang.(2013).Magnetic properties and temperature-dependent half-metallicity of Co2Mn(Ga(1-x)Z(x)) (Z = Si, Ge, Sn) from first-principles calculation.Journal of Physics-Condensed Matter,25(15).
MLA	H. B. Luo,et al."Magnetic properties and temperature-dependent half-metallicity of Co2Mn(Ga(1-x)Z(x)) (Z = Si, Ge, Sn) from first-principles calculation".Journal of Physics-Condensed Matter 25.15(2013).