First-Principles Study of Half-Metallic and Magnetic Properties for the Heusler Alloys Fe2CrX (X = P, As, Sb, Bi)
First-Principles Study of Half-Metallic and Magnetic Properties for the Heusler Alloys Fe2CrX (X = P, As, Sb, Bi)
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DOI：
10.1007/s10948-014-2880-x
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发表时间：
2015-05-01
影响因子：
1.8
通讯作者：
Gao, Z. Y.
中科院分区：
文献类型：
--
作者：
Chen, B. S.;Li, Y. Z.;Gao, Z. Y.
通过基于密度泛函理论的第一性原理计算研究了 Heusler 合金 Fe2CrX (X = P、As、Sb、Bi) 的电子结构和磁性。计算表明，所有Fe2CrX合金都是半金属，在各自的平衡晶格常数下磁矩为3.00 mu（B），这与Slater-Pauling规则非常吻合。从Fe和Cr原子3d电子之间的杂化角度讨论了少数自旋态能隙的起源。这些合金的总磁矩主要由Cr原子的部分磁矩决定。当X原子变化时，Fe和Cr矩的变化相互补偿，保持总磁矩为整数。通过研究晶格常数对Fe2CrX合金半金属和磁性能的影响，发现Fe2CrSb和Fe2CrBi合金的半金属性能对晶格畸变最不敏感，当晶格从-9%膨胀到+3%时，可以获得100%的自旋极化。
The electronic structure and magnetism of the Heusler alloys Fe2CrX (X = P, As, Sb, Bi) have been investigated by first-principles calculations based on density functional theory. The calculations show that all Fe2CrX alloys are half-metals with a magnetic moment of 3.00 mu (B) at their respective equilibrium lattice constants, which is in good agreement with the Slater-Pauling rule. The origin of energy gap in the minority-spin states is discussed in terms of the hybridization among the 3d electrons of the Fe and Cr atoms. The total magnetic moments for these alloys are mainly determined by the partial moment of Cr atom. The change of Fe and Cr moments compensates each other and keeps the total magnetic moment as an integer when the X atom changes By investigating the effects of lattice constants on half-metallic and magnetic properties of Fe2CrX alloys, it is found that half-metallic properties of Fe2CrSb and Fe2CrBi alloys are the most insensitive to the lattice distortion and a 100 % spin polarization can be obtained when the lattice is expanded from -9 % to + 3 %.