Fe或Cr单原子链填充Cu纳米管的稳定性与磁性

发布时间：2018-04-29 00:07

本文选题：过渡金属单原子链 + Cu纳米管　；参考：《复合材料学报》2017年11期

【摘要】：基于密度泛函理论框架下的第一性原理计算,系统地研究了过渡金属(TM)Fe或Cr线性单原子链填充(6,6)Cu纳米管(Fe@CuNT或Cr@CuNT)所形成复合结构的稳定性、磁性和电子特性。相对于孤立单原子链的单原子平均结合能,Fe@CuNT和Cr@CuNT复合结构的平均结合能大大增加,表明Cu纳米管的包裹使Fe或Cr单原子链的稳定性显著增强。外部Cu原子与内部TM原子间的化学键表现出非局域金属键特性,Fe@CuNT和Cr@CuNT复合结构的磁基态分别为为铁磁态和反铁磁态。对Fe@CuNT和Cr@CuNT复合结构内部Fe原子和Cr原子的自旋磁矩和轨道磁矩进行了计算。相对于自由单原子链,Fe@CuNT和Cr@CuNT复合结构的磁晶各向异性能显著增强,因此Fe@CuNT和Cr@CuNT复合结构可应用于超高密度磁存储中。Cu纳米管的包裹使Fe@CuNT复合结构的易磁化方向相对于自由Fe单原子链的易磁化方向发生了改变。此外,Fe@CuNT复合结构在费米能级处较高的自旋极化率使其可应用于自旋电子器件中。
[Abstract]:Based on the first-principle calculations based on density functional theory (DFT), the stability, magnetic and electronic properties of the composite structures formed by the transition metal TMFe or Cr linear monatomic chains filled with 6U 6U Cu nanotubes (Feb) are studied. Compared with the single atom chain, the average binding energy of the single atom binding energy is greatly increased, which indicates that the stability of Fe or Cr monatomic chains is greatly enhanced by the encapsulation of Cu nanotubes. The chemical bond between the external Cu atom and the inner TM atom exhibits the characteristics of non-local metal bond. The magnetic ground states of the Feb.CuNT and Cr@CuNT composite structures are ferromagnetic and antiferromagnetic respectively. The spin and orbital magnetic moments of Fe and Cr atoms in the composite structure of Fe@CuNT and Cr@CuNT are calculated. The magnetocrystalline anisotropy of the Feob-CuNT and Cr@CuNT composite structures is significantly enhanced compared with that of the free monatomic chain. Therefore, the encapsulation of Fe@CuNT and Cr@CuNT composite structure in ultrahigh density magnetic storage can change the magnetization direction of Fe@CuNT composite structure relative to that of free Fe monoatomic chain. In addition, the high spin-polarizability of Fe@ CuNT composite structure at Fermi level makes it possible to be used in spin electronic devices.
【作者单位】：宁夏大学物理与电子电气工程学院;陕西师范大学物理学与信息技术学院;
【基金】：基金项目:宁夏高等学校科学研究(NGY2016062)
【分类号】：TB383.1

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