自由空间中一维W原子链的磁性  

Magnetism of Free Standing W Monoatomic Chains

作　　者：朱梓忠[1] 林秋宝[1] 

机构地区：[1]厦门大学物理学系,福建厦门361005

出　　处：《厦门大学学报（自然科学版）》2007年第6期774-777,共4页Journal of Xiamen University：Natural Science

基　　金：福建省自然科学基金(E0320001);集美大学科研基金(C50690)资助

摘　　要：应用基于密度泛函理论的第一原理方法,对自由空间中的一维W原子链的磁性进行了计算.得到了考虑自旋轨道相互作用的铁磁,反铁磁以及螺旋磁性结构的一维W原子链的原子磁矩随原子间距的变化及相应的磁学性质,并与不考虑自旋轨道相互作用的情况做了对比.结果发现,原子链的原子磁矩在原子间距的一个小变化范围内有个跃升,最终趋于单原子磁矩;与体材料时不同,稳定的一维W原子链具有磁性,而且反铁磁W原子链的相对稳定性高;轨道磁矩在有近邻原子作用时出现,且极化方向与自旋极化方向相反.最后,也对W一维原子链的电磁性质进行了讨论.By using the first-principles method based on the density functional theory with generalized gradient approximation,the magnetism of free standing W monoatomic chains have been studied. The magnetic moments as the function of the atomic distances with ferromagnetic,anti-ferromagnetic and spiral polarized states are obtained. The calculations have been performed with and without the spin-orbit coupling and the results are compared. The results show that the magnetic moment increases rapidly within a small region of atomic distances when the distance is larger than a certain value,and then approaches the value of a single atom. Different to the W bulk,the W chains are with magnetism and the anti-ferromagnetic states are more stable than the others. The orbital magnetic moment emerges when the inter-atomic exchange-correlation interaction emerges, and the orbital polarized direction is opposite to the spin polarized one. Also,the electric-magnetic properties of the freestanding W monoatomic chains are discussed.

关 键 词：原子链 磁性 自旋轨道相互作用 第一原理方法 

分 类 号：O482.5[理学—固体物理]