著者

Okutani Makoto Jo Takeo

出版者

一般社団法人日本物理学会

雑誌

Journal of the Physical Society of Japan (ISSN:00319015)

巻号頁・発行日

vol.69, no.2, pp.598-606, 2000-02-15

参考文献数

46

被引用文献数

3

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The spin (Ms) and orbital magnetic moments (Mo) of a Co atom arecalculated for various superlattices of Co atoms in fcc Pd or Cu matrixon the basis of the tight-binding model including s, p and d orbits,where the intraatomic multipole interaction between d electrons is takeninto account with the Hartree-Fock approximation. A test calculation forpure Fe, Co and Ni with use of parameters obtained by fitting withthe first-principles calculation shows that the method well describes theratio Mo/Ms. Two types of enhancement of Mo of the Co atom insuperlattices are proposed based on a semi-quantitative calculation withassuming ferromagnetism. In the Pd matrix, the enhancement is shown toarise from the increase of the lattice parameter, which causes the narrowing of3d density of states; the atomic environment of a Co atom in the matrix, i.e., the numbers ofneighboring Co or Pd atoms are the minor effect. In the Cu matrix, on the otherhand, the difference in the effective hybridization in the 3d statebetween Co-Co and Co-Cu pairs mainly determines the extent of the narrowing of Co 3d states andtherefore the extent of the enhancement. If all the nearest neighbors of a Co atom are occupied by Cu atoms, it isshown that Mo can be comparable to Ms.