Nature of magnetism in Ca$_3$Co$_2$O$_6$

Hua Wu; M. W. Haverkort; Z. Hu; D. I. Khomskii; L. H. Tjeng

doi:10.1103/PhysRevLett.95.186401

paper

Nature of magnetism in Ca $_{3}$ Co $_{2}$ O $_{6}$

arXiv:cond-mat/0504490 · doi:10.1103/PhysRevLett.95.186401

Abstract

We find using LSDA+U band structure calculations that the novel one-dimensional cobaltate Ca $_{3}$ Co $_{2}$ O $_{6}$ is not a ferromagnetic half-metal but a Mott insulator. Both the octahedral and the trigonal Co ions are formally trivalent, with the octahedral being in the low-spin and the trigonal in the high-spin state. The inclusion of the spin-orbit coupling leads to the occupation of the minority-spin $d_{2}$ orbital for the unusually coordinated trigonal Co, producing a giant orbital moment (1.57 $μ_{B}$ ). It also results in an anomalously large magnetocrystalline anisotropy (of order 70 meV), elucidating why the magnetism is highly Ising-like. The role of the oxygen holes, carrying an induced magnetic moment of 0.13 $μ_{B}$ per oxygen, for the exchange interactions is discussed.

arXiv comment5 pages, 4 figures, and 1 table

Nature of magnetism in Ca $_{3}$ Co $_{2}$ O $_{6}$

Abstract

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Nature of magnetism in Ca3​Co2​O6​

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Cited by in corpus (43)

Nature of magnetism in Ca $_{3}$ Co $_{2}$ O $_{6}$