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Itinerant ferromagnetism in half-metallic CoS_2

S. K. Kwon·S. J. Youn·B. I. Min
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Abstract

We have investigated electronic and magnetic properties of the pyrite-type CoS_2 using the linearized muffin-tin orbital (LMTO) band method. We have obtained the ferromagnetic ground state with nearly half-metallic nature. The half-metallic stability is studied by using the fixed spin moment method. The non-negligible orbital magnetic moment of Co 3d electrons is obtained as $μ_L = 0.06 μ_B$ in the local spin density approximation (LSDA). The calculated ratio of the orbital to spin angular momenta /< S_z > = 0.15 is consistent with experiment. The effect of the Coulomb correlation between Co 3d electrons is also explored with the LSDA + U method. The Coulomb correlation at Co sites is not so large, $U \lesssim 1$ eV, and so CoS_2 is possibly categorized as an itinerant ferromagnet. It is found that the observed electronic and magnetic behaviors of CoS_2 can be described better by the LSDA than by the LSDA + U.

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S. K. Kwon, S. J. Youn, B. I. Min. 2000-01-04. Itinerant ferromagnetism in half-metallic CoS_2. https://doi.org/10.1103/physrevb.62.357

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