Theory of Itinerant Ferromagnets with Localized-Moment Characteristics: Two-Center Coupling in the Functional-Integral Scheme
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چکیده
The coupling between two magnetic centers in a band is discussed within the framework of the functional-integral scheme. The model used is the single-orbital Hubbard model with Coulomb repulsion only on the two magnetic sites. In lowest approximation, antiferromagnetic Ising coupling is obtained when the moments are nearest neighbors. When the moments are far apart, Ruderman-Kittel-Kasuya-Yosida coupling is the most important of several terms.
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تاریخ انتشار 2011