Effective indirect multi-site spin-spin interactions in the s-d(f) model

K. K. Komarov; D. M. Dzebisashvili

doi:10.1016/j.jmmm.2016.12.075

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arXiv · 1609.05603

Effective indirect multi-site spin-spin interactions in the s-d(f) model

K. K. Komarov·D. M. Dzebisashvili

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Abstract

Using the diagram technique for Matsubara Green's functions it is shown that the dynamics of the localized spin subsystem in the s-d(f) model can be described in terms of an effective spin model with multi-site spin-spin interactions. An exact representation of the action for the effective purely spin model is derived as an infinite series in powers of s-d(f) exchange interaction $J$. The indirect interactions of the 2-nd, 3-rd and 4-th order are discussed.

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K. K. Komarov, D. M. Dzebisashvili. 2016-09-19. Effective indirect multi-site spin-spin interactions in the s-d(f) model. https://doi.org/10.1016/j.jmmm.2016.12.075

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