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arXiv · 1301.4386

Diagrammatic theory for twofold degenerate Anderson impurity model

V. A. Moskalenko·L. A. Dohotaru·D. F. Digor·I. D. Cebotari
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Abstract

The twofold degenerate Anderson impurity model [1-4] is investigated and the strong electronic correlations of d-electrons of impurity ion are taken into account by elaborating suitable diagram technique. We discuss the properties of the Slater-Kanamori model [2-4] of d-impurity electrons. After finding the eigenfunctions and eigenvalues of all 16 local states, we determine the local one-particle propagator. Then we construct the perturbation theory around the atomic limit of the impurity ion and obtain the Dyson type equation for the renormalized one-particle propagator. Diagrammatic theory has been developed and correlation function determined. Special diagrammatic approximation was discussed and summation of diagram has been considered.

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V. A. Moskalenko, L. A. Dohotaru, D. F. Digor, I. D. Cebotari. 2013-01-18. Diagrammatic theory for twofold degenerate Anderson impurity model. https://doi.org/10.1007/s11232-014-0133-6

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