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Flow-Equation method for a superconductor with magnetic correlations

C. P. Moca·M. Crisan·I. Tifrea
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Abstract

The flow equation method has been used to calculate the energy of single impurity in a superconductor for the Anderson model with $U \neq 0$. We showed that the energy of the impurity depends only of the $Δ^{2}_{R}$ (renormalized order parameter) which depends on the renormalized Hubbard repulsion$U^R$. For a strong Hubbard repulsion $U^R = U$ and $Δ^R = Δ^I$ the effect of the $s-d$ interactions are nonrelevant, a result which is expected for this model.

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C. P. Moca, M. Crisan, I. Tifrea. 1998-06-26. Flow-Equation method for a superconductor with magnetic correlations. https://arxiv.org/abs/cond-mat/9806326

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