Second Wilson number from third-order perturbation theory for the symmetric single-impurity Kondo model at low temperatures

Kevin Bauerbach; Florian Gebhard

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arXiv · 2401.05979

Second Wilson number from third-order perturbation theory for the symmetric single-impurity Kondo model at low temperatures

Kevin Bauerbach·Florian Gebhard

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Abstract

We determine the impurity-induced free energy and the impurity-induced zero-field susceptibility of the symmetric single-impurity Kondo model from weak-coupling perturbation theory up to third order in the Kondo coupling at low temperatures and small magnetic fields. We reproduce the analytical structure of the zero-field magnetic susceptibility as obtained from Wilson's renormalization group method. This permits us to obtain analytically the first two Wilson numbers.

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Kevin Bauerbach, Florian Gebhard. 2024-01-11. Second Wilson number from third-order perturbation theory for the symmetric single-impurity Kondo model at low temperatures. https://arxiv.org/abs/2401.05979

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