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Strong Coupling Approach to the Supersymmetric Kondo Model

P. Coleman·C. Pepin·A. M. Tsvelik
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Abstract

We carry out the strong coupling expansion for the SU(N) Kondo model where the impurity spin is represented by a L-shaped Young tableau. Using second order perturbation theory around the strong coupling fixed point it is shown that when the antisymmetric component of the Young-tableau contains more than N/2 entries, the strong-coupling fixed point becomes unstable to a two-stage Kondo effect. By comparing the strong coupling results obtained here with the result using a supersymmetric large N expansion, we are also able to confirm the validity of the the supersymmetric formalism for mixed symmetry Kondo models.

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P. Coleman, C. Pepin, A. M. Tsvelik. 2000-07-07. Strong Coupling Approach to the Supersymmetric Kondo Model. https://doi.org/10.1016/s0550-3213(00)00419-3

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