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Supersymmetry and Theory of Heavy-Fermions

C. Pépin·M. Lavagna
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Abstract

We propose a new approach to the Kondo lattice in order to describe simultaneously the Kondo effect and the local magnetism. This approach relies on an original representation of the $S=1/2$ impurity spin in which the different degrees of freedom are represented by fermionic as well as bosonic variables. The magnetic instability is found at $J_c/D =0.67$ in definite improvement compared to usual fermionic mean- field theories. The dynamical susceptibility contains an inelastic peak in addition to the standard Lindhard-type Fermi liquid contribution. The Fermi surface sum rule includes $n_c+1$ states corresponding to large Fermi surfaces.

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C. Pépin, M. Lavagna. 1997-09-24. Supersymmetry and Theory of Heavy-Fermions. https://arxiv.org/abs/cond-mat/9709256

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