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Supersymmetric Approach to Heavy-Fermion Systems

C. Pepin·M. Lavagna
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Abstract

We present a new supersymmetric approach to the Kondo lattice model in order to describe simultaneously the quasiparticle excitations and the low-energy magnetic fluctuations in heavy-Fermion systems. This approach mixes the fermionic and the bosonic representation of the spin following the standard rules of superalgebra. Our results show the formation of a bosonic band within the hybridization gap reflecting the spin collective modes. The density of states at the Fermi level is strongly renormalized while the Fermi surface sum rule includes $n_{c}+1$ states. The dynamical susceptibility is made of a Fermi liquid superimposed on a localized magnetism contribution.

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C. Pepin, M. Lavagna. 1998-11-26. Supersymmetric Approach to Heavy-Fermion Systems. https://doi.org/10.1007/s002570050369

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