Supersymmetric Approach to Heavy-Fermion Systems

TL;DR

This paper introduces a supersymmetric method for modeling heavy-Fermion systems, capturing both quasiparticle excitations and magnetic fluctuations, revealing new collective modes and Fermi surface properties.

Contribution

It develops a novel supersymmetric framework combining fermionic and bosonic spins to better describe heavy-Fermion phenomena.

Findings

Formation of a bosonic band within the hybridization gap

Strong renormalization of the density of states at the Fermi level

Fermi surface includes an additional state, n_c + 1

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.