Strongly Inhomogeneous Phases and Non-Fermi Liquid Behavior in Randomly Depleted Kondo Lattices

TL;DR

This paper explores how random depletion of local moments in Kondo lattices creates inhomogeneous states with non-Fermi liquid behavior, relevant to certain heavy-fermion compounds.

Contribution

It introduces a theoretical framework for understanding inhomogeneous phases and non-Fermi liquid behavior in depleted Kondo lattices using strong-coupling and saddle-point methods.

Findings

Identification of inhomogeneous states with non-Fermi liquid properties

Rare weakly screened moments dominate susceptibility

Results applicable to specific heavy-fermion compounds

Abstract

We investigate the low-temperature behavior of Kondo lattices upon random depletion of the local $f$-moments, by using strong-coupling arguments and solving SU($N$) saddle-point equations on large lattices. For a large range of intermediate doping levels, between the coherent Fermi liquid of the dense lattice and the single-impurity Fermi liquid of the dilute limit, we find strongly inhomogeneous states that exhibit distinct non-Fermi liquid characteristics. In particular, the interplay of dopant disorder and strong interactions leads to rare weakly screened moments which dominate the bulk susceptibility. Our results are relevant to compounds like Ce_{x}La_{1-x}CoIn_5 and Ce_{x}La_{1-x}Pb_3