$\mathbb{Z}_2$ metallic spin liquid on a frustrated Kondo lattice

TL;DR

This paper proposes a theoretical framework for a $ ext{Z}_2$ metallic spin liquid on a frustrated Kondo lattice, featuring fractionalized excitations and a partially enlarged Fermi surface, advancing understanding of correlated metallic states.

Contribution

It constructs an effective $ ext{Z}_2$ gauge theory for metallic spin liquids on a triangular Kondo lattice, introducing a new fractionalized heavy fermion liquid state.

Findings

Identifies a $ ext{Z}_2$ metallic spin liquid with long-lived holon excitations.

Describes a partially enlarged electron Fermi surface.

Provides a general theoretical framework for metallic spin liquids in frustrated Kondo systems.

Abstract

Metallic spin liquid has been reported in several correlated metals, but a satisfactory theoretical description is not yet available. Here we propose a potential route to realize the metallic spin liquid and construct an effective $\mathbb{Z}_2$ gauge theory with charged fractionalized excitations on the triangular Kondo lattice. This leads to a $\mathbb{Z}_2$ metallic spin liquid featured with long-lived, heavy holon excitations of spin 0 and charge $+e$ and a partially enlarged electron Fermi surface. It differs from the weak-coupling FL$^*$ state proposed earlier and may be viewed as a fractionalized heavy fermion liquid. Our theory provides a general framework to describe the metallic spin liquid in frustrated Kondo lattice systems.