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arXiv · 2205.02709

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

Jiangfan Wang·Yi-feng Yang
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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.

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Jiangfan Wang, Yi-feng Yang. 2022-05-05. $\mathbb{Z}_2$ metallic spin liquid on a frustrated Kondo lattice. https://doi.org/10.1103/physrevb.106.115135

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