Emergent Kondo behavior from gauge fluctuations in spin liquids

TL;DR

This paper uncovers a novel non-magnetic Kondo effect driven by gauge fluctuations in spin liquids, revealing unique thermal and pseudospin behaviors that could serve as indicators of quantum spin liquids.

Contribution

It introduces a new type of Kondo behavior arising from gauge fluctuations, expanding understanding of many-body effects in strongly-correlated quantum spin liquids.

Findings

Gauge fluctuations mediate pseudospin exchange interactions.

Kondo phenomena show non-monotonous thermal conductivity dependence.

Features serve as indicators for quantum spin liquids.

Abstract

Kondo effect is a prominent quantum phenomenon describing the many-body screening of a local magnetic impurity. Here, we reveal a new type of non-magnetic Kondo behavior generated by gauge fluctuations in strongly-correlated baths. We show that a non-magnetic bond defect not only introduces the potential scattering but also locally enhances the gauge fluctuations. The local gauge fluctuations further mediate a pseudospin exchange interaction that produces an asymmetric Kondo fixed point in low-energy. The gauge-fluctuation-induced Kondo phenomena do not exhibit the characteristic resistivity behavior of conventional Kondo effect, but display a non-monotonous temperature dependence of thermal conductivity as well as an anisotropic pseudospin correlation. Moreover, with its origin from gauge fluctuations, the Kondo features can be regarded as promising indicators for identifying quantum spin liquids. Our work advances fundamental knowledge of novel Kondo phenomena in strongly-correlated systems, which have no counterparts in thermal baths within the single-particle description.