Identification of Strongly Correlated Spin Liquid in Herbertsmithite

TL;DR

This paper investigates the properties of a quantum spin liquid in herbertsmithite, revealing strong correlations, spin-charge separation, and behaviors akin to heavy fermion metals, supported by theoretical calculations matching experimental data.

Contribution

It provides a detailed theoretical analysis of the thermodynamic and relaxation properties of QSL in herbertsmithite, highlighting its formation as a strongly correlated Fermi system near a quantum phase transition.

Findings

Agreement with experimental thermodynamic data

Detection of spin-charge separation in QSL

Prediction of unique thermal resistivity behavior under magnetic fields

Abstract

Exotic quantum spin liquid (QSL) is formed with such hypothetic particles as fermionic spinons carrying spin 1/2 and no charge. Here we calculate its thermodynamic and relaxation properties. Our calculations unveil the fundamental properties of QSL, forming strongly correlated Fermi system located at a fermion condensation quantum phase transition. These are in a good agreement with experimental data and allow us to detect the behavior of QSL as that observed in heavy fermion metals. We predict that the thermal resistivity of QSL under the application of magnetic fields at fixed temperature demonstrates a very specific behavior. The key features of our findings are the presence of spin-charge separation and QSL formed with itinerant heavy spinons in herbertsmithite.