Advanced Materials: Nature of Strongly Correlated Quantum Spin Liquid in Sr₃CuNb₂O₉

Abstract

Quantum spin liquids of frustrated magnets are among the most attractive and basic systems in physics. Frustrated magnets exhibit exceptional properties as insulators and metals, making them advanced materials that represent materials for future technologies. Therefore, a reliable theory describing these materials is of great importance. The fermion condensation theory provides an analytical description of various frustrated quantum spin liquids capable of describing the thermodynamic and transport properties of magnets based on the idea of spinons, represented by chargeless fermions filling the Fermi sphere up to the Fermi momentum pF. We show that the low temperature thermodynamic of Sr₃CuNb₂O₉ in magnetic fields is defined by strongly correlated quantum spin liquid. Our calculations of its thermodynamic properties agree well with recent experimental facts and allow us to reveal their scaling behavior, which is very similar to that observed both in heavy-fermion metals and in frustrated magnets or insulators. We demonstrate for the first time that Sr₃CuNb₂O₉ belongs to the family of strongly correlated Fermi systems that form a new state of matter.

Keywords

Quantum phase transitions / Flat bands / Quantum spin liquid / Thermodynamic properties / Scaling behavior / Universal properties / Heavy fermion metals

Acknowledgments

We thank M. Kumar and M. Majumder and all the authors of Ref. [16] for providing the experimental data and the corresponding files.

Author Contributions

V.R.S. and A.Z.M. designed the project and directed it with the help of S.A.A. and Y.S.L.; V.R.S. and A.Z.M. wrote the manuscript and all authors commented on it. The manuscript reflects the contributions of all authors. All authors have read and agreed to the published version of the manuscript.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availibility Statement

The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.

Funding

This work was supported by Division of Chemical Sciences, Office of Basic Energy Sciences, Office of Energy Research, AFOSR.

Declaration of Competing Interest

The authors declare no conflicts of interest.

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