Averievite: a copper oxide kagome antiferromagnet

TL;DR

Averievite is a copper oxide kagome antiferromagnet with potential for hosting quantum spin liquids and novel electronic states, demonstrated through synthesis, experimental measurements, and ab initio calculations.

Contribution

This study synthesizes averievite and explores its magnetic and electronic properties, proposing substitutions that could realize spin liquid states and Dirac electronic structures.

Findings

Long-range magnetic order at 24 K due to interlayer coupling

Substitution with zinc suppresses magnetic order, indicating spin liquid potential

Predicted Dirac crossings in Ti-doped variants

Abstract

Averievite, Cu$_5$V$_2$O$_{10}$(CsCl), is an oxide mineral composed of Cu$^{2+}$ kagome layers sandwiched by Cu$^{2+}$-V$^{5+}$ honeycomb layers. We have synthesized this oxide and investigated its properties from ab initio calculations along with susceptibility and specific heat measurements. The data indicate a Curie-Weiss temperature of 185 K as well as long-range magnetic order at 24 K due to the significant interlayer coupling from the honeycomb copper ions. This order is suppressed by substituting these coppers by isoelectronic zinc, suggesting that Zn-substituted averievite is a promising spin liquid candidate. A further proposed substitution that replaces V$^{5+}$ by Ti$^{4+}$ not only dopes the material, but is predicted to give rise to a two-dimensional electronic structure featuring Dirac crossings. As such, averievite is an attractive platform for S=1/2 kagome physics with the potential for realizing novel electronic states.