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arXiv · 1203.6107

Kapellasite: a kagome quantum spin liquid

B. Fåk·E. Kermarrec·L. Messio·B. Bernu·C. Lhuillier·F. Bert·P. Mendels·B. Koteswararao·F. Bouquet·J. Ollivier·A. D. Hillier·A. Amato·R. H. Colman·A. S. Wills
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Abstract

Magnetic susceptibility, NMR, muSR, and inelastic neutron scattering measurements show that kapellasite, Cu3Zn(OH)6Cl2, a geometrically frustrated spin-1/2 kagome antiferromagnet polymorphous with the herbertsmithite mineral, is a gapless spin liquid with frustrated interactions showing unusual dynamic short-range correlations of non-coplanar cuboc2 type which persist down to 20 mK. The Hamiltonian is determined from a fit of a high-temperature series expansion to thermodynamical data. The experimental data are compared to theoretical calculations using the Schwinger-boson approach.

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B. Fåk, E. Kermarrec, L. Messio, B. Bernu, C. Lhuillier, F. Bert, P. Mendels, B. Koteswararao, F. Bouquet, J. Ollivier, A. D. Hillier, A. Amato, R. H. Colman, A. S. Wills. 2012-07-23. Kapellasite: a kagome quantum spin liquid. https://arxiv.org/abs/1203.6107

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