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arXiv · 0901.2237

Vesignieite BaCu3V2O8(OH)2 as a Candidate Spin-1/2 Kagome Antiferromagnet

Yoshihiko Okamoto·Hiroyuki Yoshida·Zenji Hiroi
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Abstract

A polycrystalline sample of vesignieite BaCu3V2O8(OH)2 comprising a nearly ideal kagome lattice composed of Cu2+ ions carrying spin 1/2 has been synthesized and studied by magnetization and heat capacity measurements. Magnetic susceptibility shows a neither long range order, a spin glass transition nor a spin gap down to 2 K, in spite of a moderately strong antiferromagnetic interaction of J/kB = 53 K between nearest-neighbor spins. A broad peak observed at a temperature corresponding to 0.4J in intrinsic magnetic susceptibility indicates a marked development of the short-range order. The ground state of vesignieite is probably a gapless spin liquid or is accompanied by a very small gap less than J/30.

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Yoshihiko Okamoto, Hiroyuki Yoshida, Zenji Hiroi. 2009-01-15. Vesignieite BaCu3V2O8(OH)2 as a Candidate Spin-1/2 Kagome Antiferromagnet. https://doi.org/10.1143/jpsj.78.033701

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