Vesignieite BaCu_3V_2O_8(OH)_2 as a Candidate Spin-1/2 Kagome Antiferromagnet(Condensed matter: electronic structure and electrical, magnetic, and optical properties) OKAMOTO Yoshihiko YOSHIDA Hiroyuki HIROI Zenji 社団法人日本物理学会 Journal of the Physical Society of Japan 00319015 78 3 "033701 1"-"033701-4" 2009-03-15 A polycrystalline sample of vesignieite BaCu_3V_2O_8(OH)_2 comprising a nearly ideal kagome lattice composed of Cu^<2+> 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 2K, in spite of a moderately strong antiferromagnetic interaction of J/k_B=53K 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. 2009-03-15 110007138891 AA00704814 10182669 ENG CJP NDL NII-ELS 2 18 Vesignieite BaCu_3V_2O_8(OH)_2 as a Candidate Spin-1/2 Kagome Antiferromagnet(Condensed matter: electronic structure and electrical, magnetic, and optical properties) OKAMOTO Yoshihiko YOSHIDA Hiroyuki HIROI Zenji The Physical Society of Japan (JPS) Journal of the Physical Society of Japan A polycrystalline sample of vesignieite BaCu_3V_2O_8(OH)_2 comprising a nearly ideal kagome lattice composed of Cu^<2+> 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 2K, in spite of a moderately strong antiferromagnetic interaction of J/k_B=53K 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. OKAMOTO Yoshihiko Institute for Solid State Physics, University of Tokyo YOSHIDA Hiroyuki Institute for Solid State Physics, University of Tokyo HIROI Zenji Institute for Solid State Physics, University of Tokyo