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Spin-1/2 Kagome Like Lattice in Volborthite Cu3V2O7(OH)2-H2O

Z. Hiroi·M. Hanawa·N. Kobayashi·M. Nohara·H. Takagi·Y. Kato·M. Takigawa
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Abstract

A novel cuprate Volborthite, Cu3V2O7(OH)2-2H2O, containing an S-1/2 (Cu 2+ spin) kagome-like lattice is studied by magnetic susceptibility, specific heat, and 51 V NMR measurements. Signs for neither long-range order nor spin-gapped singlet ground states are detected down to 1.8 K, in spite of large antiferromagnetic couplings of ~100 K between Cu spins forming a two-dimensional kagome-like network. It is suggested that Volborthite represents a system close to a quantum critical point between classical long-range ordered and quantum disordered phases.

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Z. Hiroi, M. Hanawa, N. Kobayashi, M. Nohara, H. Takagi, Y. Kato, M. Takigawa. 2001-11-10. Spin-1/2 Kagome Like Lattice in Volborthite Cu3V2O7(OH)2-H2O. https://doi.org/10.1143/jpsj.70.3377

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