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arXiv · 0902.3028

Magnetization "Steps" on a Kagome Lattice in Volborthite

Hiroyuki Yoshida·Yoshihiko Okamoto·Takashi Tayama·Toshiro Sakakibara·Masashi Tokunaga·Akira Matsuo·Yasuo Narumi·Koichi Kindo·Makoto Yoshida·Masashi Takigawa·Zenji Hiroi
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Abstract

Magnetic properties of the spin-1/2 kagome-like compound volborthite are studied using a high-quality polycrystalline sample. It is evidenced from magnetization and specific heat measurements that the spins on the kagome lattice still fluctuate at low temperature, down to T = 60 mK that corresponds to 1/1500 of the nearest-neighbor antiferromagnetic interaction, exhibiting neither a conventional long-range order nor a spin gap. In contrast, 51V NMR experiments revealed a sharp peak at 1 K in relaxation rate, which indicates that a certain exotic order occurs. Surprisingly, we have observed three "steps" in magnetization as a function of magnetic field, suggesting that at least four liquid-like or other quantum states exist under magnetic fields.

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Hiroyuki Yoshida, Yoshihiko Okamoto, Takashi Tayama, Toshiro Sakakibara, Masashi Tokunaga, Akira Matsuo, Yasuo Narumi, Koichi Kindo, Makoto Yoshida, Masashi Takigawa, Zenji Hiroi. 2009-02-21. Magnetization "Steps" on a Kagome Lattice in Volborthite. https://doi.org/10.1143/jpsj.78.043704

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