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arXiv · 1008.5226

Cupric chloride CuCl2 as an S=1/2 chain multiferroic

S. Seki·T. Kurumaji·S. Ishiwata·H. Matsui·H. Murakawa·Y. Tokunaga·Y. Kaneko·T. Hasegawa·Y. Tokura
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Abstract

Magnetoelectric properties were investigated for an S=1/2 chain antiferromagnet CuCl2, which turns out to be the first example of non-chalcogen based spiral-spin induced multiferroics. Upon the onset of helimagnetic order propagating along the b-axis under zero magnetic field (H), we found emergence of ferroelectric polarization along the c-axis. Application of H along the b-axis leads to spin-flop transition coupled with drastic suppression of ferroelectricity, and rotation of H around the b-axis induces the rotation of spin-spiral plane and associated polarization direction. These behaviors are explained well within the framework of the inverse Dzyaloshinskii-Moriya model, suggesting the robustness of this magnetoelectric coupling mechanism even under the strong quantum fluctuation.

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S. Seki, T. Kurumaji, S. Ishiwata, H. Matsui, H. Murakawa, Y. Tokunaga, Y. Kaneko, T. Hasegawa, Y. Tokura. 2010-08-31. Cupric chloride CuCl2 as an S=1/2 chain multiferroic. https://doi.org/10.1103/physrevb.82.064424

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