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arXiv · 0801.1102

Multiferroicity due to nonstoichiometry in the chain cuprate LiVCuO_4

A. S. Moskvin·S. -L. Drechsler
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Abstract

The recently observed multiferroic behavior in the s=1/2 chain cuprate LiVCuO_4 (LiCuVO_4) with edge-shared CuO_4 plaquettes and helical spin ordering does not agree with the existing theories such as a spin-current scenario. We argue that the effect can be consistently explained, if the exchange-induced electric polarization on the out-of-chain Cu^2+ centers substituting for Li-ions in LiVCuO_4 is taken into account. These substituent centers are proved to be an effective probe of the spin incommensurability and the magnetic field effects.

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A. S. Moskvin, S. -L. Drechsler. 2008-01-07. Multiferroicity due to nonstoichiometry in the chain cuprate LiVCuO_4. https://doi.org/10.1209/0295-5075/81/57004

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